Up the tower : the complete guide to tower construction 9780615285146, 0615285147

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Up THE TOWER THE COMPLETE GUIDE

To TOWER CONSTRUCTION by

STEVE MORRIS K7LXC

w) .

CHAMPION

:r~

RADIO

I PRODUCTS

Up

THE TOWER

THE COMPLETE GUIDE To TOWER CONSTRUCTION

Text and photographs copyright © 2009 by Steve Morris

Published by

CHAMPION RADIO PRODUCTS

16541 Redmond Way #281 -C, Redmond, WA 98052 ISBN 978-0-615-28514 -6 All rights reserved. Permission is granted to copy or reprint portions for any non-commercial use, except th ey may not be posted online without permIssIon. Printed and bound in the United States of America.

CONTENTS I NT RO DUCTI O N FC)RE\\rORD

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20

D o YOU REALLY NEED A TOWER? A NT EN NA SUPPO RTS PI .l\ NNI NG L AND USE REG ULATIO N OF A~ IATE UR RAD IO TOW ERS OTHE R REG ULATORY CO NCE RNS NE IGHBORS HIR E SOMEON E O R DO IT YOURSELF? D O CUMENTATI O N CO LLECTI NG THE HARDWARE CO RROSIO N FO UNDATIO NS AN D GUY ANC HO RS S AFETY AND SAFETY EQ UIPMENT T OWER CUM BER AND G ROUND CRE\'(' T O OL BOX C ARABIN ERS AND SLIN GS R OPES , KNOTS AND ROP E MANAGEME NT G UY WIRES T OWER ERECT ION IvI ASTS C OAXIAL CABLE

5 6 9 12 25 29 48 54 56 58 60 64 69 81 89 94 101 107 114 123 131 137

[continued on next p age]

CONTENTS [continued fr Olll precedillg page]

21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36

W EATHERPROOFI NG R OTATO RS I NSTALLING B EA~I S GRO UNDI NG B UILDI NG A SIN G LE T OWER STAT ION B E KI ND TO YOUR T REES TRE E INSTALLATI O NS THE TE N YEAR PLAN R EFURBISHING A TOWER Mt\lNTENANCE AND ANNUA L INSPECTIO N W HEN SOMET HING FAILS INSURANCE A NTENNAS T OWER REMOVAL WORKI NG ON A CRANK-U P A FEW' FINAL TI PS I N DE X

146 150 157 164 187 189 198 206 210 213 217 221 227 232 235 238 243

INTRODUCTION by Bob Locher, W9 KN I

Steve Morris is a master o f tower wo rk. Not o nly has he done it all " Up th e Tower" but he trul y brings a broad-based understanding o f towers to thi s wo rk. Steve has had an accomplish ed caree r as a ham, bo th as a ho bby and in the bu siness o f amateur rad io, and years of experience in erecting, climbing and installing towers, ro tators and antennas. This book presents th e knowledge he has gained . Steve's years of acting as mod erator o f the "Tower Talk" internet reflector have further helped him prepare this bo ok , helping him to unde rstand wha t subjects confuse newc omers. Steve wo uld be the first to tell you th at a success ful tower proj ect is well over half finished be fo re the conc rete is ever po ured - planning and design lead to successful execution. Steve's bo ok tells you how to do th e planning, th e design - and the executio n! All with safety and engineering as paramount obj ectives. If you are plannin g any tower installation, this book will certainly be your guide and companio n and the best investme nt you can make. There has never been a compre hensive book for amateur radio towers, bu t it was worth the wait - now we have Steve's masterpiec e. de Bob Locher, W9KNI

FOREWORD Although I was first licen sed in 1960, being in the serv ice, college and havin g a new family put me off the air for almost ten years. Not until 1978, with th e assistance of childhood buddyJim Hadlock, K7 WA, did I get back on the air with som e simple wire an tennas. "Wire antennas world " was the entry in my logbook after making my first few contacts. My enthusiasm was increasing by leap s and bounds and befo re I kn ew it, I had purchased a used to wer and a used cubical quad ante nna. Since I had never before attempted anyth ing like thi s, I tried to find o ut what to do . I had m ore que stions than an swer s but armed with only the help of the R OHN catalog, J im and a co uple of o the rs, we go t it up. Boy, now I was cruising th e HF band s and having fun ! A year or two later, a big winds torm came through and bent ove r th e installation. After repairing everything and adding a set of guys, I was back in bu sine ss. Lo o king ba ck, I see that my lessons were learned th e hard way and fortunately without any damage to life or prop erty; I was lucky. I did more and more tower and antenna wo rk and I still had to learn ever ything the hard way. I even progre ssed to the po int where I started up my own tower serv ices contracting company. Starting out with hams, I soon got more and

F OR E WORD

7

mo re involved in cellular, communications and bro adca st work and 1 learned even more from each of those projects. In 1991 I started writing a column on tower construction for th e National ContestJOllrnalbecause I wanted to share my experiences and lessons with other hams, and hopefully help them avoid learning th e hard lessons them selves. T hat is wh y I wrote this book; I don't want you to learn everything the hard way by doing things you sho uldn 't be do ing and having failures that coul d be endangering your life and property and co uld have been pr evented . I want you to have all o f the answers at you r fingertips in this book; I want you to be able to install a tower and antenna system safely and reliab ly. T his wa sn't an adventure that I took on by myself; I would like to thank these folks for their co ntri butions over the years: Bre tt Graham, KB7G jVS6BGjVR2BG, who was my first tower partner on several tower adventures; Rush Drake, W7RM (SK, Silent Key), whose vision and ingenuity (no t to mention hea vy duty ginpole and winch!) helped me more than once; Tom Taormina, KSRC, my first editor at the NationalContestJournal, who encouraged my column and helped me improve my writing; Pat Meeks, KS7L, who crea ted much of the art and enhanced most o f the remaind er; to my original editor and publisher, J ohn Polloc k, K7MCX, for his encouragement and th e long hours spent in whipping this bo ok into initial shape; and of course Bob Locher, W9KNI, who has encouraged, cajoled and mentored m e o n this project. In addition, thanks to the pe ople who read and provided input into the form and content of the book, incl uding Rob Brownstein, K6RB, Jim D uffy, W6 EU, Bob E pstein, K 8IA and Fr ank D onovan, W3LPL. Thank you!. T his book has been writte n for those wh o wish to safely bu ild their own tower and ante nna system. It is not intended to be used fo r co mme rcial purpo ses. To have bo th a safe and reliable pro ject, th e autho r reco mme nds th at yo u adhere to the variou s safety guidelines o utlined in this book. Your safety is important and should no t be jeop ardi zed . The reader is ultimately responsible for his ow n safety, and fo r all decisions he makes co ncern ing his safety. T he reade r must, himself, verify the accuracy of informa tion provid ed, and the text constituting ge neral informatio n int ended to make th e tower climb er aware of the dan gers. The book provides no particular ad vice, for

8

Up

THE TOWE R

any particular, localized, situation that I have no t fully analyzed. In the United States , worker safety is regulated by the O ccupational Safety and Health Agency (O SHA). As a private individual, you (as well as yo ur friends wh o assist you in your tower building proj ect) are exempt from O SHA coverage. Although you are not required to follow the OSHA rules and regulations, for safety purposes my advice is that you apply them in yo ur project. Becau se safety is so very important, O SHA rules and regulations are discussed fro m time to time through out this book. However, it mu st be clearly understood th at this bo ok is a " do it yo urs elf " guide to the private construction of amateur radio o r personal radio towers and /or antenna systems, and is not int ended to be an OSHA co mp liant textbook. Some of the equipment and tec hni ques described in thi s book are not OSHA compliant but are presente d because the author has found them to be safe and valuable for private radio tower co nstr uction pur poses. Altho ugh the auth or and pub lishe r o f thi s boo k have used thei r best efforts in preparing the book and the m aterial contained in it, they make no warranty of an y kind, expressed or imp lied, wit h regard to the material contained in this book or its application in the construction of any tower and antenna system s. T he author and publisher shall no t be liable in th e event o f incidental o r consequential damages in co nnection with, or arising out of, the applicatio n o f an y o f the material or contents of thi s book. U sers of this book sho uld consult the provisions governing limitation of liability and disclaimer of warr anti es in co nnection with equipme n t, tools and supplies purcha sed and utilized in th e construction of any tower and / or antenna system. Regardless of wh o does the work, your careful atte ntio n to the safety guidelines outlined in this bo ok should provide you with a completed project that is safe, succes sful and reliable.

1 Do

YOU REALLY NEED A TOWER?

Any type of radio comm unications requires an antenna. \Vheth er it's a microwave dish, a shortwave dipole o r beam, or a half-mile wire strung across a canyon for sub mari ne traffic, nothin g ha ppens witho ut it. In o rde r to radiate effectively, th ese antennas need to be mo unted up in the air, on a tower or stru cture of so me sort. Those of you who have tried , with varying levels of succ ess, to op erate out o f an apartme nt or co ndo know how frustrating and limiting that situation can be. O n the other hand, those o f you who have had the good fortu ne to ow n or operate from a good station with tall towers and effect ive anten nas know how th rilling that expe rience is. This book is writte n for anyo ne who has ever co ntemplated installing an outdo or antenna system , ma y be planning one or who already ha s some experience bu t wants to know more abo ut proper tower system constru ction and tec hniques.

The negatives O ne o f the biggest ch allen ge s fo r man y people is the co st. Even a used tow er and antenna system can mean an investment of a

10

Up THE TOWER

th ou sand dollars or more. Hire someone to ins tall it for you and the cost goes up. Ano ther problem is th at it may be difficult to get the nec essary permits and permi ssions to buil d your dream an tenna system. H earings with building departmen t board s and civil law suits are no longer uncommon. N eighbors can be a big negative if th ey are opposed to your installation. Just one complaining neighbor can be a real irritant, not o nly to you but also to the local building depart ment. T his can be a case where th e " squeaky wh eel" gets grease d, usually to your disadvan tage. W hile som e proposed towers wind up being ch allenged du e to perc eived radiatio n emissio n problem s, man y of th e confrontatio ns are bec au se o f aesthetic reasons. Even if a tower doesn't bloc k their view, a neighbor may feel that it is an unnecessary eyeso re. Of course for the ow ne r it' s a case of beauty being " in th e eye of th e beholder." Some people use the argument that a tower will lower th e resa le values in a neighborhood. In my opinion, thi s is a pretty weak argument and more of a smokescreen. Not only hav e I never seen an y professional survey s that reflect that negative view but also my exp erience in selling my ow n home was th at my first two offers included the tower!

The positives The biggest posiu ve for in st alling an y typ e of o utd o or antenna syste m is th at you'll be ab le to tran smi t and re ce ive much mo re effe ctively. H igh antennas almost always wo rk bet ter tha n low anten nas, and very rar ely will yo u ge t an anten na " too high. " Whe n it comes to antenna and tower p rojects, the " sky is the limit. " A properly installed tower and antenna system will also rewa rd yo u with years of reliable

Photo 1:Alovely station toaspire to. Your dream station?

I-Do

YOU REALLY NEED A TO\\ 'ER?

11

performanc e. In case o f a public eme rge ncy, your ant enna system may well be the key to saving lives and property. The ultimate reward, though , is that a decent tower and antenna system will resu lt in your having much m ore enjoym ent from your radio statio n and your hobby.

2 ANTENNA SUPPORTS O nce yo u've decid ed th at yo u wa nt to put up an antenna, yo u still have m any cho ices to make. T he first is probably which kind o f an antenna you want to install. T he second cho ice is what kind o f support to use.

Trees T he first amateur radio antennas were simple wires and their ow ne rs typically stru ng the m in whatever trees tha t were handy. We'll loo k more dosely at trees in Cha pters 26 and 27.

Wooden utility poles Wooden poles are no t nearly as popular as th ey we re in the pa st . There was a time whe n reasonably priced steel tow er s with amateur compatible hardware were not readily available. With utility po les springing up as electricity and telepho nes became almos t unive rsal in America, amateurs devised innovati ve ways in which to use these antenna sup ports . You may still be tempted to put up o ne of

2- AN TEN N A SUPPO RTS

13

the se wooden po les for any number of reasons. Usa ble po les can be obtained new in just abo ut an y part of the count ry and used o nes can so me times be found in the p ole yard of your local utility or telephone co mp an y. As long as it is sound and the base is treated with a preservative , all you ne ed to do is find some one to pu t it up for you. A pole-setting rig can be hired th at will drill th e ho le and set th e pole in o ne visit. If you have a neighbor or buddy who 's a lin em an, th en you migh t have so meone who can install it and wo rk o n it for you. The big problem is tha t there is no hardware available fo r ama teur ant enna use, so you 'll have to fabricate your ow n rotator mounting and antenna hardware. You can lag screw a pip e to th e side o f th e pole and use a mast-m ounted rotator , or yo u can get mor e exo tic with a rotator mounting cage o f some sor t. You'll have to improvise much o f this as you go along. T he lack of hardware is a disadvantage to pole use. They're also harder to clim b and work on th an a steel tower; you may need linem an's climbing spurs at some point. In addition , they're dirty and can give you nasty splinte rs.

Other wooden supports During the 1950's and 60's, ham magazine s frequ entl y co ntained arti cles with a construction project for a wooden tower or mast of some sort. T hese fell (no pu n int ended) into disfavor because th ey really couldn't p ro vide a long term, safe, reliab le antenna suppo rt. These days, with a var iety of modestly priced steel and aluminum towers available, yo u shouldn' t even con sider b uilding on e of the se.

Push-up masts With length s from 20 to 50- feet, pu sh-up ma sts used to. be very popular for TV ante nnas and could also be used for sma ll ham ante nnas. With th e advent of satellite Tv, the pu sh-up ma st has fallen out of favor. T hey used to be available fro m Radio Shack bu t they don 't sto ck them anymore. Rohn makes them bu t no wada ys th ey have to be shipped fro m somewhere and man y times th e shipping cost exceeds the cost of th e mast so they're no t really feasible anymo re. The materi al used for the se pu sh -up s is relatively heavy but not very strong. Sinc e each ten -foot section needs to be guyed, a for ty-foot push-up will have fou r sets of guy wire s. It's a tricky propo-

14

Up THE

T OIFE R

sitio n to put one o f th ese up since all of the guy wires mu st be pr einstalled, and yo u have to pu sh it up from the bottom while trying to keep it from tipping ove r. If you o nly have a small VH F/UHF installation to put up, if you've go t someone who know s how to safely install o ne o f these and if you don't mind no t being able to serv ice yo ur installation, this can be an inexpensive way to go .

Roof mounte d supports A very sim ple way to get sta rted is to use a roof-mounted tower fo r your antenna suppo rt. T hese come in different configurations , from ligh t-du ty tripods de sign ed fo r TV antenna mounting to a real live 4-legge d mini-tower that will take a rotator and mast. The key is se c uring t he tower wit ho ut damaging th e ro of; and not falling off while doing it! Fo r safety's sake, always use a fall-arrest syste m of so me sort w hi le worki ng o n a roof. A simple meth od is to tie a large loop o r rope around a chimney; Photo 1:Agood wayto mount anantenna. AA20W's th en tie yo urs elf in to roof-mountedtower.AA20W photo. that with a lo ng lanyard or pie ce of rope attached to yo ur fall-arrest harn ess. Securing the tower to the roof isn't difficult; fo r smaller towers just be certain the lag screws are attached directly int o roo f tru sses, then use a roo f patching tar to seal the holes against water dam age. For larger towers, use all-thread or lo ng lag bolts th rou gh the roo f and into a backing plate such as a long 2x4 or 2x6 th at ru ns between 3 to 4 tru sses; then attach the nu ts and lockwashers from inside the attic. Two importan t things to keep in mind. First, any time yo u penet rate a ro of m embran e it ca n leak. U se ro o fin g tar or p atch in g compo un d liberally, and check o ut th e in stallatio n from in side the attic occasionally to in sur e that no wa te r is leaking into

2 - ANT EN N A SUPPORTS

15

the house. Second, wh ile roof-mounted towers are fair ly benign to mo st roofs, a moderate sized tower usi ng roof guy anchors can actually loosen a roof over tim e. Back and forth win d forces o n twe nty or th irty feet o f R OH N 25G can cau se pe rmane n t roof di slo catio n problems. A thoug htful and carefully o ver-e ng ineered job will minimize th is type of problem . If you have a sm all city lot , you may consider using a chimney or oth er building feature. This is not encouraged since chimneys (along with other hou se app urtena nces) are not good from a structural standpoint and man y are in poor condition to begin with. Chim neys are heavy but have no structural strength so the y are not good places for mo unting HF yagis. T hey can be used for VHF/ UHF verticals or yagis th ough. You can dr ap e wire an tennas around the ho use and yard; the y'll probably work just fin e. This may b e a cha llenge, and exploiting yo ur limitations ma y w ell make yo u a better and m ore re sourceful operator. If you can use an y existing appurtenances such as a vent pipe, m ast o r roof structure to attach an end of a wire antenna, it may mak e thin gs fairly simple. The maj or problem wit h any roof-mounted installation is avoiding pen etrating the ro o f membrane at all cos ts. Your biggest ob sta cle may well be convincing yo ur land lord or building m ana ger or spo use that yo ur installation will have no impact o n the integrity of their roof. If yo u can't attach to anything already on the roof, yo u sti ll h ave one good option ; using so me sort o f gravity mount. A gr avit y mount is held down by g ravity, usually Photo 2: Non-roof penetrating gravity mount. by placing concrete blocks Easily adaptable toham antenna applications.

16

Up m

E T OIf7ER

o n th e mount itself. Roo ftop satellite dishes are co m mo nly installed with this type o f device. Co mme rcial mounts are available th at will hold a sate llite dish, are fully galvanized and have a typica l pric e o f aro und $250. These migh t b e overkill fo r am ateur use because a ten foot dish has ov er fo rty square feet o f wind loading whe re an allband H F vertical typically has less than four, but the y would be very reliab le. The parts consist of a tray to hold the cement blocks, th e mast for antenna mounting and bracing between th e tray and th e mast . If yo u make one o f the se from aluminum angle, it should be quick and simple to fabricate. Be sur e to use stainless ste el hard ware. O bviously yo u need so me flat ro of area to set this o n.

Tower basics Tower sectio ns consist of legs and diagonal and ho rizontal braces. They can eith er be round members such as ROHN 25G o r angled m embers that use 90 or 60 degr ee angles for legs, diagonals or ho rizontals. Round membered towers such as ROHN 25G, etc. are the m ost common for ama teur towers. T he tower face is th at out ward facing area between the legs th at has the braces. TV antenna towers There are man y towers th at were spe cifically designed and installed for TV antennas. T hese tend to be at the low end of suitability for ama teur use. They were no t design ed for the larger loads of ham antennas, but are used by tho usands o f amateurs nonetheless. T hese TV ant enna towers are generally forty -feet or so in heigh t and are installed witho ut guy wires. The most common are th e ROHNSPAULDING (NOW ROHN) AX OR BX series-typ es and a tubular-legged type, similar to ROHN 25G. T he BX- typ e is made fro m stamped steel, and has X bracing. T he X's are not co nnecte d to each o ther and the commo n failure po int is between th e braces. Also, th e rotator and top plates are made fro m sheet metal and can crack from wind-induced metal fatigue For small tribanders and VHF arr ays th ey are just fine, but be careful of overload ing the ones using the sm aller sections. Rohn caution s that these towe rs sho uld be limited to ante nnas with boom length s of less th an 10 feet since they hav e minimal torsion resistance . T here are several T V-type tower varieties including th e Rohn

2-

A N T EN N A SUPPO RT S

17

6G and 20G. O ther types typically have tubular legs but only have ho rizontal bracing and lack diago nal braces. T hese are o kay for sma ll antennas but engineering caution should be used in all installations. The Rohn 6G is in this category. Rohn 20G on th e other hand doe s have th e Z -bracing and is the sam e size as 25G and in fact the accessories are compatible, bu t there are only 7 horizontals instead of the 8 hori zontals o f 25G and thus does not have the torsi on resistance of 25G. Rohn cautions that 20G is not suitable for commercial, ham, CB or gu yed in stallatio ns.

Self-supporting towers ROHN used to produce th e popular BX series of towers consisting o f models BX (standard), HBX (heavy-duty) and HDBX (extra-heavy -duty). T his tower series was origina lly designed for TV antenna use and ha s its limitations for ama teur applications. There are eight tap ered BX sectio ns that are used in all configurations. The BX 8 is the largest section, and is used as the bottom section of the HDBX series. The BXt section is the sma llest section and is the top section of the BX series. Although the HBX series is rated at ten-squ are feet of antenna load and the HDBX is rated at eighteen -square feet, the win d pressure is only 20 PSF, or 70 MPH, and the ma ximum boom length "should be limited to ten -feet." The maximum height of an HBX is 56 feet and the maximum height for an HDBX is 48 feet . If you wa nt to go higher than 60 feet with a self-supporting tower, a crank-up tower, Tr ylon , AN Wireless or ROHN SSV may be your choice s. A self-suppo rting commercial tower such as th e Trylon or SS V will not only be pric e competitive against a similar sized cran kup but also will be rated and certified at higher wind speeds. H ere are a co up le of more points about the BX series. They are riveted together, no t welded, and they are not hot-dipp ed galvanize d after assembly as are ROHN 25G or 45G. The integrity o f th e galvanizing does not last as lo ng as th e hot-dipped variety. Because th e braces are installed at th e X angle and are not flat, your feet tak e a real beating whe n you have to work on o ne of these towers. And whe n you get up around the rotator , so me times you can't get your feet to fit in anyw here. D on't let me discourage you from putting one o f the se up . In th eir favor, th ey are relatively in exp en sive, are common almost ev-

18

Up TH E

T OW"ER

erywhere and can be pick ed up used for as little as $100. Just be aware of their limitations. ROHN BX used to be called ' 'SP/l UW INC'' and th e same design is currentl y manufactured in Canada as ''DEUlI'' tower s. U NIVERSAL M ANu rACTURI NG (www.U n iver saIT owe rs .co m) produces a line o f self-s upporting aluminum towers th at are touted as being lightweight, ru st free and eas y to as semble. T hey are, ind eed , all of th o se th ings. T hey weigh ap p rox ima te ly half as much as their ROH N BX counterparts, their aluminum parts wo n't ru st and, being lighter, th ey go together easily. The price you pay is for the higher co st o f th e alumin um materials; th at p rice can be tw o to four times th at o f a comparable steel tower . T he re are o nly two sligh t drawbacks to using an aluminum self- supp orting tower. O ne is that the to wer will move around quite a bit when yo u are up wo rkin g on it. The other is a p o ten tial for leg ho le elongation over time as the tower rocks in th e wi nd. The aluminum leg will b e working against the stee l nut and bo lt, and in severe cases can elongate the bo lt ho le, potentially to failur e. Another aluminu m tower ma nufacturer is H eights Tower Systems (www.heigh tstowers.co m) who also makes crank-ups in additio n to th eir line of free standing tower s. T he crank-up ve rsio n is also available in a tra iler-mounted configuration. Their base size requirem en ts are slightly larger th an for ROHN BX , using a five-foot square hole six-feet deep and six yards o f concrete. Some additio nal accessory item s are available. One big caution is that aluminum towe r sections sho uld never be placed directly in co ncrete. The corrosive effects of concrete (it contains lye) will destro y the aluminum tower sectio ns where galvani zed steel sections do not suffer the same fate .

Rohn SSV Rohn SSVis a professional, relatively heavy-du ty tower line that has been traditionally used by commercia l commun ications and broadcast users. Freestand ing up to 320 feet, this is a m ore challenging erec tio n job, since the sections can weigh hu ndreds of po unds and are twen ty-feet long instead o f ham-stand ard ten-foot sectio ns. T he easiest way to erect this tower is to assem ble all of the sections while they are laying on th e ground, then to use a cran e to pick up each

2 - AN T EN N A SUPPORTS

19

sectio n and lower it int o plac e. Figure abo ut a half-day to assem ble each sectio n, and four ho urs of crane time to stack o ne hu nd red feet of it in th e air.

Trylon Titan towers F airly new to h am Try lo n a p p lic a t io ns , m a kes a n ice s e lf- s u p p orter th at'll go up to 96feet. At that heigh t it's a relat ive ly ligh t-du ty tower (rate d for 15 square feet at 70 MPH) but the capacity increases as you decr ease the he ight m ore o r less. What h ap p en s is that the re are 12 sect io ns with th e bi g g e st b e in g 4 6 " acro ss th e b ottom fac e and th e sm allest b eing 9" ac ross th e t op. As yo u a d d o r remo ve t op o r b ot t om s e c t io n s, t he Photo 3:ATrylon Titan self-supporting towerin hei ght and capacity varies. Bandon, OR. The proud owners are W7WVF and I t's po ssibl e to get a mod - N7YYG. erate hei ght tower w it h lo ts o f capacit y as the to p se ctio n gets larger. For examp le th e T500-72 is the m o st p o pu lar ham con figuration and will h andl e 45 sq uare feet at 70 MP H for a m oderate am o un t o f m oney. T h er e are top and ro tator p lates ava ilable as well. Trylon also makes a Sup er T itan that is mor e similar to Rohn SSV in its spe cs and pric e.

AN Wireless AN Wireless mak es a line of very robust self-supportin g towers. Since a tower cost is a function of ho w much steel is in it, they also have ro b ust price tags. Check wwwanwire less.co m for m ore info.

20

Up "[HE

T Olf/ l i R

House-bracketed towers Rohn 25G, 45G and 55G can all be installed using a hou sebracket attached to the building as part of the st ru cture. C urrent Ro hn spe cs allow the to p of th e tower to be above th e ho use- Rgure 1:Rohn housebracket bracke t 14 feet o r mo re dep ending o n windspeed conditions and antenna load . Co nsult a Rohn catalog or the Rohn website (www.ro hnnet.co m) for mor e details. Freestanding 25G, 45G and 55G towers are a sub-set o f hou sebracketed towers since you're again using a guyed tower in a nonguyed scenario. Again, chec k th e Rohn specs to see what th e limitatio ns are. Crank-up towers Crank-up towers have th eir advocates and they can be an elegant solu tio n to many tower installation challenges. Basically,a crankup tower is made up of two or more tower sections that nest inside each other and are pu lled up progressively with a system of cables, pu lleys and a winc h. These winch crank- up systems are either electri cally powered or are manu ally ope rated. They are genera lly self-su pporting and require a large base foun da tio n similar to th ose disc usse d above. T he purpose, by the way, fo r a large foundation fo r a selfsupporting tower is so tha t th e center of gravity o f th e tower is below the ground level. O therwise a big wind and big wind pressure co uld cause it to tip over. Many amateurs feel a crank -up increases th e safety o f the ir installation by being able to crank it down in case o f a windstorm. Well, yes and no . If yo u keep it cranked down except whe n you're actually using it, you can minimize an y windstorm effect s. Un fort unately if your tower is crank ed up and a wind storm comes along, you probably won 't be able to crank it down bec aus e o f the wind pr essure on th e sections; th at is o f course, if you're home in th e first

2 - ANTEN NA SUPPORTS

21

place. Some crank-ups have positive pu ll-down which would allow you to lower th e tower in spite of having wind force o n it. Also, going o utside at night in th e middle of a storm to crank it down may be a deterrent in its elf. A motorized system wit h the up-down switch in th e shack is an elegant, alth ough expe nsive, alte rn ative. When raising or lowering a crank-up tower, you AL\XfAYS ne ed to be looking at th e tower as it's mo ving. It is no t uncommon for som ething to snag if yo u're not looking at it and able to respond immediately, you can have a serio us breakag e - usually in the cabl es. If you 're using a hamshack rem ote control and not paying attention, you're askin g for trouble. Alo ng with being able to lower the antenna system , man y crank ups have the ability fo r the whole tow er and ant enn a system to be lowered hori zontally or tilted -over to facilitate antenna work. Again you'r e adding ano the r layer o f mechanical complexity and cost th at ma yor ma y no t be wo rth it. T he forces that are generated by tilting a tow er over and lifting it back up again are tremendous and are not to be taken lightly. U nless yo u h ave goo d en gineering and fabricati on experience, don't try to fabricate the tilt- o ver h ardware yo urs el f. The manufactur er spent a lo t of mone y to de sign and fabricate a safe tilt-over fixture and that is the one you sho uld use. Don't try to rein vent the wheel! T he sma ller a n d less expensive crank-up s can either be tubular in de sign o r use m ore conventio na l la t tic ed sections. The m edium and Photo 4:An impressively loaded and effective large con figur at io n s are USTower crank-up system owned by K6KR.

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Up THE

T OWE R

fo r th e m o st part diag onally b ra ce d towe rs. D o not guy a cran k-up tower if the manufacturer does not speci fy it. The adde d ten sion of the guy wires could increase the fo rce o n the tower hoistin g cabl e eno ugh to cau se it to fail.

The LXC Prime D irective T hroug hout this bo o k I'm go ing to refer to th e LXC Prim e Directive repeated ly. Simply put, it states th at yo u sho uld always "DO w ha t th e m anufacturer says." Don't rein vent the w heel or conjure up so mething yo urself. P rofessional eng ineers and designers have come up wit h th e d esign s and specs an d th ere is very littl e ch ance th at an amateur co uld do the same cre di ble jo b. In all cases , th e auto matic default fo r any tower sys te m question is the m anufacturer's spe cifica tio ns . T here is a corollary to the Prime D irecti ve and it is " DON'T do what the m an ufacturer do esn 't tell yo u." In o ther words, if the manufacturer doesn' t say to do something spe cifically, don't do it. I was personally involved with an antenna installation where whe n th e antenna was finish ed , th e owner sp rayed th e who le thing with acrylic spray paint. D id the manufacturer say to do th at? No, th ey didn't . \xrhat hap pen ed was that the paint reacted wit h the lexan element br ackets and in a couple o f days they all cracke d and had to be rep laced .

Guyed towers The accepted standard fo r am ateur tower installatio ns is guyed towers in genera l, an d R OHN 25C, 45C and 55C in particular. ROH N products are stro ng, reliable, relatively easy to erect and have a wide array of ama teur compatible accessories. With a face width o f twelve inches and a ten-foot section weight of forty pounds, a R O J'JN ginpole and a ground crew is the recomme nded way to install R O HN 25C. A prac tical heigh t limit o f 190 feet at 90 MP H wind spee d gives you 7.8 square feet of antenna load capacity. A l Ou-foot in stallation yields 9.1 square feet of antenna cap acit y, eno ugh fo r a small stack of monoband yagis or a high perform ance tribander. An experien ced crew can erect up to a h undr ed feet a day o f this popular tower. R O H N 45C is 18 inc hes across th e face an d a ten-foot section

2-

A N T EN N A SUPPORTS

23

weighs 70 po unds . T his ro bust tow er is rate d up to 240 feet in 90 MPH wind s, w ith a windload rating of 16.3 square feet. At a height of 100 feet the wind loading is 21.5 square feet, after you've adde d bac k in th e 8.0 square feet deducted for symmetrical antenna mounts pe r the catalog general no tes. Ro hn SSG weig h s 90 pounds per sectio n and can be installed up to 300 feet in 90 MPH winds. It has a gross capacity o f 17.4 square feet in that ma ximum configuration. The Ro hn ginpole erec tion fixture is Photo 5: Apopulated guyed tower at the not rated for SSG because of former XE2DV on theeastern shore ofthe its weight so a mo re suitable one Sea ofCortez. W7ZR was theowner. mu st be used .

Ro tating tow ers A rotating tower is probably the best tower platform fo r installing the ultim ate high performance ant enna system. As yo ur experience and goals increase over time, yo u'll come to realize that the most competitive stations are utilizing stacks of ant en na s, th at is, mul tiple monob and yagis mou nted o n th e same towe r tha t are ph ased together to provide maximum gain and perfo rm ance. T he incr eases in gain, performance and effe ctiven ess are dramatic. Since these ant ennas need to be mounted a distanc e apart, typically o ne wavelengt h, a rotating tower system allows you to turn the whole arra y to aim it at a particular target. As you can im agin e, be sides being the best as well as the strongest, the ro tati ng tower systems are the mo st expensive. You need a spe cial bearing setup at the bottom on which the system turns and then yo u need one or more ro tating guy rings tha t allow th e tower to turn in side of th em. Rotating towers we re first exploited in Finland . O ne of their local amateurs came up with the design and started to manufacture

24

Up THE TarvER

them. N ot only did he make th e ro tatin g guy rings but he also pro duc ed the tow er sectio ns. Sinc e he was a school teacher, he built them ove r th e winter, th en went aro und and installed th em in the summe r. T here are dozen s of these systems in Finland and the p rice was very reasonable; a 120 foot rotating tower approximately fifteen years ago was aro und $1200- installed! Originally designed by Di ck Webe r, K5 IU, his Ro tating Tower Struc tures ro tating tower hardware is now available fro m Paul Nyland, K7 PN, thr u Cus tom Metalworks (www.custom m etalwo rks.co m) . There is ano ther vers ion fro m Rich Bennett, KOXG that is also well designed and beefy (www.K OXG.co m). Both are relatively expensive. And if you embark o n this pa th, you'll pro bably want to use Phillystran non-condu ctive guy wires th at minimize po tential destructive interaction but also adds to the co st. This is not a project for the faint hearted.

Big Berthas T he Big Bertha is a self-supporting tubular rot ating monop ole and it is typically regarde d as th e ultim ate tower. T heir o rigins are fro m th e 50's, and th ey are currently available up to 300 feet (yikes!) fro m Sco tt Johns, \'(13TX at www:superberthaguy.co m. It sits o n a very large block of concrete with a large cylindric al so cket tub e set into it. T he socket is partially filled wit h oil and then the sealed bo ttom end o f the tower is dropped int o the socket where the tower partially floats in the oil, resu lting in very low effort needed to rotate it. Seeing one of th ese works of art in the flesh is an impressive sight.

3 PLANNING When an amateur first get s a glea m in hi s or her eye abo ut p utting up anten nas, it ma y see m th at the "s ky's th e limit." U nfortunately, it's not to o lo ng before realit y, in th e form o f land lim itatio n s, legal, aest het ic, fin ancial and sp o usa l consideration s, alo ng with ne ig hb or and legal complications, set s in. Altho ug h each o ne of th ese o b stacles can b e dealt with effect ively, a fair amo un t of planning is required for any success ful in stallation.

Goals Bu ild ing an amate u r anten na sys te m is an exciting propositio n; starting with a b lank sh ee t o f paper o nly adds to th e possibilit ie s. The first que stion yo u 've go t to ask yo ur self is w hat d o yo u wa nt yo ur statio n to d o? I s yo u r m ain goal to chase D X, handle transcontinental rad io traffic , wo r k VHF / U HF like n ever b efore o r t alk to yo ur buddi es in Ari zona eve ry m orning o n 20 -meters ? Each purpose h as it s own set of possibilities and so lutio ns. You h ave to d ecide what yo u want yo ur statio n to d o. The inform at ion in thi s b o ok will th en

26

Up THE TOWE R

help yo u assemble that station o n ce yo u 've decided. Regardles s of which wa y yo u want to g o, yo u 'll need an tennas an d antenna su p p orts to reach yo ur goal.

Lots, property and acreage N o matter ho w little property you ha ve available, you can get on th e air and have fun. Many articles have been written for apartment and condo dwellers about hidden and indoor apart m ent antennas. If this is your situation, do your homework and do the best you can.

Roof mounted antennas If you have only a small city lot, you ma y want to consider using a chimney or other building features, or putting a roof-mount tower on the roof. Likewise, you can drape wire antennas around th e yard and house and the y'll probably work just fine . It will be challenging and exploiting your limitations might just mak e you a better op erator. After years of operating from world-class multioperator stations, Homer Spence, lORA (SK), decided that the challenge for him was to operate his own station from his ap artmen t in do wntown Seattle, barefoot, with a vertical on top of his building. He was still able to work DX stations around the world while enjo ying the thrill and challenge of operating his modest station.

A small tower If you've go t eno ugh property available (zoning aside), you' ll proba bly start thinking about a tower and similar possibilities. Forty to fifty feet of ROHN 25G attached to the side of your house with ho use brackets will ena ble you to pu t up a beam and give you a plac e to hang wire antennas with a minim um of cost and fuss. Go up an y high er and you'll need to guy th e tower. To put up a guyed 60-fo ot tower, you'll need 1/4 acre or a p iece of lan d 130' sq uare in o rder to acco mm o date the gu y wires and anc ho rs. Fo r a 100' tower, you' ll need 0.6 acre and a piece of land 190' square. (An acre is approximately 44,000 square feet .) In any case , my advice is to go with what you've got and get on th e air. It's much better to have some sort of wo rking antenna than not and if yo u can 't get it very high , it'll still radiate and you'll still be

3-PLAN NIN G

27

on the air. If you've got a fun ky trap vertical, mount it on a fenc e post and start transmitting. Lo ok for possibilities and not limit ations. You'll always be able to im pro ve or upgrade later. Your tower height is up to you, bu t don't forget tha t more he ight means m ore gain and more efficiency, up to a point. Ma ny articles and boo ks have been written with antenna height as th e sub ject and I'm not going to reinvent the wheel here. Again, do your homework and your planning aro und your spe cific conditions and goa ls. I will mention that you sho uld try to shoot for 50-feet as a minimum for H E An effective antenna system on a l OO- foot tower will ena ble yo u to work anything you wa nt and yo u may even win a contest or two.

Taller installations Fo r taller installatio ns th ere are two things to keep in mind. Fir st, o nce you exceed 200-feet above ground level (AG L) you' ll have to comply with FAA regulations for lighting and painting. FAA AdlJisory Circular 70/7460-1H spe lls o ut th ese regul ations. Fro m a practical sta ndpoint, most ham s stay below this heigh t fo r obvious reasons. T he seco nd point is that if you are anywhe re near an airport,

Photo 1:Withtheproper planning, thiscould beyour new heavy metal station. Station built byW7RM (SK).

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Up THE

TO II"ER

you have to comply with the FAA proximi ty heigh t limitatio ns. Contact your nearest FAA o ffice fo r mo re info rm atio n on this one.

Plan ahead At some tim e in the future you may decide to expand your an tenna far m , o r to put up larger arti llery. It's usua lly too late, and/ or too expensive, at th at point to up grade your in stallation . Fo r a relatively sm all additional cos t and effort of a larger hole and more concrete, you can in stall a pad larger tha n that called for by your initial tower. If and w hen yo u ever dec ide to upgrade, yo u'll have a base for a larger tower. Do it while it is easy; yo u'll later likely be co ngratulating yourself fo r being clever and planning ahead!

4 LAND

USE REGULATION OF

AMATEUR RAD IO TOWERS [I have never attended IC/JJJschool, let alonepassed a bar exam. J reIJ on kllollJIedgable attorneysfor legal advice. .And Jampleasedto have permissionfrom CQ to rep rint portions of all alticle 0' ll/) Ialld Dale Clift, NA 1L, nibo is a recogllized expel1 both ill legal andamateur radiomatters, Ivhich hasiI/w illableadvice 011this impol1al/t stlbject.5.M .)

Lo cal, sta te and Fed eral laws affecti ng ama teur radio ante nnas and towers are a result o f co ntin uo us legal developments as new cases are deci de d by the co urts. The m odern era of amateur radio ant enna law was ush ered in by a dr am atic developmen t in 1985 . After year s of sus tained lobbying by the AMERICAN RAD IO RELAY LEAGUE and others, the Federal Communications Co mmission (FCC) ordered limit ed Fed eral p reemption of state and loc al ante nna ordinan ces in a ruling it called PRE-f .! T hat order finally curbed th e runaway trend by loc al govern me nt o fficials to place ever greater restrictions on antenna height and placem ent through zo ning ordinances.

30

Up m E TO fl/I::R

Had this tre nd co ntin ued, it would have meant the virtual prohibition of functional, high freq uency ama teur radio antennas in most cities, towns and villages with zoning regulations. For tunately, the FCC passed PRB -l . But since 1985, the strengths and weaknesses of PRB -l have been tested and examined in several reported court case s. PRB -l got a boost w hen the recent rewriti ng of Amateur Radio Rides inco rp orated the original 1985 PRB- l order into the text of Part 97.15 of the Amateur Rides. But other cases, such as the 1990 decision in th e U.S. Cour t of Appeals for the Fourth Circuit, denied a ham op erator relief from a zoning board of ad justment's decision in spite of PRB 1.2 To the surprise and consternation of ham-attorneys, the court interpreted PRB- l in such a way as to allow the Z BA's dec ision to stand. The ham operator in that case was not permitted to exceed a 17-foot antenna heigh t limit! While this decision is by no means a setback to pr e-PRB-l days, it req uires some readjustments in preparing an application for a tower permit, especially if it in volves a hearing for a special permit. Knowing and understanding the legal foundation of your right to erect an antenna and tower are just as important as knowing the correct construction tec hnique s. This chapter will teach you ab out zoning and building permits. It will also help you prepare for a hea ring if one is required in order to put up the antenna to the height you need. If yo u are well prepared yo u lessen your risk of denial. Hearings are also an op portunity to enhance the public relations ima ge of amateur radio. Every ama teur operator seeking to pu t up a tower sho uld first check out the requirements for obtaining a building permit. Failure to obtai n the necessa ry permits could sub ject you to fines, forfeitures and the threat of arrest . This is not meant to scare anyone, but zoning ordinances and building codes are laws. And anyone who think s he is above the law could find him self on the losing end of a very expensive legal battle. Furthermore, if you do your homework, virtually any ham radio operator who has eno ugh real estate necessary for the safe installation of a ham radio tower sho uld be able to legal1y erect a functional antenna system without interference from state or local governments.

Get copies of the reg ulations first Regulations pertaining to anten nas and the way in which build-

4 - LA 0 USE REG UL ATION

31

ing and zo ning dep artments process permit requests vary fro m town to tow n and co unty to co unty. T he refore, th e first, and mo st important step is to ge t a copy of th e regulations. Ph one the building or zo ning dep artm ent, or go in person to o bta in a copy of the zo ning or dinances . G et th e who le booklet! D o not cut co rners by getting a copy of only those pages you think migh t be applicab le. Even if th e clerk offers to photocopy for you only those pages that pertain to antennas, mak e note o f th ose sectio ns that are mention ed, but do no t accept anything less than th e enti re bookl et. Be wary of stateme nts such as: "This section is all you have to wo rry abo ut." Such statements are not binding on the building o r zo ning department. And the " helpful" clerk can always claim that you mislead him o r her in how you explaine d what you want to do. It is well worth paying for the entire bookl et: it usually costs between $10 and $25. Besides, you need to know a lo t more than just the sectio ns un der which the town regulates antenna heights. You will need to kno w what procedures are followed in applying fo r a permit. You will also need to know how to appeal an adverse deci sion if you do not get a favorable ruling fro m th e build ing inspector or zoning enfo rcement officer on the first try. If you eve r need to seek th e advice o f a lawyer, the first thing he o r she will ne ed to see is th e ent ire booklet anyway. O btain th e en tire booklet of zo ning regu lations now, and study it. This is the building and zo ning department's "bible," and it mu st be followed to th e letter.

"U se" and "dimensional" zoning Be certain you understand what zoning regulations are. Zoning regulatio ns are laws that establish th e uses permitted and the minimum and m aximum dimensional requirements o f structures in established areas o r "zones." N inety-nine perc ent o f th e tim e th e ham operator will want to pu t th e ant enna/tower at his home, which is located in a residential zone. Since the overwhelming majority of jurisdictions hold ama teur radio to be a no rmal, accessory (as o pposed to prim ary) use o f reside ntial property, there is usually no argument that an amateur antenna and tower is a p roper, accesso ry structure for use in a reside ntial zo ne. Swim ming pools, tennis co urts , garages , tool she ds and similar structures are examples of other accessor y structures for no rmal acces sor y uses of residential property.

32

Up THE

TOWE R

A commercial garage, however, is an example of an acce ssory structure use that wo uld not be proper in a residential zone. Ver y rarely do we see cases where th e issues are whe ther am ateur radio antennas and towers are proper acce ssory structures and whether amateur radio is a proper use in a re sidential zo ne. But in addition to use rules, zoning regulations also establish rules as to how high structures are permitted to be . These are dimensional rules. You may find that zoning ordinances require that your proposed antenna/ tower must be held to height, minimum setback rule s and other dimensional limits . Similarly, other " buildings" or "s tru ctur es" must comply with certain ma ximum height and setback rules in a residential zo ne. D imensional limits, pa rticularly height, usually are at the heart of the legal issue in most court cases involving amateur radio antennas and towers . After yo u get yo ur copy of the zo ning o rdinances and ha ve leafed through it loo king for " antenna height," if it is not ap p aren t how antennas are re gulated, do not cele b rate yet. Read the " de finitio ns" sectio n, which gen erally is near the beginnin g o f the zo ning o rdinance s booklet. Sometimes the zo ning ordinances' d efinition of " b uilding" is broad enough to include an antenna/ tower so that the rules limiting building h eight also apply to to wers an d antennas. Of course, an ten nas an d to we rs may b e defined sp ecificall y and thereby be limited. If th e regu lati ons do n ot define an ten n as and to wers specifically, and if th e definition of " b uild ing " does not seem to cover tower s an d an te n nas , see if th ere is a definition of " acces so ry structures." It ma y b e broad eno ug h to includ e antenna s an d to wers.

Building codes Zoning regulations, you will recall, invol ve whether a use is pe rmitted in a zone, and the y establish the dim en sional limits, such as height and pla cement from th e borders o f your property. T he re is yet another aspect to the regulation of your antenna and tower : buildin g codes. Building codes are laws ba sed on standards related to safety that have been agreed upon by engineers from the architectural, stru ctural, civil and other engineering disciplines. T here ha s always be en som e co n fusion because in many municipalities, esp ecially in sm aller towns, building and zo ning functions are co n solida ted in one dep art-

4--LAN D USE REG ULATION

33

me nt, or even one person. T he building offi cial might also be the zoning official or zo ning en forcement o fficer. Even if they are separate departm ents or if th ere are both a zoning en for cement officer and a bu ilding official, th ey usually work in tand em . For example, if you apply fo r a buil din g permi t without eve n checking what the zoning or dinances allow, th e building official will usually run it by th e zoning enforceme nt officer first to m ake sure th at what you are pro po sing is allowed per the zoning ordinances. If zoning ordinances wou ld be vio lated, the build ing o fficial or th e building department will not give you a building permit, even if you me et all the requ irem ents of the building codes. You mu st first m eet zo ning, and th en building req uirements . O nce th e bu ilding official checks wit h zoning and find s that your ante nna / tower is a prop er use in th e zo ne and will not violate the zo ning regulatio ns pertaining to dim en sions, your co nst ruction must be done in acco rda nce with building codes. Fo rt unately, this is rarel y a pro blem . Tower ma nufacturers provide detailed spe cifications and plans for proper installation in accordance with all building codes.

Zoning and building officials A fter you have had a chance to study the zo ning regulations , make an o utline of your un de rstandi ng o f how th e regulatio ns apply to your propo sed ins tallation. If the clerk or secreta ry pointed o ut certain sectio ns to be concerned with whe n you first picked up the zoning or dinances booklet, you may have discovered th at he o r she was right! But now yo u understand and can see for yourself how th e regulations app ly to you; that is what is important. However, if the regulations are making no sense , get help now. Co ns ult a lawyer o r talk with someone who has already gone through th e pr ocess. You should feel confident if you have familiarized yourself with the zo ning or dinances well enough to be able to discuss how and which of th e regulations apply to an tenna towers. Your next step is to call and m ake an appoi nt ment to see the zo ning official and /or the bu ilding official. Which one do you see first? If you live in a sm aller town, the bu ildin g official and the zoning official m ay be o ne and th e same person. In larger cities, th ey usu ally are at least located in th e same dep artment. T he clerk will b e able to direct yo u to the p roper p erson (s). If yo ur town has no t had man y amateur radio operators

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Up TH E TOII''ER

apply for permits for towers, you m ay even find yourse lf referre d to the " town planner," who helped write and adopt the zo ning or dinances and who is usually co ns ulted to help figure out ho w th e regulations apply to a reques t th at is somewha t o ut of the or dinary. If your municipality's ordinances require a hearing, ho wever, yo u will speak with som eone who can add ress zoning issues. Remember, the emphasis for zoning will be dime n sions and use, so be prepared to discu ss the proposed location, height, and purpose of the an tenna structure. Be prepared to discus s building-cod e conce rns , too. For this area of the law you should take alon g ba sic engineering data that is pr ovided by th e to wer manufacturer to satisfy any building-code concerns, and be prepared to discuss ho w it will be anchored and, if required, guyed. It will be helpful to tak e along a drawin g of your property that sho ws the locations of your boundary lines, th e house and o ther buildings, and the proposed loc ation for the tower. If you go t a survey of your property when you bought your house, m ake a photocopy o f it that can be marked up to show the proposed antenna structure. Incidentally, in readin g th e zoning regul ations you may find that you must submit a certified site plan. This can cost several hundred dollars. H owever, you may be able to save th e cost of a certified site plan if yo u have read the zoning regulations carefully. Some zo ning regulations contain a provision that allows you to sub stitute a handdrawn sketch , provided yo u ask for a waiver of the more stringe nt rules calling for surveys and engineering data . The zoning official or boa rd may need to agree first that a certified site plan is not necessary to accurately depict the proposed antenna structure befo re you put in your formal application. Look for thi s provision and, if your town's zoning regulations have it, discu ss it with the zoning official be cause it co uld save you an unnecessary expe nse.

Meeting st rategy The zoning offi cial is going to interp ret ho w zoning laws are appli ed to th e facts of your situation. What he or she says will be the first indi cation o f th e step s th e municipality will want yo u to take to ge t a permit for your installation. Be sure to listen carefully to what th e zo ning official says, and take written notes. Zoning officials are supposed to help you understand the requirements for applying for

4 - LAND USE REGULATIO N

35

a zo ning permit. Again, if you have previou sly obtained and read the zoning ordinance bo oklet and understand the regulations, you are going to get a lot more out of your meeting than if you go into it "cold." T he zo ning o fficial will be more willing to discuss the matt er with you, too, because you have taken the time to study the regulations. If the zoning official starts to say something you interpret to be negative, mak e sure that you understand his or her reaso ning. Even tho ugh this reaso ning may be wrong, listen to it and thorou ghl y un derstand the basis for thi s opinion. E ffective opposition to an adverse position taken by the zoning official will be possibl e onl y if you follow thi s vitally important step. This is not the time to discuss PRB1 with the zo ning official. First of all, he or she is not likely to know what you're talking abo ut. Second, he or she is not go ing to agree with you that their regulation s are flawed. Remember, the zo ning regulation s are the " bible," and the municipality has endorsed the m with the forc e of law. Further, if you are go ing to talk about legal issues, he or she is going to want to talk to their lawyer; wh o is, of course, the town att orney.

Special permits or special uses In many situations, the zoning official will have the authority to grant a zo ning permit witho ut involving any othe r o fficial or board. Then, if he or she is also th e building official, you can get your build ing permit right there on the spo t after filling out the application and paying th e fee. However, depending on ho w your local town's ordinanc es are written, it may be necessary for you to seek the permi ssion of a zoning commission, zo ning board of appea ls, or othe r land -use board. Most often this means that the zoning regulation s are set up so that in order to exceed the " usual" height restrictions, you need to apply for a spe cial permit (also called "s pecial exceptions" or "co nditional use permits"). It simpl y means that drafters o f th e ordinances decided that certain uses or structures can be permitted only after a public hearing and demonstration of special need. If you obtai ned the entire booklet o f zo ning regulations and familiarized yours elf with it, a special-permit requirement will no t come as a shock to you during your visit with the zo ning official. Alth ough a special permit und oubtedly me ans mor e red tap e and delay for the ham operator, such a requirem ent in and of itself is not illegal in the

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Up TH E TOWER

eyes of the law, including the FCC's PRE-I Preemption Order (discussed later) . It does provide a forum for potential opposition from neighbors, however, so preparation for the hearing is all-important. Also keep in mind that the higher yo u want to go with the tower, the more evidence and preparation will be required to establish your need for the stru ctur e.

In case of difficulty If there is a problem, it will be one of two varieties. It may be a matter of interpretation of the ordinance by the zoning official. Or the ordinance ma y be written in such a way that no one could reasonably come up with any other interpretation. If the ordinance is prohibitive under any reasonable interpretation, you should immediately seek the advice of a lawyer. If the problem is that you disagree with the zoning official's interpretation of the zoning regulations, that is not as serious. Though you may need a lawyer to reso lve an issue regarding interpretation, you first can carry the issue your self a little further if you wish. Tell the zoning official that you have a different interpretation, and ask him or her for specific comments. See if yo u can narrow it down as to where the problem lies. If it is a problem with the way in which the ordinance is written-that is, under no possible interpretation can you get your permit-it is the more serious problem. This ma y mean that the ordinance is illegal and, therefore, invalid. The town or city officials won't like that, and they are more apt to fight vigorously against having their ordinance invalidated. They would much rather have to change an interpretation for a particular situation than scrap their ordinance. If you run into an unresolvable problem with the zoning official, inspector, or other supernumerary, you should then, as a last resort, tell him or her about PRE-I . As already mentioned, however, more often than not you will find that it does not help at this level. At most, all yo u can get across is that the Federal go vernment, through the FCC, has acted in this area under a Preemption Order called PRE-I . You can say that local governments cannot prohibit antenna towers, nor can they unreasonably re strict them in terms of size and height. However , it is best not to get into a lengthy discussion of the nuances of the legal doctrine of Federal Preemption with th e zoning official.

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37

A matter of interpretation If there is a reasonabl e interp retation of th e regulations under whic h yo u should be allowed to put up the an ten na l tower, but the zo ning o ffic ial does n o t agree, yo u can us ually apply, get deni ed by the zo ni ng o fficial, an d th en ap peal the zo ning official's decision to a zo ning bo ard o f appeals. T he p ro cedure fo r ap pealing a rul ing by a zo ning o fficia l will be o utl ined in the regulations which , again, yo u ha ve b ecause yo u bought the entire zo ning ordinances booklet, righ t? Bas ica lly, if yo u appeal the zo ning official's decisio n , it m ean s yo u are give n a second ch ance to expl ain w hat am ateur radi o is, wha t kind o f ante nna stru cture yo u want to erect, and what your alte rnative in terpretation is that wo uld p ermit you to er ect your an tenn a ins tallat io n . PRB -l sho uld b e u sed to p ersu ad e th e zoning b o ard o f appeal that it should adopt yo ur m ore rea so nable interpretation. Now yo u sh o uld point out th at Fede ral law requir es to wns to adopt as reaso nable an interpretatio n as p o ssible. If th ere is no possible in terpretation o f the zo ning reg ulat io ns tha t wo uld alIow a func tionin g ama te ur radi o an ten na, then th e zo ning b oard of appeal sho uld be to ld tha t PRB- l is a bin ding Federal regulatio n th at supe rse des th eir own law if th er e is a co nfl ict. T his puts treme n do us p ressure o n the zo ning bo ard o f ap pe al to tr y to ac commodate yo ur n eed s. The zo ning bo ard o f ap peal's interpret ati on of th eir own zo ning ordinances will b e affecte d by the binding order that was ma de by the FCC in PRB -l . T he heart of PRB-l is comprised of o nly a few sent ences, and their importance justifies quoting here: "U po n weighing the se interests [state vs. Federal int erests] we [th e FCC] believe a limite d p reem ption policy is warra nted. State and local regulatio ns that operate to pr eclude ama teur co mm unica tio ns in th eir co mmunities are in direct co n flict with Federal objectives and mu st be preempted." Amateur Radio Preemption, 101 FCC2d 952, 960 (1985) ... "We [the FCC] will no t, however, specify any particular height limitation be low which a local government may no t regu late, nor will we suggest the pr ecise language th at mu st be contained in loc al or dinances, such as mechanism s for special exceptions, variances, or co nd itional use p ermits. Nevertheless , loc al regulatio ns which involve placem ent, scree ning, or heigh t of ante nnas based on health , safety, or aesthe tic

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con siderations mu st be crafted to accommod ate reaso nably ama teur communications, and to repr esent the minimum pr acticable regu lation to accomplish the loc al authority's legitim ate purpose." Id., 101 FCC2d 952, 960 (1985). You can also give the zoning board of appeals a copy of Part 97. 15 fro m your cop y of the Amateur Radio Rides, since this, too, sta tes the basis of PRE-I.

PRB-l and Federal preemption Credit is du e the ARRL for a long-fough t battle to get the FCC to take a stand against overly -restrictive regulation of ama teur radio antennas and towers by ado pting PRE-I. H owever, as you can see fro m the above-quoted passage fro m PRE-l ,whi ch is the "heart" o f the preemption order, PRE-l has its limitations. It holds that no municipality may prohibit amateur radio communication s. It also says tha t state or local regulation s restricting amateur radio antennas mu st do so in the least restrictive way while still accomplishing its legitima te goals. In other wo rds, the local regulations cannot cons titute "overkill." But make no mistake about it, state and local governme nts can, under the spec ific language of PRE-I, regulat e antennas for reasons of health, safety and welfare. But, they mu st balance the local interests agains t the Federal inte rests. Ea rlier, the case of Williams v. City 0/ Columbia, South Carolinclwas menti oned . In that case the radio amateur proposed an antenna system tha t wo uld be 28 feet high whe n retracted and 55 to 65 feet high when fully extended. T he city's zoning or dina nces required anyone wanting to erect an ante nna higher than 17 feet to apply to the zoning board of adju stment for a "s pecial exception." (Remembe r, a "s pecial exception" is just ano ther name for a "special permit" or "conditional use p ermit.") T he radio amateur, Williams, had tro uble primarily because of a rule that a local board's findin g of the fact s is given great deference whe n reviewed on appeal. In other wo rds, the court will not "retry" th e case on the facts unl ess there is clear evidence of unfairne ss or bias. An d proving un fairn ess and /or bias is very difficult. What this case means for radio amateurs is that when you apply for a special permit, special exception, or conditional use permit, it is extremely important to be prep ared to explain the Federal int erests in ama teur radio. For example, if you loo k at the basis and purpose

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of th e Amateur Radio Ser vice you will find that th ere is a Federal purpose in promoting em ergenc y communications, technical advancement, development o f communications techniques, and promoting int ernational goodwill. You must show a relationship between th e need fo r your particular antenna installation and th e promoti on of one or more, and preferably all, of the se Federal interests. It may be obvious to us th at th ere is a relationship be tween antenna height as it affects long-d istanc e communications and your ability to enhance in ternational go odwill. H owever, that will not be o bvious to a zo ning board or a reviewing court. You must establish this "o n th e record" at your hearing. Want to put an antenna o n your tower to access th e ama teur satellites? There is a dir ect relatio nship between adva ncing th e technical and co mmunications art s and your ant en na. And, o f course, your antenna can also be used for emergency communications and drills. You mu st show this relatio nship to Fede ral goals to counteract th e interests th e local governme nt has in regulatin g an antenna system . In m any cases, local government intere st has bee n expressed as avoiding the adver se imp act of the proposed use on th e aesthetic character o f th e surro unding neighborhood , and p romoting health and safety.

Safety, aesthetics, and p rop erty values Now let's get back to th e local zoning o fficial or zoning board . The first thin g to do is to mak e sure that you can establish th at th e proposed ant enna and tower will be safe. On m atters of safety, there can and sho uld be no compromise by th e municipality. If th e installation does not meet building-code requirements, no zo ning board or buildin g official or court will allow it because safety is at stake. The m anufacturer's specification s mu st be followed . Aes thetics and welfare, particularly th e effect o n surrounding property value s, are more likely to be areas wh ere the municipality has to make compromises be cause of the stro ng, co unt ervailing Federal inte rests being promoted by amateur radio. Your task is basically th reefold. You mu st dem onstrate your need for th e proposed antenna and th e safety of th e structure, and you have to show th at yo u have taken reasonable step s to lessen the impact on sur rounding proper ty. The ARRL ha s several helpful papers and pamphlet s. These m aterials include a sum mary and collection o f legal cases fro m aro und

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the countr y.Also, if you need help establi shing th e need for the height of your an tenna, th e L EAGUE has a paper writte n by Gerald Hall, K 1TD, on the relationship between antenna height and th e effectiveness of communications. Finally, th ere is a list o f "voluntee r counsel," attorn eys listed at www:ARRL .org and who are willing to provide an initial consultation to the ham-radio ope rator free of charge. T here m ay be a volunteer counsel near you. At th e very least, you sho uld obtain these m aterial s to help you pr ep are for a hearing. [Contact the Regulatory Information Department, ARRL H eadquarters, 225 M ain Street, Nelvington, cr 06111. p hone: 860-594-0200, fax: 860-5940259} If you haven't already done so, tr y to gauge th e opposition of th e neighborhood prior to a hearing. Be prepared to an swer all reasonable que stions. W hile rad io frequency int erference (RFI) m att ers do not fall under the jurisdiction of th e local zo ning board, your reaction to que stions about RFI might be use d by the zo ning board m embers to judge your character, which could form the un writt en and un stated basis for a denial. A zoning board member is more likely to give the benefit o f the doubt to someone who sounds like a responsible, goo d neighbor. If a neighbor is concerned about RFI, one of the m ost effective ways of dealin g with this concern is to explain that while years ago, the ho mebrew nature of ham statio ns ma y have re sulted in som e ham s being responsible for som e radio frequency int erference problems, tha t is hardly th e case today. To day, th e level o f ama teur radio sophistication is such that RFI is rar ely a problem , and when it is, th e fault alm ost always lies with th e device that is experiencing th e interference. This has been borne out so often that in 1982 the U.S. Cong ress pas sed a law, Public LaIV 97-259, that gave th e FCC th e exclusive jurisdiction over matters of RF I to home electronic devices. The FCC has the expertise to deal with such m atter s, and you the n expl ain to th e zoning board m embers that you would work with th e neighbor and the FC C so th at the y (the zoning board members) wo uld not be shouldered with that problem in the rare event RFIoccurs.

Whe n a tower is impossible T here are some circums tances under which it is impossible erect

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a tower. Co ndo miniums are an example. A condominium ow ner " owns " only th at which exists within the confines of the four walls that for m his or her unit. T he rest of the building and the land are either owned by someone else, or they are ow ned in common by all the uni t holders. Un less you can persuade th e co ndominium association to allow yo u to put up an antenna in a common area, you had better become familiar with so-called invisible antennas or limit ed space antennas in atti cs or crawl spaces above the ceiling. You cannot expect to erect a tower on land or a building th at yo u do not own o ut right. You need the permi ssion of the owner(s). Private restrictions, commo nly called "CC&Rs," which stands for covenants, co nditions and restrictions, are ano ther aspect of antenna/ tower regulatio n that has nothing to do with the government officials. T hese are the " fine print" tha t m ay be refere nce d in the deed to yo ur property, especially if you are in a planned subdivision that has und erground utilities. Your bes t bet before proceeding with your plans is to take a co py o f your deed to an attorney to have a limited title sear ch done for the specific purpose of determ inin g whether private restrictio ns will affect yo u. T his area of the law is the next major battleground since it is diffi cult to find newly co nstructed homes without the se prohibitive privat e ru les.

Local g overnments must be reasonable With respect to governmental, as opposed to private restriction s, it co me s down to one simple fact. Any ham radio operator, provided he or she has a Federal licen se and the private property rights to a sufficie ntl y sized parcel of land, has the right un der Federal law to erect a tower and antenna sub ject to the "reasonable" regula tion of th e local or state govern me nt. The big qu estion, of course, is what is " reaso nable." The majo rity of the court cases interpreting PRB-I have to ld local governments that the y were no t reaso nable in their regulation of ama teur radio an tennas. A US District Court in New York struck down a 25-foot height limitation as being unreasonable and found that the loc al government the re had failed to make a reasonable acco m mo da tio n for ama teur ante nna s.' Ano ther US D istrict Co ur t in Washington State sided with a radio amateur who asserted that the local government was being unreasonable when the ham was un able to get a special p erm it for a 75-foot retractable

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radio antenna." And in California, a U.S. District Co urt invalidated a zoning ordinance governing rad io antennas where the city failed to explore alternatives to a blanket denial of the ham operator's application for a special permit." Since the Williams case, the re has been more encouragi ng PRBI-related news . An Ohio ham operator was awarded his att orney's fees by a Federal judge." And in Colorado another Federal judge invalidated an ordina nce.I T he Boulder Co unty, Colorado ordinance was invalidated because it put the amateur into a "catch-22" situa tion. It req uired the filing of a special-use permit in order to obtain a permit for an antenna taller than 35 feet, but the standards under which special permits were decided virtually assured that you wo uld be denied. T he County has filed a petition for rehearing, however, so this decision was not final as of press tim e. Sometimes a clash cannot be avo ided. Lawyers and judges have just beg un to explore the legal limits of PRB-I. But if you are like most ham operators, yo u want to kno w how best to go abo ut putting up the highest tower yo u can without getting into a big legal hassle. T he key to winning approval is persuading the board or zoning official tha t you actually need the tower you are proposing and have taken all reasonable steps to lessen its impact on th e neighborhood. In the event there is an app eal to a court, the legal arguments nearly always come down to whether yo u have presented enough evidence at the local-board level to show that without the tower you will not be able to communicate effectively. The burden of proving that need gets progressively more difficu lt as you plan to go higher with your tower. In difficult cases a qua lified expert on radio propagation may be necessary. Other factors, such as the neighborhood being "exclusive," can result in your application being put to the test. In these cases the cruc ial factor is whether the ham operator has taken all reasonable steps to lessen the visual impact of the tower on the neig hborhood. In difficult cases, a qualified real estate ap praiser ma y be needed to testify that in his or he r expert op inion the proposed to wer would not adversely affect neighboring real estate values. T hese cases are diffic ult and extraordinary, but I mention them to make the point tha t ham operators sometimes have to be realistic about their plans. When your plans are "ambitious" beca use of the lot size or visua l

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impact to neighbo rs, it requires more preparation to prove need and to illustrate that steps have bee n taken to lessen the structure's impact on surro unding property.

Special problems If you live near an airport, check th e requirements o f Part 97. 15(b) of the A mateur Rules. Depending on your distance from the airp ort and th e length of the lo ngest ru nway, you may need to keep your tower below a certain height or follow speci al rules for lighting and marking it. If you fit certain criteri a, you mu st file both Federal Aviation Administration (FAA) Form 7460-1 with th e FAA, and FCC Form 854 with the FCC and await their approvals. An easy way to avoid having to file these forms is to keep your antenna height below a formula given in Part 97.15 (b). If you live near an airp ort runway more th an one kilometer long (3250 feet), you should keep your antenna height below a slope of 100 to 1. In other wo rds, if your an tenna elevation is mor e th an one meter (3.25feet) higher than th e airport run way elevation for each 100 meters (325 feet) you are located from th e nearest runway lo nger than one kilometer (3250 feet), you must get specia l permission. If the airport runway is less than on e kilometer (3250 feet) in length, you should keep your antenna height belo w a slope o f 50 to 1. In other wo rds, if the elevatio n o f your antenna is more th an two m eters (6.5 feet) high er than th e airport runway elevation for each 100 meters (325 feet) yo u are located from the nearest ru nway that is sho rter th an one kilometer (3250 feet), you must get special permission. Finally, if you live hear a heliport, yo u mu st keep your antenna height below a slope of 25 to 1. In other words, if the elevation of your ant enna is more th an four meters (13 feet) high er th an the helicopter landing pad's elevation for each 100 m eters (325 feet) you are located from the landing pad, you must get special permission. If you keep these slopes in min d, 100 to 1 (long runwa ys), 50 to 1 (shorter runways), and 25 to 1 (heliports), you can avoid special notifications. Simpl y take the distance from the nearest runway or landing pad, and divid e it by th e approp riate slope. For example, if you are one mile away, or 5280 feet, and th e runway is shorte r th an 3250 feet, th ereby requiring a 50 to 1 slope, simply divide 5280 by 50, and yo u ge t 105.6 feet. But if the runway is 3250 feet or longer,

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and the slope req uire ment is 100 to 1, you m ay go o nly to a height of 52.8 feet (5280 divided by 100). There are also so me exemptions fro m th e slope rul e. You can always erect an ante nna up to twe nty feet above th e ground o r above any o the r natural o bjec t o r existing man-made structure (except , o f course, a tower). Be sensible in taking advantage o f thi s exemption. If in do ubt, check with a lawyer. If you live in cert ain parts o f Maryland, West Virginia and Virginia near th e N atio nal Radio As tro no my O bse rvatory at Green Bank or the Naval Research Labor ator y at Sugar Grove, yo u will not be perm itted to increase th e heigh t of yo ur ant enna unless you give wr itten notice of yo ur plan to the Interferen ce O ffice, Natio nal Radi o Astrono m y O bservatory, Box 2, Green Bank, WV 24944. The reason fo r this restricti on is a concern over possible interference to th ese sensitive governme nt facilities. Remember that if you plan to erect an antenna that is high er than 61 meters (200 feet) abo ve ground level, you will always need prio r FCC approval. See Part9 7. 15(a) of the Amateur Rules.

Summing it all up E mphasis from th e start sho uld be o n the mor e practical aspects o f planning a successful campaign fo r getting the necessary approvals for a tower. Be realistic about th e physical limitation s o f you r parcel o f land. Go o n an info rmation gathering mission at the loc al building department to see which offic ials and which regulations are applicable to your proposed antenna installation. Discuss your pl an s with the local zo ning o r building official. D etermine whe ther th e zo ning official's inter pretation of how the rule s will apply to yo ur plans is fair or should be challenge d. Also, de term ine whether a hearing for a spe cial permi t will be necessary. If yo u are dissatisfied with the loc al zoning o fficial's in terp retation, obtain information fro m the ARRL and seek legal advice fro m an attorney as to whethe r th ere is any reasonable int erp retation o f th e regulatio ns tha t wo uld permit you to put up th e antenna/tower. If th ere is no reasonable interpretati on of th e ordinances as th ey stand, then you need to seek eithe r a variance from the regulati ons themselves o r m ake a frontal assault on the o rdinance as being in violation of PRB1. O nce you get into this area of the law, professional legal advice is necessary.

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1 Amateur &dio Preemption, 101 FCC2d 952, 50 Fed Reg. 388 13(1985). 2 IVilliams v. City of Columbia , Soutb Carolina, 906 F.2d 994 (4th Cir. 1990) (1990 US. App. L EX IS 10884). 3 Bodouy v. Incorporated V illage of Sands Point, 68 1 F.Sllpp. 1009(E.DN. Y. 1987). 4 Blllchis v. City of Edmonds, 671 F.SIIPP. 1 270 (W.D Wash. 1987). 5 Hmuard v. City of Bllrlingame, No. C-87-5329 (N.D CaL JIIIY 29, 1988) (1988 1l7ESTLA W 169074). 6 Maouiltan v. City of Rock River, 748 F.SJ/Pp. 1241, 1990 U S. Dist. LEX IS 13591 (N.D. Ohio, Sept.21, 1990). 7 DR Evans v. Board of cOllnty Commissioners of the cOJ/nty of Boulder, Colorado, 1990 U S. Diet. LEXIS 16123 (D. Cole. November 13, 1990).

Glossary of terms Accessory Use, Building or Structure: A subordinate use, building o r structure cu stomarily incidental to and lo cated on the same lo t occup ied by the main use, building or structure. In a residenti al zo ne the house wo uld be the main bu ilding, and its use as a residence wo uld be the main use. G arages, swimmi ng po ols, tennis co urts, and ama teur radio antennas are exampl es of accesso ry structu res. BOCA Code: A set o f engineering standards for structu res established by the Building Officials & Cod e Administra to rs In ternation al, Inc., a nonpro fit standardsetting group based in Illinois. Many states and town s base their own state or town building code on th e BO CA co de, with so me variations. Building: The wo rd "building," as used in local zoning and building regulations, can mean more th an what co mmo n-sense tells you. T he "de finitio ns" sections of some regulation s will define building in such a way as to include ante nnas and other structures. If you find that th e height limitations app ly only to "buildings," check the definition s sectio n before you co nclude th at it doesn 't apply to antennas. Building Code: Th e regulatio ns th at deal with the engin eering, safety and int egrity of structures. Win d-loading standards are part of the bu ilding cod e. Buildin g Inspector: The part-tim e or full-time empl oyee o f th e municipality who int erp rets whe the r your proposed construction co nfor ms with the zo ning regulations and building cod e. Hi s or her interpretatio n can be ap pealed (usually to the Zoning Board of Appeals). If the decision challenged is only with respect to the building code, however, appea l may be to a different board , usually called the Building Board of Appea ls. Larger tow ns may have a Zoning E nforce me nt O fficer (Z E O, see below), leaving the Building In spector to deal only with building code enforcement . Also, don't be surpri sed if there are mul tip le build ing inspecto rs for the electrical and structural aspe cts of yo ur proposed antenna . Building Permit: O nce your plan s have been reviewed , yo u are given the "go-ahea d" in the for m o f a building permit. The pe rmit is usually displayed on the co nstructio n site. Inspections can oc cur at any stage o f con stru ction . Co venants: Private restrictio ns th at wer e placed on the land reco rds by a pr evio us ow ner (usually th e subd ivision developer) that can control eve rything fro m how man y cars you may pa rk in the driveway to whe ther or not out door ant enn as are permitted. Th e covenant s are held to be a private matter between th e

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lot ow ne r and the o the r ow ne rs in the neighborhood for whose ben efit the restrictions purportedly were ado pte d. Covenants are also known as " CC&Rs", which stands fo r cove nants, co ndition s an d restriction s. A title search by an atto rney before purc hase of the lot is the best way to avoid th ese pro blems. Exception: See Special Ex ception or Special Use Permit. Height restrictions: Usually, height restrictions are imposed by a chart of minimum dime nsional requ irements. Other sections of th e regulation s may provi de for excepti ons to the chart. Loo k for a distinction to be made between primary buildings and accessory structures bec ause permitted heigh ts for accesso ry structures may be differe nt . Also , the regulations may provi de that cupo las, flagpoles, antennas, and similar structures are exempt from the height req uirement s. P lanning Commission (so metimes a combined Plann ing and Zoning Com missio n): A land-use board that is charge d with recommend ing cha nges in the districting of zones . It may be charge d with approving sub division pro posals. These functions may be co mbined int o o ne board with the Zoning Commission functions . Co ns ult your zo ning regulation s to determ ine th e exact fun ction of each o f the following bo ard s: Planning Co mmission , Zo ning Commission, (a co mbined Plan ning and Z oning Commission), and Zoning Boar d of Appeals (Z BA). Plot Plan: A dra wing showing the property or lo t, th e structures pr esentl y erected on it, and the locatio n of the proposed anten na structure. Dimen sion s from struc tures and bo un daries are usually required to be indicated. Some regulation s require that th e drawing be accurate and drawn by a certifi ed surveyo r. Before spending mone y o n a surve yor, co nsult the regulation s or building inspecto r to determine how pre cise the plot plan has to be. PRB-l : A declarator y ruling by the Federal Co mmunication s Commission tha t imposes a du ty o n state and local gov ernments to (1) no t p rohibit amateur radio communications with in their municipalities and (2) be reasonable in their regulatio ns to the exte nt that the restrictio ns imposed o n ama teur radio antennas co nstitute the minimum practicable regulation necessary to achieve the municipality'S legitima te goals of providing for the health , safety and welfare o f th e community. Amateur Radio Preemption, 101 FCC2d 952 (1985). Recently PRB-l was cod ified in th e Amateur Rules. See Section 97. 15(e). Preemption: A legal term that indicates that one law takes priority ove r another law: B y the Sup remac y Clause of the U.S. Constitution, Federal law takes prio rity ove r state or local government when the re is a conflict. Special Exception, Special Use Permit , or Conditional U se Permit: A permitted use in a zo ne, bu t o ne which is not auto matically per mitted. In other wo rd s, th e zo ning reg ulations require tha t the appli cant demo ns tra te special need or mee t o the r requi rem en ts to the satisfaction of the Zoning Co mmission. H owever, the land -use board th at passes judgm ent on th ese may be a board o the r tha n the Z o ning Commission, e.g., the Planning Co mmi ssion or th e Zoning Board o f Appea ls. Co nsult yo ur zo ning regulation s to find o ut what th e particular sche me is in your town. It is not un usual fo r zo ning regulati o ns to require a spec ial exce ptio n, special use per mit o r co nditio nal use permit fo r an ante n na. Suc h a requ ireme nt is not illegal per se. However, PRB-l requires th at any res trictions imposed be reasonable. Structure: Th e definiti on o f "s tructure" may exclude such things as cupo las,

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belfri es, ant ennas or oth er things that normally extend above the ro of line. Look for th e heigh t limitation s impo sed o n struct ures o r bu ildings; the n determin e whe ther th ere are any exceptio ns to th ese heigh t limitatio ns. A lso, see "Building" above. Vari ance: A mech anism whereby on e may obtain special relief fro m the zo ning regulatio ns. Usually granted by the Z o ning Boa rd of Appeals (Z BA), the app licant mu st show pr actical difficulties or unn ecessary hardship. T he difficulty o r hardship usually may not be self-imp osed , which aut om atically render s th e amateur radio op erator ineligible for the variance. (But for the fact that th e ham ope rator want s to con str uct the antenna, there would be no hardship, or so the reasoning goes.) There are two kind s of variances: Use Variances and Dimension al Variances. The kind so ught by amateur radio operators are almost always dimen sion al, which mean s that yo u want a variance fro m th e heigh t o r setback requirements imposed by the zoning regulation s. Some states distinguish betwe en the two kind s by making it easier to qu alify for dimension al variances. Othe r states ma ke no distinc tion. Volunteer Counsel: A list of ham radio ope rato rs who are atto rn eys and who have registered with the ARR L as willing to pro vide an initial co ns ultatio n free of cha rge to ham s with ant enna problems. Contact: A RRL H q., Regulatory luforsration Department, 225 M ain Street, NeJlJington, CT 06111. Zone: A district indicated o n th e zo ning map that provides for a un iformity of regulatio n for that par ticular area. It is imp ortant to determine into which zone yo ur propert y lies. Fo r example, one type of residen tial zone may be mo re lenien t by permitting higher structures than ano the r type of residenti al zo ne. Z oning Board of Ap p eals (ZBA): T he land -use board usually cha rged with hearing applications fo r va riances and appeals fro m the int erpretatio n of the building inspector o r zo ning enforcement office r (ZEO). In othe r words, when a buildin g inspecto r o r ZEO is believed to have incor rectly applied the regulation s to a propo sed antenna structure, the app eal is mad e to the Z BA. Zoning Commission (so metimes a co mbined Plan ning and Z oning Co mmission): Th e land use board that established the various zo ning districts and zoning regulati on s and hears app licatio ns for change s in th e toning map s and regulation s. It sometime s hears applicatio ns fo r special exceptions, depe nd ing on the regulation s' par ticular o rganization. The Town Co uncilor Board of Selectm en may not have delegated this law making power to th e Zoning Co mmission, in which case the Town Council or Zo ning Co mmission makes th e decision s as to what the regulation s are or ought to be. Zoning Enforcement Officer (ZED): A full-time o r part-tim e employee of the mu nicipality who is resp on sible for int erpreting th e zo ning regulations and deciding whe the r the particular structure or bu ilding pro posed is allowed in the parti cular zo ne. O ften the duties o f the Z EO are rolled into o ne perso n, th e Building Inspector , who then handles th e que stion s o f bo th the appropriateness for the zo ne and compliance of th e plans to the building co de. Th e decision s regardin g zo ning are appealable to th e Z BA. D ecisions regarding the building code, however, are usua lly appea lable to a special boa rd , usua lly called the Build ing Board o f Appeals.

5 OTHER REGULATORY CON CERNS Stan dard s, compliances an d re gulati ons for tower constr uc tio n keep increasing , m aking it everm o re di fficult and ex pensive for amate urs to put up to wers. T h e co urt an d legal battles th at you re ad abou t in QST, CQ, and eve n yo ur local n ew sp apers are primarily abou t zo ning an d rel ated iss ues such as co ven ants an d othe r restrictions. Even if yo ur p ro p erty is zo ne d to p ermit tower construction, g e tting yo ur building p ermi t h as become m o re difficult as m ore and m o r e cit ies and counties are ado p ting m ore stringen t building regul ations, including the U nifor m Bui lding Cod e (U BC). Yo u m ay h ave to comp ly with st r u c tura l building code s r e lat ed to w in d sp eeds, structural wind lo ading and, in some cases, so il in tegrity if yo ur building d ep artment invokes the U BC. U nfortunately, PRB- l doesn't apply in this process. The vast majority o f tower-building amateurs hi storically have not bothered to actua lly ob tain building permits. Bu t any project th ese days is likely to co me under the clo se scrutiny o f not o nly the local buildin g department but also unfriendly, or at

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lea st uns ympathetic, ne ighbors. G en er ally if yo u put up an unpermitted tower, the o nly way yo u could run into a problem is if a n eighbor complain s to th e building department. Even if yo u are not causing an y kind of interferenc e, they could call and file a complaint . The targe ted department will ge nerally follow-up with, at the least, a phone call. Or worse. During o ne of my many tree-installed yagi projects, my custo m er got a call fro m th e FAA while I was still up in th e tree. A neighbor had sp o tted the new antenna in stallation and felt that we had surely b roken so me law. My cus to m er, an airline pilot, deflected the FAA call by expl aining the situatio n to their sati sfacti on. Next came a call from th e county building department inquiring in to whether he had a permit for the in sta llati on. To ma ke a long story sho rt, th e ne ighbor (th e squeaky wheel) go t the county to insi st th at th e ham need ed a permit for the tree in stallati on. Even though th e building department never cited any bu ilding regul ation for a tree ins tallatio n , the squeaky wheel kept complaining an d , after a nine-m onth running battle with the county, th e ham finally threw in th e towel and bought a building permit. Two months later he got a letter from so meone high er up in th e building d ep artment who determined that he indeed did not need a p ermit and refunded his m oney. In o rde r to placate th e squeaky wh eel neighbor , the building department underlings had "made up" th e requirement. This was the seco nd instan ce o f a big brouhaha surrounding a tree mounted yagi in the Seattle area an d th ey both resulted in the building departments backin g down aft er realizing that tre es weren't covered by either th eir building regul ations or th e UBC. But it just goes to sh ow you th at th e squeaky wheel gets greased. If you've go t antagonis tic neighbors, you'll probably have problems relating to your tower installat ion. O b taining a building permit for a tower m ay go a long way toward keeping th e neighbors at bay. As far as trees are concerned, fo r th e m ost part you can probably just go ahead and do what you want.

Legal help Besides the ARRL Volunteer Counsels previously mentioned, there is an internet reflect or called H am- Law. It 's where th e legal

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eagles hang o ut to discuss tower legal issues. It's open to an yone to join so you can ask a question there and you' ll probably get an answer. T hey do NOT give legal advice but m ay be help ful nonetheless. You can join by sending an emai l to listserver @mail.altlaw.com. T here aren't any archives - everything happe ns in real time . Another reso urce th at is inv aluab le is the zoning book by Fred H opengarten, K l VR, called Antenna Zoning for the Radio Ama teur. It's published by the ARRL and available at most ham radio sto res. He ha s rece ntl y co me o ut wit h a commercial version, the Antenna Z o ning Book - Professional E ditio n: Cellular, TV, Radio and Wireless Intern et. T hese books aren't cheap. The rationale is that it's wo rth abo ut the same as 30 minutes spe nt with a real atto rney bu t is mu ch more comprehensive and available.

Building departments Regardless of whe ther your local building depa rtment invoke s the UBC or another set of buildin g codes, it really comes down to the engineer or permit specialist that you talk wit h who makes the ir inte rpretation of what is needed to co mply with the ir regu latio ns to issue a permit. It is likely that they probably haven't run into anyone building a tower befor e and you'll p rob ably have to start o ut by helping them interpret their regulatio ns vis-a-vis your tow er project. And I' ll guarantee you that if yo u talk to three different peop le in the departme nt, you'll likely get three different interpretations or ans wer s to your questions. Call the office a co uple of time s unti l yo u find so meo ne that seems reasonable that you can wo rk with, th en stick with them. Otherwise you' ll have to educate someone else and they probably have a different interpretatio n anyway.

The Uniform Building Code What about the UBC itself ? T he UBC is one of many building codes used by building dep artm ents nati onwid e as a way of standardizing building codes and compliances. Your building dep art ment may also have additional regulations and complianc es above th e UBC. The UBC set s the standards for structures , which are pri marily buildings. It doesn't specifically take towers int o consideration so you might want to try to convince your building dep artm ent that

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your tower isn't a habit able structure and isn't governed by the UBC. Since that's not very likely, what you're stuck with is to make your tower comply with the UBC. T his mean s your tower will need to me et a wind pressure and ice loading condition for your county as well as concrete foundation, reb ar and grounding codes. A typical specification for wes tern Washing to n State is a wind pressure equa l to a 90 MPH wind with V2-inc h of radial ice. O ne complication that you may run int o is that the manufac turer may use the latest TIA -222 stan dard for calculating wind pressure while the UBC uses a different calculation meth od . Since it's not UBC , the building dep art ment may not want to accept the manu facturer's calculations. A letter fro m the ma nufacturer is one way to get around this problem.

EIA/TIA-222-G The standard that is used by tower ma nufacturers and engineers designin g tower s and tower installation s is the ANSI/ EIA/ TIA-222-G, Stmctural Standard Antenna Supporting Structures and Antennas. T his is the official standard from the American National Standards In stitute, the E lectro nic Industries Association and the Telecomm unications Industry Association and is th e industry bible. The current standard, Revision G, contains the T IA Minimum Basic Wind Speeds for each county in the United States as well as ma ny additional tower specifications. T he lowest windspee d is 70 MP H (the entire states of Kentuc ky and Arkansas) and the highest is 140 MPH for D ade Co unty in Florida.

Building permits and drawings Let's say you do n't have any restriction s on tower erection, your tower will meet the UBC wind pressur e spe c and you want to do the right and legal thing by getting a building permit. In most cases, to obtai n a building permit you' ll need stamped enginee ring drawi ngs from a licen sed local Professional Engineer (p.E.) for your state. If you buy a crank-up manufactured in California that has their stamped tower drawings fro m th eir E E . in Califo rnia, those drawings are generally only acceptable in Califo rnia. T he drawings that you might need could include the info rmation fro m the ma nufacturer regarding wind speed calculatio ns, anc hor/base deta iled construction data and a plat layout o f the installation . Ge tting a E E . to run the calcula-

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tions on your installation and prepare the necessary paperwork to obtain a permit can ru n anywhere from a case of beer if your licensed E E. buddy does them to several thousand do llars if you have it done by an engineering firm . I'd probably budget $250 to $1000 for these stamped drawi ngs . Ask around in your local area to see if there is any E E . that would be willing to do it for a minima l fee. We have a co uple of engineers in my area who charge $60 pe r hour and who budget four hours for the job; this is a real bargain.

Soil tests Alt hough not specifically called for by the UBC, many building departments are now requi ring soil tests . This is to insure that the soil will support the installation and this require s another engineering stamp, this time by a geotechnical engineer. These are not cheap studies. A geotechnical firm will typically charge severa l thousand bucks for this study. If the building department req uires it, you'll need it anywhere you build in the city or county. E ven if you're forty-miles from the nearest town on a mountain-top somewhere, you may be required to submit this in order to get your permit. You can see that although providing this documentation is not difficult, it is measured in hundreds of do llars and is another disincentive for getting a buildin g permit. I work with a local E E. who also does soil tests. Hi s fee of $1500 for all of the necessary paperwork is a bargain; there aren't too many other similarly talented engineers around. Also, if these are the standards now, you can rest assured that the TIA-222 and the UBC will both be continually rev ised upward in co rpo rating ever higher requirements and compliances.

Options? What are the options? Ignoring the law ma y work for you, but any complaint might result in your being ordered to take your tower down . If you've doc umented the base and anchors by taking photographs before the concrete was poured and can provide the necessary engin eering data after the fact, you may only be fined for not obtaining a permit and you can retro a permit. You may want to find a more tower-friendly place to live although these are getting more scarce all the time. Or you might want to bite the bu llet and get the permit.

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Environmental considerations H ere's a wrinkle that's beginning to appear in some place s in the u.s. If you are planning on building your tower on a "wetlands " area, you ma y have to go through a State E nviro nmental Protection Agency (SEPA) review. The agenc y has to de termine whethe r the environme nta l impact is "significant" or " no nsignificant." As part of the process, you may have to put an ad in the paper announcing your plans; interested parties then have thirty days to respo nd. A local contester who was building a new station in western \'{1ashingt on had to write letters to his neighbors in forming them o f his intenti on to put up a tow er. Ju st befor e the deadline expired, he was "invited" to appear before a meeti ng o f all of the concern ed neigh bor s so th at th ey could quiz him about his installation. Fortunately, after telling them abo ut him self, his hobby and the specific installation , their con cerns were addressed and they were satisfied tha t his installation was no t going to po se any threat; their concerns had more to do with cellular and microwave perceived problem s. Citizen gro ups everywhere are inc reasingly fighting cellular and microwave towers on not only aesthetic but also on potential RF radiation grounds. In fact, a couple o f companies tha t manufacture cellular mon op oles have introdu ced mo no poles that look just like trees with sides that look like bark and branches up above just like a real tree just to respond to this citizen sensitivity. So wha t should you do if you're contem plating puttin g up a tower? Eve n if the proj ect is just a gleam in your eye, I'd call the local building department for spe cific permit requirements. Then, I'd get the permit. A building permit is usually good for a year or more and may be renewe d, so you might be 'grandfathered' in sho uld codes and requireme nts change in the future. Since permits will probably on ly be harder to obtain in the future, this may be a good insurance policy for you. If nothin g else, just be aware th at the cos t of putting up a to wer from now on won 't just be the cost o f th e stee l and con crete.

6 NEIGHBORS Your dream antenna system may just be your neighb or's nightmare. To the average sub urbanite, the sudden appearance of a l OO-foot radio tower above the neighborhood skyline will probably raise all kinds of fears and concerns. D o we have a spy living on the block? Will there be interference to my stereo, TV or telephone? What will hap pen to my pro perty values? \X1hat if it falls down? \X1hat if my kids climb up there and get electrocuted? What abo ut cancer-causing radio emissions? We've all heard abo ut, known person ally or read abo ut someone who put up a tower (or tried to) and wound up in court with their neighb ors. We even had a local ham castigated on TV as the "Neighbor Fro m Hell." In the absence of a regulation requiring you to noti fy your neighbors, you have two choices.

The public relations approach Your first option is to be "Mister N ice G uy." I've heard about amate urs who ma naged to get their neighbors involved early on by telling them what th ey were planning to do. These mu st have bee n reaso nable peop le who had their fears and concern s addressed and

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resolved by th e tower own er. You can help them by explaining th at you want to talk to people aro und th e wo rld; bring th em into your shack and show them so m e of your QSL cards or awards. You could tell th em abo ut th e public ser vice aspect and their po ssible need for reliable co mmunications in times o f eme rgency. Telling th em about the phone patches that you handled during Desert Storm would be impressive . The PR approach is a combination o f tact, common sense and patienc e. Co ncurrently you could put up a small antenna and put up a bigge r one in a few months. Or add another tower section a couple of times a year. I've been told that all tower work in th e Faroe Island s was done during stormy wea ther so th e neighbo rs never actually saw anyo ne putting up towers or ant ennas.

No more Mister Nice Guy The second path is to proceed with your p roject with no involveme nt of your neighbors. If you've done everything by th e bo ok, especially obtaining a building permit, there really isn't much that th e neighbors can say abo ut the installation. T he problem s arise when you' ve skipped th e legal and permit p roc ess, th en a neighbor co m plain s to the local building department or o ther authority. At th at point you are bu sted and don't really have an y legal gro unds on which to stand. I personally have found the "Mister N ice Guy" approach to be of little help. When my neighbors didn't like where my tower was going to go on my property, I relocated it and I've regretted it ever since. Now I'm more inclined to refer them to th e building departm ent or FCC if they have a complaint. You decide which way you want to go.

Spouses Spou sal ap proval can some time s be m or e diffi cult to obtain th an neighbors' or building department's. Perhap s you could convince her or him th at this is a dr eam you've had since yo u were a kid (it's pro bably tru e anyway.) It is almost certain ly far cheaper th an that boa t yo u've been looking at; besides, now you won't have to spend all that time hunting, fishin g, golfing, etc . Or maybe this new tower is a good plac e to pu t th at new yard light, TV anten na , birdhouse, whate ver. (H olding m y br eath un til I tu rn blue usually works fo r m e!)

7 HIRE SOMEONE OR DO IT YOURSELF? T he first op tion is to do it yourself. If you obse rve all of the safety practices and equipment in this book, use co mmo n sense in all ins tances, and back away fro m anything with which you don 't feel completely com fortable, you will likely keep yourself out of trouble. In spite of minimal and so meti me s inadequate equipme nt, poor tech niqu e and poor planning, amateur related tower accide nts are amaz ingly infrequent, with accidenta l deaths quite rare. Mos t of these accidents and death s could have bee n prevented by using the proper equipme nt and techniques. Building your own station can be as rewarding as using it. If you're like me, building a reliable tower and antenna system is fun as well as challenging.

Tower service contractor Your second option is to hire a licen sed tow er rigging company,and utilize their experience and equipment. T hey're ins ured, and th ey have almos t certainly done numerous far larger and more complicated projects than a typical amateur installation . They will get it done much more quickly and safely than you will, and it may well be

7-

H IRE SOMEONE OR DO IT YO URSELF

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a most worthwhile investment for you. Altho ugh hirin g professionals may run several hu ndred to several th ou sand dollars, your installation will be done correctly the first time, as well as more quickl y than yo u can do it. A loca l ham had a weekend place where he wanted to build a nice statio n. As he had nev er done anything like this before, not o nly did he have a learning cur ve to go through but also he never did figure out some o f the hardware. He also wast ed time doing som e things twice . H e spe nt six straight weeke nds, travelling two-hundred miles each way to the site, and getting pe ople to help him before he more or less finish ed the project. Hi s wife was read y to leave him . A professional rigging crew co uld have accomplished th e same project in approximately four da ys at a co st o f around $2500. O nly you can decide if it's wo rth it or not. D on't forget, when you pay som eone to do tower or ante nna work, they imme diately fall under OSHA regulations. If you hire someone, mak e sure that th eir safety equipme nt is o kay before you let them near yo ur tower. States now require that wo rkers have a fall arrest system whe n climbing tower s. T his includ es an O SHA approved Class II full bod y harness and fall arr est lanyard . In addition, anyone yo u hire must have liability insurance. In man y states, th ey mu st also be a licen sed contractor. If th ey're not licen sed, you assume all th e risk if anything sho uld hap pen . In fact, if so meone you've hired ha s an accide nt o r cause s an accide nt, you co uld be held financially respo nsible for any dam ages and th e person you hired co uld sue you for any number o f th ings, including not providin g a safe work place. D on't take the chanc e, if the y don 't have the licen sees) and insuranc e, don't hire them.

8 DOCUMENTATION As soo n as you start planning any type of o utdoor ante nna and tower pro ject, ge t yourself a file folde r, a three-ring bind er or so meth ing else in which to keep everything. You 'll have to refer back to your notes and calculatio ns as you go along , so it's easier to have everything in o ne place. Sketches, notes and manufacturer's spec ificatio ns are invaluable add itio ns to your file. Also, keep no tes from all telepho ne conversatio ns, includ ing date and subjec ts covered, espe cially those wit h bu ilding dep artment personnel and others who may be able to in fluen ce your installatio n. A hardware listing of guy wire sizes and type, lengths, mast ID and O D, etc. is also worthwhile.

A picture may be worth a thousand words O nce you get o ut side and start constru ction, take pictures of everything , parti cularl y the civil wo rk. If th ere is ever an y que stio n regarding hole size or materials, photographs can become extrem ely valuable. If a building inspecto r ever wants additional information ab o ut an y aspect of yo ur installatio n, good pictures can likely provide it.

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A few dollars invested no w can save hundred s or eve n tho usands if qu estions about your installation ever arise. And don't just th row those finished prints in a dra wer with your other snaps ho ts; file them in the same folder or bind er with all your other installatio n docume nts. G ood documentation can help yo u so lve station pro blem s. During a CQ\Y/W/ SSB co ntest some years ago , pioneering mul tiopera to r station N 2AA developed a serious pr oblem with o ne o f their ante nnas. Since it was the en d o f Octo be r in New York and it was dar k, effecting a quic k repai r was going to be challenging. Fo rtunately th ey had kept excellent reco rds and in fact fou nd th e potential so ur ce before they even we nt outs ide . Their analysis was correct an d it o nly took a co uple of minutes to fix the problem and th ey were back o n the air. Granted a large multi -tower statio n is pretty co mplex but keepi ng good record s can help any station.

9 COLLECTING THE HARDWARE O nce you 've decided wh at kind of tower you're goi ng to put up, and whe re you're go ing to pu t it, you'll need to start collecting the hardware. By the time you track down all the mate rials and ge t them delivered to the site, you could (and probably will) spend a couple of months in this pha se.

The tower T his part is easy. O nce yo u've decide what you want to put up, all you have to do is call up the retailer or manufactur er and order it. R OHN puts out packages of 25C and 45C that include additional hardware such as guy wires and torque arms that will save you some work.

More hardware If you're going to track down everything yourself, plan on spending lo ts of time on the phone or on the internet. O ne place that can prove to be invaluable is a local so urce of scrap me tal. T here are likely one or more good salvage yards in your area; a few ph one

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calls and visits can give you an idea of what they can provide. Many tim es the y'll have galvanized angle iro n, tubing and pipe as well as stainless steel and aluminum. It doesn't hurt to stockpile some o f this stuff because it'll be real handy at some point in the fut ure, and chances are pretty good that if you go back to get some, it'll be gone. Ano ther tremendou s help is a goo d fastener or nut-and-bolt store. Their main market is ind ustrial companies, so they'll likely be in the industrial part o f town. Again, the Ye//01V Pages wit h a few phone calls and visits will give you an idea of what's available. Two excellent online resources are Grainger Industrial Supply (www.grainger.com) wh o seems to have just about everything, and McMaster-Carr (www.m cma ster.co m) who also has an ext ensive line of products.

The hardware maxim Not only mu st you use the correct hardware for the application, but also it mu st be made from the correct material. The only accep table materials for tower constructions are: Galvanized: Steel parts are hot-dipped when galvanized and can be recogn ized by th eir dull, rough grey finish . A stock of galvanized nuts, bolts and U-bo lts is vel)' desirable. Galvanized and nongalvanized nuts and bolts are not compatible. T he galvanizing process leaves a thin coating of zinc on the threads that will not take a no rmal o r stainless steel part . You must use galvanized nuts with galvanized bolts. There is also galvanized hard ware available th at has been plated rather than hot-dipped. The finish is shinier and not as thic k as the galvanized o ne. Antenna hardwar e U- bo lts are commonly thi s variety. They're no t as long lasting as the hot-dipp ed o nes but are acceptable in most cases. Stainless steel: Stainle ss steel (SS) nuts and bo lts are more common than th e galvanized variety but are ge nerally more expensive. You can also sometimes find SS tu bing, angle and plate at your local salvage yard. It is a relatively hard material, making it difficult to cut o r drill but it can be real hand y in man y instanc es. Aga in, a stash of vario us SS materials can come in handy. SS nuts and bo lts can gall easily, which resul ts from one m etal losing metal to another because o f heat o r molecular att ractio n res ulting from friction. The nu t and the bo lt fuse together and th ey're imp ossible to remove. You either

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have to grind them apa rt or break th em off to separate them. If you use a little bit of grease or lubricant on the threads , you'll minimize this problem. Aluminum: Alumi num ang le, plate, tub ing and pipe can be handy as well for creating mounts and other appurtenances. It is easy to fabricate and can be used for lo ts of mounting and installation solutions. The biggest problem in my opinion is that aluminum is soft and can be damaged by rubbing against a harder material, such as steel. This is what can hap pen to an alum inum mast that is drilled and pinned with a 55 bolt to lo ck it to the rotator. T he constant wind pressure can cause the ho le to gall, o r enlarge , and fail over time. In general, be wary of any unidentified material, particularl y if it's going to be used in a critical application. If in do ubt, don't use it. Also, if you're not sure about the suitability of any hardware, leave it outside for a few weeks and see what happens. If it starts to rust, recycle it over the back fence or take it to the dump; just don't use it.

Additional hardware Here is some additional hardware that you 'll probably need (when I need to buy something, I always try to buy at least a few extras to add to my spare hardware collection; I encourage yo u to do the same): Clevises: A clevis is a device used to couple things together. It is generally U-s haped and has a pin to connect the holes at the two ends of the U. It functions just like a carabiner but has a removable pin that screws into the clevis body. Clevises are sometimes also referred to as shackles. \X!hile you can get clevises in many different sizes and capacities, their main drawback compared to a carabiner is that it consists of two pieces and one of the pieces can be accidentally dropped. They should be used in places where you need a permanent coupling, such as between the turnbuckle and guy anchor or between the tower guy attachment and the gu y wire thimble. Clamps: Cab le clamps are used to clamp two pieces of wire together. Their most common use is to secure a guy wire tieback. This is where the guy wire is bent 1800 and clamped to itself, producing a loop for attachment to another part of the guy wire system . You should always use a minimum of three clamps on any f:,ruy wire tieback. Thimble: A thimble is the device that goes into the loop of

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th e guy wire tieb ack . Its purpose is to evenl y distribute the strain on the guy wire loo p. All-thread: All-thread is threaded rod stock. It is available in stainless ste el, galvanized and plated finishe s. Mo st hardware stores carr y it in fou r o r five-foo t lengths. It can be very hand y for tower ancho r bolts or o ther application s.

10 CORROSION Co rros ion is o ne of the biggest problem s in tower and anten na installations. Knowing more abo ut it will help you to use appropriate materials and stay away from problem atic ones. In its raw for m, metal is usually found in ore. E nergy is added to the metal in the extraction process. In th e long ter m, me tal ret urn s to its natural , corroded state when it gives off the added energy. Any metal by itself will eventually oxidize due to exposure to th e oxygen in the atmosphere. The aluminum in our ante nnas creates the powde ry alum inum oxide yo u find whe n you take an ante nna apart, while steel oxidation produces the rust th at you want to avo id.

Bi-metallic corrosion When two m etals with the right properties are in contact in the presence of an electro lyte, bime tallic corrosion takes place. It's th e same chemic al process th at takes place in batteries. Spec ifically, electro ns from on e metal (called the ano dic m etal) flow acro ss the joint or junction to the o ther metal (called the cathodic me tal). In bime tal-

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C ORROSION

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lic joints, the more anodic metal is always the one that corrod es. The electrolyte is typicall y some kind of salt or other co mpound (such as zinc) dissolved in water makin g th e solutio n co nductive . Rain (particularly acid rain), mist or co ndensation are suffi cient for bime tallic corrosion to begin .

Galvanic incompatibility G alvanically incompatib le metals are ones th at readily corro de whe n in co nt act wit h other metals bec au se o f thei r ranking on th e galvanic chart. When you mus t use different materials, it is best to use metals th at are close together o n th e ch art. You can see th at on a zinc galvanized tower, alumin um and mild stee l are th e most co mpa tible. If you use materials such as copper and brass when in stalling your tower gro und system , you can see that you will ha ve pr ob lem s with co rrosion almost immediately.

An tioxidants Vario us compounds are available for combating co rros io n. These are antioxida nts and most commonly used metals ha ve several products designed spe cifically for each of them. Fo r alumin um anten na s, most manufacturers p rovid e a packet of antioxidant with th eir products. Ret ard ing oxida tion is no t only a good electrical ide a but also it fu ncti ons as an anti-seize when you go to take th e antenna apart in th e future . These antiox ida nts are so metimes incorrectl y called "cond uctive past es o r g reases." In gene ral, th ese antioxidant compounds are co mpr ised o f a vehicle material with m etallic chips in suspe nsion . It is these condu ctive chips, not the vehicle material, that give it its conductive properties. What hap pens is that the particles will pierc e the layer of oxidation whi le preventing corrosion by isolating the joint fro m th e air. BUTIERN UT'S " BurrER-IT's-N oT" uses co pper du st in a m olybdenum suspens ion whil e M 2 pa ste use s copper and graphite flakes in a petroleum base. T here are othe r commercial produ cts availab le for co pper joints which should be used o n ground systems . Just be certain to use the right one fo r the job. While you can see the obvious positive effe cts o f th ese compounds on ante nnas and ground systems, yo u should also use so me

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type o f grease o r an tioxidant inside th e legs of your tower secti ons. Not o nly will it make assembling th e sectio ns easier as the legs slide togeth er, when you take it down, th e antioxidants will have made your job easier since th e legs wo n' t be seized up du e to ox ida tio n. Relative Galvanic Series In Sea Watcr ANODIC END Magncsium Zinc G alvanized steel Aluminum Mild St eel Iron 50-50 lead/tin solder Stainless Steel Tin Nickel (active) Brass Alumi n um-b ronze Copper Nickel (passive) Silver Gold

CATHODIC END

Rust Steel towers and hardware will rust unless steps are taken to prevent it. In the case of towers, they should be galvanized steel or aluminum. Hardware, including U'- bolts, nuts, bolts and other fasteners shou ld either be made out of stainless steel (SS) or be galvanized. Because the galvanizing process deposits a thin coating of zinc on the hardware, you can't interchange SS and galvanized nu ts and bolts. Surface ru st is ru st th at is either dep osited whe n you have wa ter fro m a ru sted piece of hard ware run down a surface such as a tower leg or active ru st th at hasn't yet pen etr ated the layer of galvanizing. Neither condition is serio us but you should repair those sp ots during yo ur annual inspection. J ust tak e yo ur wire brush to scrub off the ru st and the n spray the sp ot with a co ld-galvanizing paint. Co ld-galv, as it is called, is available at almost any spray paint rack. Look at th e contents to make sure that it's got zinc in it. T he LPS COMPANY ma kes a very good cold-galv spray that is relatively exp en sive (ano ther case

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o f ge tting what yo u pay for) but adheres very well. Besid es using antioxidants o n towers and ante nnas, the y sho uld be used in ground system joints as well as in marine environments.

Connectors Since just abo ut every coax join t you use will be a PL-259, N connector o r F fitting, my recommendation for o utdoor use is to use th e silver connector s in stead of the nickel plated variety. \'(1hen nickel oxidizes it produces nickel oxide, which is a nonconductor: whereas silver oxide is a conductor.

Antioxidant products Because mos t antioxidant products are usually available only fro m various spe cialized distr ibutors and suppliers, it is not pos sible to walk int o your local hardware sto re and exp ect to see much o f a selectio n. The following list o f manu facturers and suppliers sho uld be of some help :

Ma n u facturer: B EI' Cl IER, I NC.

241 Depot St Antioch, IL 60002 Ph: 847-838-3 195 Fax: 847-8 38-3479 www.bencher.com Product: Blltter-Itc-N ot Source: Direct, if no t stocke d by local author ized dealer No te: Contains copper dust in a mo lybdenum suspensio n Manufacturer: GB ELECTRICAL Ga rdne r Bende r PO Box 3241 Milwaukee, WI 5320 1-3241

68

Up mE mlr'ER 800-624-4320, pr ess 1 www.ga rd ne rbc ndc r.co m .' Product: OX-CA RD Source: Available from many electric al supply hou ses and retail o utlets such as Home D ep ot and ot he r hardware sto res Manufacturer: ID E AL IND USTRI ES , IN C. Becker Place Sycamo re, IL 60 178 USA 800-43 5-0 70 5 www.id ealind us tr ies.co rn Product: N OA L OX Source: Available from so me hard ware sto res and supply hou ses N o te: Contains zinc particle s suspended in a carrier Manufacturer: SAN CH E~I, INC. 1600 S. Cana l Street Chicago, IL 60616 312 -733-6 111 www.sanche m .com Product: N O-OX-ID ';A-SPE CIA L" Source: Direct from manu factur er Manufacturer: TI I O ~IAS & BETrs CORPORATION 8155 T&B Boulevard Memp his, TN 38 125 Ph on e: 90 1-252 -8000 www. thomasandbetts.com Pro duct: A/llma-Sbield So urce: Available from many elect rical sup ply houses N ote: Co nta ins zinc particles suspended in a petr oleum base Manufacturer: FC l Versailles, Fran ce h ttp :/ / po n al.fcico n ne ct.co m / Prod uct : BII17Idy Penetrox So urce: Available from man y supply hou ses and some retailers N o te: Z inc particles suspe nded in a natural ba sed co mpo und Manufacturer: ILSCO CO RPO RAT ION 4730 Madison Road Cincin nati, O hio 45227 5 13-533-6200 Product: DE -OX Source: Available fro m electrical supply hou ses Note: Green co lored grease with no noticeable particl es in suspensio n

11 FOUNDATIONS AND GUY ANCHORS Fo unda tio ns and anchor s that are installed in th e earth provide th e most basic and important structural part s of th e tower so having th e co rrect foundation and anchor s is vitally important. The purpose of the base in a self-suppo rting tower is to move the center o f gravity o f th e tower below the gro und and be big eno ugh to exceed th e overtur ning moment o f th e wind pressur e against the tower. The purpose o f the ba se in a guyed tower is to ba sically keep th e base from sinking in the gro und. T here's virtually no overturning moment with a guyed tower since the guys take the hori zontal wind forces. Acc ording to their "Encyclopedia o f Ancho rs" (available free from the A.B. Chance Co. - 573-682-8414), there are nine soil classifications of soil make up and structural capacity. While a discussion of the exact values and me asu ring techniques are o ut o f the sco pe of thi s bo ok , th e soil classification dat a gives you so me idea o f the problems that can be encoun tere d when designing appropriate earth anchors. T he o nly way yo u can get an accurate profile of yo ur soil is to pay for a geotechnical survey. It's relatively exp ensive and involves digging several holes with a backhoe to expose the earth.

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For ver y basic purposes of this book, soil and its loadbeari ng capacity is divided int o three main categories: no rm al, rock and sand . Normal soil - Normal soil can be made up of loam, clay or just about anything that isn't rock or sand. Roc k - Spec ial design considerations need to be taken into account when dealing with either roc k or sand . Rocky ground is usually either solid roc k, like gra nite, or shatte red, where you have soil aro und the rock bu t no t enough to be able to excavate easily. Either way the rock itself can provide a very secure anc ho r. Rock can be dri lled, whic h gives you two optio ns fo r your anchor. The first is to use rock exp ansio n bolts. These use mechanic al pressure to hold them in place . They are very stro ng and will provide a bombproo f rock anc hor. T he other option is to use suitable sized all-thre ad o r suitable ancho r bolt (available at any hardware store), th en epoxy it int o the hole. T he re are spe cial industrial epo xies that you sho uld use. Co nt act a local rock anchor supplier for m ore inform ation on these two metho ds. (These techniques work very well for concrete as well.) You co uld use the rock itself for the tower base and anchors as well. \X1hy would you jackhammer away a bunch o f rock for the ba se and then pour concrete back in the hole when you've already got some nifty rock just sitting there ready to use? After ensuring that the rock is indeed big enough and intact eno ugh to be useful, you can either drill right into the rock for base anchor rods or pour concrete over the rock to make a nice square form. T he concrete and th e rock need to be joined so you'd need to drill a su fficient number of holes for an adeq uat e number of pieces o f rebar to bond the rock and co nc re te to gether. An engineer should calculate hole and rod sizes and design. Photo 1:Typical self-supporting base with rebar, base There ar e a section and ground level form.

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number o f tools available for drillin g in ro ck including a jackha mmer, an impact hammer with a coring bit or hand-held rock drill. Check with your loc al rental sto re and see what th ey recommend.

Sand Sand presen ts anothe r problem because it has very little hold ing power. Larger than normal concrete anchors cast with the co ncrete block sitting partially o ut o f th e gro und is one optio n. T his type is usually poured into a form and th en backfilled aro und it. If you use a large enough blo ck of concret e, it wo n' t go anyw he re. A big dea dman can also be ins talled. T his is a buried anchor with a big plate o r dish buried at the ground en d. Again, co ns ult with an engineer to insure the holding power o f these anchors.

Forms The o nly co ncrete for m you really need is for the part that is ab ove ground level. You can just use so me 2x4's to m ake a nice rectang ular fo rm th at is slightly tilted to allow water to run o ff. T he po int is tha t if you make th e fo rm perfectly level, th e wa ter will pool instead of ru nning off. For larger bases, the concrete may sag in the midd le of the base so take extra care to provid e a water pa thway o ff th e top of the base. D o no t use a form in th e hole unless th ere is a structural problem with the so il; e.g. river bottom rip rap th at is prone to slo ughing. T he tower specs call for the co ncrete to placed against undisturbed soil so no form is needed in the hole.

Siting the tower and guy anchors If you're going to pu t up a self-s upporting towe r, all you have to worry about is the bes t spot to locate the base. Practical siting co nside rations include excavator and co ncrete truck accessibility and pr oximity to ove rhead power lines. You'll also want to avo id buri ed power, telep ho ne, gas, water and sewe r lines along with septic tank s and dr ainage field s. If you don't know th e location o f any of these, its a always a good idea to pho ne you r loc al utility companies, o r better yet, "CALL BEFORE YOU DIG" or 'V;\'DERGRO UND UTILITIES" services as listed in your lo cal phone directory. These serv ices, using an 800 number, cover m ost areas of the U.S., and pro vide centralized datab ases fo r all utilities in the ir regio n. You give th em the exac t

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ph ysical addr ess of the locatio n where you plan to dig; if it is in their data base they will send computerized noti ces to every utility which co uld possibly be affected. T his can range from two or three in a rura l area to as ma ny as fifteen in a dense urb an neighbo rhood . T he utilities then have 48 hours (this may vary in differe nt regio ns) to send out the ir loc ating crews to identify any buried lines. T here is normally no charge for this service, unless you call to tell them you plan to dig the next day, in which case there you could be charged fo r "emerge ncy service." To tes t this service, I phoned in an address in the small tow n in wh ich I live. Their co mputer came up with eight utilities that needed notifi cation: the city, the water district, th ree telepho ne companies, the po wer company, th e gas co mpa ny and the state dep artment o f tran sportatio n. (It wo uld never have occurred to m e th at so many folks could be int erested!) If you have tro uble find ing a 1-800 number, phone any local utility; th ey'll be able to give yo u the number for your area. Fo r a guyed tower, you mu st make the same evaluation for th e base and then determine where your gu y wire ancho rs should go. T he easiest way to select the optim um site it is to take o ne of the tower sectio ns and stand it up in o ne of your chosen spo ts. T he n loo k through the tower face to the opposite leg and yo u can see the pla ne of the guy wires. By loo king at all three legs, you can see if you r anchors are goi ng to be in the clear. If they're not, simply lift up your tower section and rotate it until yo u've go t the guy anchors located where yo u want the m. Be sure to check for any trees in the guy wire lane s. Next, take your tape mea sure and go out the desired distance (80% of th e heigh t of the tower is a minimum) and mark the spo t. Do that for each guy an chor and you're all set.

E xcavation Now you've got so me soil to move. You co uld do it the old fashioned way with a shovel and wheelbarrow if th e hole(s) aren' t too big but it's much easier to make a ph one call and either hire a contractor or have an excavator delivered by your local rental yard. D oing it yourself is fun and easy. You need an excavator with eno ugh reach to dig down far eno ugh. T here are plenty o f Kubo tas, Bobcats, etc. available and within 10 minutes you' ll be doing a decent job.

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Photo 2: Buildinga rebar cage.

You need to decide what to do with the excavated soil. It fluffs up when it's dug up; a 5-cubic yard hole is going to produce abo ut lfl-cubic yards of soil. I always have th e excavator do several more jobs besides digging the ho le(s). You' ll need it to move the heavy rebar cage (50-200 pounds in so me cases) to the hole and lower it in. You may need it to hold the bottom tower section or base fixture in the hole so you can attach it to the reb ar cage and level it. You might ne ed the excavator to un load th e tower and /or move it to the ho le. I always prefer to use a piece o f equipm ent rather than manhandling so m eth ing he avy and awkwa rd and I reco m mend you do the same .

Reinforcing bar After you've got everything sited, dig the holes spe cified by the manufacturer and install the required reinforcing bar, o r rebar, Reb ar is spe cified by a size; #2, #4, etc. T he sizes refer to eight hs of an inch . For instance, #4 rebar is 4/s" o r V2", #6 rebar is 6/8" or %", etc. The most common is

Photo 3:Thefinishedcage after acouple of hours. Note the X bracing on each face. The extra lengths will be cutoffwith a hand grinder.

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#4 (W ') . Get the size the manufacturer calls for and install your rebar in the hole in the pr escribed manner. Fo r rebar cage s, yo u'll probably need to do a littl e bit of b ending and cutting b ut it's pretty stra igh t fo rwa rd. Yo u' ll ne ed to wire the re ba r togeth er and you can ge t roll s o f tie wire or baling wire for th at at any h ardware sto re. If yo u' re go ing to ha ve yo ur base an d anc h o rs ins pected b efore Photo 4: Lowering the rebar cage with a th e conc rete is poured, the backhoe. Note nylon slinguse. insp ecto r will wan t to en sure that th e re bar do es not to uch th e so il o n the bottom o r sides. O th erwi se the rebar will ru st away and degrad e th e integ rit y o f th e anc ho r. If th is is a large ho le for a good size d self-s uppo rte r o r cra n k-up, you m ay wa nt to have your rebar cage fabrica ted and in st alled by p rofessio nals. Reb ar is fairly ha rd and can be difficul t to cu t. Use yo ur circular saw and aggregate cutting blade o r han d g rinde r (do n't for get yo ur safety glasses) to cut it effi ciently. A reba r cage made up o f hori zontal and vertical pieces has little to no stability so you'll ne ed to add additional pieces of rebar on each face in an X co nfiguratio n. T his will stiffen th e rebar cage up significantly.

Guy anchors The ROHN spec ificatio ns for ancho rs calls for o nly I/ Z yard of co ncrete with the hole refilled with dirt, o r backfilled. D irt, o r no rmal soil, offers almo st as much integr ity or strength as the concrete does so backfilling minimizes your concrete requiremen t. Some peop le dig th e prescrib ed hole and then go ahead and fill it with concrete. This is o kay too, just a little mo re expensive. T he to tal co ncrete called for by ROHN for a base and three ancho rs for a 25G tower is only 2.5 cubic yards. As man y co ncrete co mpanies have three or fou r yard

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rrururnum s, you may wa nt to have a use for the excess or mix it yourself, which is a lot o f work!

Tower base If you're installing a round-legge d tower, such as ROHN 25G or 45G, pu t at least four inches o f sand in the bottom of the hole for water dr ainage. Rain water and conden sation will run down the inside o f the legs and it needs some place to dr ain. If it can't drain out, the water will start to cor rod e th e in side o f the legs and can eventually eat th rough th e m etal and you' ll never see it because it's on the inside. Also, if yo u have standing water in th e legs, a goo d win ter storm can freeze the trapped water and the ice can split the legs. Some tower manufactu rers offer a cement ba se sectio n or base bolts that are designed speci fically to be installed in the co ncrete base. Fo r crank-up towe rs, be sure to use th e manu factu rer's spe cs or manufactured base sectio n. If yo u are pu tting up a used tower, such as BX, 25G or 45G, and don't have a genuine base sectio n, simply bu ry a sectio n o f the tower itself in the concrete. When you move, just hacksaw it off at the top of the base and use it for the next base sectio n. Alth ough your tow er will shrink a few feet each time you reinstall the towe r, this is still a pr actical thing to do. If you are putting up a used cra nk- up and don't have a factory concrete base fixture to install, you mu st use exactly the same size and grade of hardware th at they spe cify. Again, do what the m anufacturer says. Call the m for more information. If you have an y questions about your installation, ge t a licen sed Professional Engineer involved .

Concrete c onsiderations Now that you've go t th e hole du g and the reb ar cage installed , it's time to call the building inspecto r. If an inspection isn't required, then you're ready to or der th e co ncrete. A typica l tower co ncrete spec calls for 2500- 3000 psi strength. You just call your local co nc rete supplier and or der it. You wo n't need an y accelerants o r exotic mixes, th e standa rd mix is fine. E nginee ring spe cs call for 28 days for a full cure. Ke ep th e co ncrete damp for maximum stre ngt h. H ere's an easy way to ge t your tower installed faster by decreasing th e cure time . Instead of th e typical 2500 psi co ncre te, orde r

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5000 psi . It's only slightly mo re expensive an d it'll cure to 50% of its specified strength (2500 ps i) in 4 days at 70 deg rees F, thus saving yourself weeks of cur e time. T he easiest scenario is if the concret e truck can back righ t up to the hole and chute it in. In 15 minutes it'll be poured and all you have to do is finish th e top o f it. If th e truck can't back up to the hole , you can eithe r get your buddies over to hump it with some wheelbarrows or you can call a concrete pumping company. T he most economical concrete pumper is a trailer or truckmounted line pump. It can pump up to 400 feet and can be used in most situations. A snorkel pum per is useful if you have to go over something but is ge nerally mo re expensive. It takes a smaller gravel size in orde r to be pumped thru the ho se so be sure to let your concret e supplier know if it's being pumped. T he pumping company wo rks with the co ncrete batching plant all th e time so they might be able to coordinate it for you.

Leveling the base section using base bolts Leveling the tower is a very imp ortant initial ste p. There are two types o f base attac hme nts meth od s: 1) a base using threaded anchor bo lts or 2) a base using anothe r method: e.g. with hollow ro und or angle legs. Anc ho r bolt s have the advant age o f being able to ad just the tower plumb using th e leveling nuts o n th e anchor bolt s. This way the an ch or bo lts don't have to be perfectl y plumb - you hav e a good am ou nt o f adju stment even aft er th e co ncrete has hard ened. Many time s an ancho r bolt templ ate can be made insuring proper fit whe n you install th e tower. A plywoo d woode n template or a welde d anc ho r bolt fixture can be burie d in th e co ncrete as it's a o netim e use devi ce. O ne way to make an anc hor bol t fixtu re is to attach and tigh ten the anchor bolts to the bottom section or base fixtu re (as in th e case o f a crank-up) and th en with the ancho r bolt s sticking out horizon tally, they can now be welde d together. Rebar or any scrap metal lying around will suffice for the anchor rod braces. Weld th e metal br ace pieces between each leg in two rows. Weld one row near th e bottom of th e bolt s and th e o ther row near the top, but not so far up that th ey'll stick out of the co ncrete. Once th ey're welde d, the ancho r bolt fixture can be removed and secured int o the hole in

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prep aration fo r the co ncrete pour. Dealing with this ancho r bolt fixture is mu ch easier th an wres tling aro und th e ancho r bolts attached to th e bas e fixture. Next, secure the ancho r bolt fixture to th e reb ar cage with tie wire. Lie o n the gro und and look across the top of the wooden hor izontal forms to insure th e ancho r bolts will stick out of th e finish ed concrete adequately. You can lay a 2x4 across th e top of th e bolt s and put your bubble level on it to check for level. Leave six to eight inches of bolt sticking out, or mo re if yo u ne ed it for the ba se and leveling nuts. Take th e nuts off o f the anchor bolts and tape th e th read s with electrical tape. That way, you wo n't get concrete in the threads during the po ur. \XThen you're read y to install the bottom section, put a leveling nu t on first followed by a large washer, if necessary, and run it down the thr ead un til it is an inch or so above the top o f the co nc rete foundation. Now lower th e section or base into plac e and pu t on the top was her and nu t. By tightening or loosening the bottom leveling nuts, you can plumb th e tow er at anytime. You can do the first section righ t away and th en mak e an y adjustmen ts to plumb as you finish the inst allation. For large self-suppo rting towers, a transit sighte d o n two legs will give you an accurate result . Tighten up the to p nuts and you're all done.

Leveling the base section of other towers T here are two ways to level the bottom section of a tower that doesn't have base bolts. Any tower base requires some sort of rebar cage. You can tie the tower section th at is go ing to be encased in th e co ncrete to the rebar cage to stabilize it and th e rebar. Next, ru n a temporary piece o f rope from each leg to a stake 6-8 feet away from the leg. You can ad just th e temporary line s with a co mea long to hold the section plumb while th e co ncr ete is being poured and until th e concrete sets. You can use eithe r a bubble level o n each leg in the case of a guyed tower or suspe nd a plu mb line fro m th e middl e of the tower fo r a tapered self-suppo rting tower. I just use a piece o f string with a big nut on the end of it for my plu mb line. Since all it is is a vertical reference point, it doe sn't make any difference wh ere it is installed in the tower. O nce th e plumb line is still and not moving, simply sight

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through th e oppo site face along a leg edge and ad just your temporary ro pes until all of th e legs are in-lin e with th e plumb line . If th e wind is blowing your plumb line around, put the bottom of it in a bucket o f water and it'll stay pu t. Whil e a bubble, o r spirit, level can be fairly accurate, an electronic level will give you plumb within 1/ 10 of a degr ee fo r really accura te results. T he only thing that's plumb o n a tapered towe r is th e right and left edge of th e leg as you're facing th e leg so that's where you p ut your level. Ano ther method is to shoot it with a tran sit. In any case indu stry standards let you be out of plu mb 3 inches per 100 feet fo r a guyed tower so you can be o ff slightly witho ut causing a fatal probl em .

Guy anchor options You m ay want to put in an elevat ed guy anc hor. T his is useful if yo u don't have eno ugh distance to your guy anchors (this basically red uces the length a foot for every foot of vertica l of you r eleva ted anc hor) o r if you want to have your gu y wires up out o f the way so that you can walk un -

Photo 5: Thebusinessendof anelevatedguyanchor made fromahuskyI-beam.Note thebackguyon the rightforaddedstrength.

der or mow aro und the m. A big (six-inch o r mo re) ste el I-b eam is one way to go. I' ve seen railroad ties used as elevated ground ancho rs and these are de finitely ind ustrial strength. A good rule-o fthu mb is to have 60% of the anchor above ground and 40% below. D on't fo rget that wit h a six foot elevated anc hor you've got a six foo t moment ar m also. T he ben ding moment force is a result of force times length, so the forc e can quickly become very large. If you are co ntemplating doing this, have an engineer take a look at it o r have them design it. T hat sho uld keep yo u out of trouble. I' ve seen big pip es used as elevated guy anchor s but th ey are mu ch weake r th an I-b eam types - they just don 't have the rigidity in the planes necessary for maximum stre ngth. If you're go ing to use a

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pipe, or tall l -beam , you may want to back-guy it. Filling a pip e guy anchor with co ncrete increases the stre ngth of th e pip e o nly slightly. If you feel better by filling th e pipe with concrete, go ahead but rem ember th at in this case th e added str ength is prim arily p sychological. T he best material for an elevated guy anchor is an I-b eam because it pro vides stiffness in a co uple of planes whe re a rou nd pipe does not. An anchoring technique commonl y used by utility co mpanies is the screw ear th ancho r. R O HN o ffers a 5/ 8" X 4' screw anchor bu t it is only inte nded for temporary ins tallations as it has only 2500 pounds of holding power. Larger ones are available but you have to be able to auge r th em into the gro und. Again, do what th e manu facturer says and put in the specified anchors.

Torque arms Attaching the guy wires to the tower can be done in several ways. The sim plest, bu t not reco m me nded, is to simply put the Pre formed grip aro und th e leg. A better method , but still not recommended, is to use a big shackle with the Preformed grip and thim ble hoo ked sha ckled around the leg. The best parts to use are what th e manufacturer provides. R O H N, for instance, has a guy bracket assembly th at uses medium sized ova l rings between the br acke t and the end of the guy wire. These brackets also add torsion al rigidity to the tower structure. The R O H gu y br acke t historically had steel bars approximately twe lve-inches lo ng; these were referred to as " to rque arms" because th ey supposedly provided additional tor sional rigidity to th e tower. When R OH N incorporated a later EIA/TIA- 222 revisio n into their tower designs, they red esigned the guy brackets to what is available now and ph ased o ut the old torque arms. H am s had be en using these to rque ar ms for years and couldn't be lieve th at R O HN was no lon ger going to sell th em . It seem s that th e old tor qu e arms didn't m eet the new E IA/ TIA -222 spe c and in fact didn't really provide much in th e way of additio nal to rsion resistanc e. What they did do was to dec rease th e twisting of the tower while it was being climb ed . After much pro testing fro m th e field, R O H N starte d offering th em again . If you've got so me o f th e old torque arms, go ahead and use them; the new o nes are just an improv ed design. 1

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Star brackets For really big antenna arrays th at gene rat e large amounts of torque to a tower whe n the wind is blowing, you may want to use a guy fixture called a star bracket or to rqu e ar m stab ilizer. T hese devices are somewhat larger tha n the torque ar ms me ntioned previously b ut th ey also h ave two guy wires attached to each point instead of one. Each of the two gu y wires goes to a different guy anchor and th is arrangement practically eliminates any applied torque to the tower. T his approach is commonly used on guyed towers that have microwave dishes on the m that can't move in the wind. Your 75meter beam tower should have these as well.

12 SAFETY AND SAFETY EQUIPMENT Climbing and working on tow ers is potentially dangero us. Safety and safety equipment are the keys to th e safe and reliable installation, mai nt ena nce and enjoy ment of your tower and ant enna syste m.

OSHA O SH A is the Occupa tio n Safety and Health Age nc y of the Federal G overnment that set s minimum safety standa rds for wo rkers. E ach state has an age ncy that is res po ns ible fo r enfo rcing the O SHA regul ations in that state. In additio n, your state agency may have stricter regulations than O SHA; OS H A regulations are just the minimum requ irements. Washington State laws exceed OSHA reg ulations in man y case s; as a result th ey have an excellent safety record. T he key wo rd he re is occu pati on. If yo u are getting paid or paying someone to do tower work, you or they must comply with th e fede ral and sta te regulatio ns. If you are simply working on your own system, or so meone else's wit hout pay, then you don't fall under the O SH A / sta te laws. But you sho uld still ob serve th em! You sho uld use only OSHA/state ap proved safety equipme nt an d follow th e

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regulations applicable to your activity. By doing this, you'll be giving your self a large and acceptable safety margin while working.

Safety belts and fall arrest equipment T he m o st importan t pieces of .....,...--..--..,......,......,...,.,= ..... safety equipment arc the Fall Arre st Harne ss (FAH) and th e accompanying lanyards. The FAH is the part that you wear and that the lanyards attach to. The FAH has leg loops and suspenders to help spread the fall force s ove r more of your body and ha s the ability to catch you in a natural position with your arms and legs hanging be low you where you're able to breath normally. There are 2 or more lanyards. One is the positio ning lanyard. T hat is, it holds you in wo rking position and attac hes to Photo 1: The well-dressed the Dclimber. Note the positioning nng s at lanyard on theleftwaist D-ring your waist. and theend ofthe fallarrest lanT he y can yard on theright D-ring. be ad justable or fixed and are made from different materials such as nylon rope, steel chain or special synthetic materials. An adju stable positioning lanyard will adjust to almost any situati on whereas a fixed-length one is typically either too long or too short. T he rope type is the least expensive version. By the way leather safety equipment was outlawed some years ago by OSHA so please don't use any ofit. This includes Photo 2: Rearview ofclimber. the old fashioned safety belt that was used The fall arrest lanyard is connected to the D-ring between for years but offers no fall arrest capability. If you drop down off while weartheshoulder blades.

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ing a safety belt, your bo dy weight can cau se it to rise up your waist to your ribcage where it will immobilize yo ur diaphragm and you'll suffoc ate . On th e oth er hand you can use your safety belt for positioning when it's used ove r and in conjunction with Photo3:Aropepositioning lanyard on theleftand anadjustableversionon theright. They both use yo ur FAH . Ju st d on 't double locking snap-hookson theends. depend on it to catch yo u in case o f a fall. The other lanyard is the fall arrest lanyard and attaches to a Dring between your shoulder blad es. The other end attaches to the tower abo ve your work positio n and catc hes you in case of a fall. T he simplest is a 6' rope lanyard which is inexpensive but doesn't offer any shock absorption. There are also sho ck absorbing varietie s which typically have bar-tacked stitches that pull apart under force and decel era te you. Don't cut corners o n buyin g or using safety equipme nt ; you bet yo ur life o n it eve ry time you use it!

Climbing the tower OSHA rules and goo d common sense say you sh ou ld be attach ed to the tower 100% o f the time. You can do th is several ways. One is to attach the fall arr est lanyard above yo u and climb up to it. Use your positi oning lan yard to hold yo u whi le you detach it and mo ve it up again. Rep eat as nec essary. An alterna tive is to use 2 fall arr est lanyard s. This way you can leapfrog th em up the tower. What you use and how you use it is up to you. As lo ng as you've go t th e right safety equipme nt and follow th e ba sic rules yo u wo n't have any problem s.

Safety climb systems Most commercial to wers have a safety climb system that is typically a 3/ 8" steel cable that run s from the top to th e bottom of

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the tower and the climber uses a special trolley that attaches to the cab le from the FAH. The trolley will slide up freely but will clamp the safet y cab le if weight is put on it, thus preventing you from sliding down the cable and tower. T hey are rare on amateur towers but are worth co nsi deri ng.

Mountain climbing harnesses Some amateurs feel that mountain climbing harnesses offer a less-expen sive option for a safety belt. The first problem with using a mountain climbing harness is that most of them req uire yo u to tie the harness directly to a rope or to a carabiner. I wouldn't trust most ham s to tie a figure 8 to attach themselves to anything. You co uld use a lo cking carabiner as an attac hment point but it is another piece of hardware that could fail or open up at an inconvenient time . Second, there are no D-rings to attach any sort of positioning lan yard to; the only thing you have is that one carabiner that connects the loop s in the front. T he n ylon loop that is on the front of the climbing harness is only designed to position the leg loops and is intended to be used only with a climbing rope or carabiner, not the metal snaps of your lan yard that you frequently snap on and off. Climbing belts are designed to be used onl y with climbing ropes and hardware, not with tower tools or equ ipment. They also don't have any provisions for convenient attachment of too l or bolt bags. The final problems are that a mountain climbing harness ma y be des igned for a force of only 1,000 pounds while OS H A fall arrest gear must be de signed for 5,000 pounds of strength, and the mountain clim bing harness has no fall arrest capability. Although th e main advantage of a mountain climbing harness is low cost, it does have its limitations for tower work and I cannot recommend it. Us e only the tools designed specifically for the job and you can 't go wro ng.

Safety equipment suppliers Chances are you've got a safety store in yo ur area . They have some safety equipment and acces sories that yo u can use but yo ur best bet is to search the internet for what you need since tower climbing equipment is not very common. One vendor is Champion Rad io Produc ts (www.championradio.com) that is owned by the author

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and spec ializes in tower related products. Vendors such as Klein, Petzl, DBl-Sala and o thers all provide OS HA approv ed safety equipment . They tend to sell the mor e expen sive products bu t th ey're pre ferre d by profe ssionals who wear and work in them all day. T hese companies will have m any o ther goodies including canvas bu ckets, tool pouches and o ther hardware . Plan on spending $150 and up for a new FAH and lanyard . Just loo k at it as inexp ensive life insurance.

Boots Boots sho uld be leath er with a steel or fiberglass shank. Diagonal bracing o n ROHN 25G is on ly 5/ 16" rod - spending all day standing on that small step will take a toll on your feet. T he stiff sha nk will sup po rt your weight and protect yo ur feet; tennis shoe s will not. Leath er boots are mand ator y on towers like Rohn BX that have sharp X-cro ss braces. Your feet are always o n a slant and th e tower is a real meat grinder o n your feet .

Hard hats The hard hat is highly reco mmended. Ju st m ake sure they are Photo 4:Ourclimberonthetower. His OS HA approved and th at you and positioninglanyard isattached tothe yo ur crew wear them. As you'll be tower and the fall arrest lanyard is looking up and down a lot while hooked tothetower above him. wea ring yo ur hard hat, a chin strap is essential to keep it from falling off. Look for th e ANSI or OSHA label o n the hard hat; th at sho uld be the minimum safety complianc e for your helme t.

Safety goggles Approved safety goggles sho uld be worn to prevent eye injury. Look for AN SI or O SHA approval.

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Gloves If you do a lot of tower work, your hands will take a beating. G loves are esse ntial and I like to keep several spare pairs for ground crew m em bers who show up without the m . Cotton gloves are fine fo r garde ning but not for tower work; the y do n't provide enough frictio n for clim bing or wo rking with a haul rope. Leathe r gloves are the only kind to use; either full leather or leather-palm ed are fine . T he softer th e gloves the m ore useful they'll be. Stiff leather construction gloves are fine for the ground crew but I prefer the pigskin and other so ft leathers because you can thread a nut or do just about an y othe r delicate job wit h these gloves on.

The mental game One of the most important aspects of safety is having th e knowledge and aware ness that will ena ble you to do a job safely and efficiently. You m ust have th e m ental abilit y to clim b and work at altitude while constantly ret hinking all connections, techniques and safety factors. Climbing and working on towers is 90% mental. Mental preparedness is somet hing that must be learned. This is an occasion where there is no substitute for experience. W he n it comes to tower climbing, m y experienc e has been that only a small percentage of people will clim b an d work at altitude. The biggest obstacle for anyone is making the mental adju stment. Properly installed towers are inh erently safe and accide nts are relatively rare . The only thing stopping most people is their own mind and attitude. Would yo u have any trouble standing on a 24" by 24 " piece of one-inc h plywood on the ground? Of course not. Could you stand on that same fo ur square foot platform 100 feet in the air? The only difference is in your mind. I kn ow that it's easier said than done bu t you must make the mental ad justment if you are go ing to do any tower work. About thirty years ago I got invo lved in mountain climbing in Washington state. One of the most important lessons I learn ed, and that is directly applicab le to tower clim bing is that when you climb, you have four points of attachment and security-two hands and two feet . When clim bing, mo ve only o ne point at a tim e. T hat leaves you wit h three points of contact an d a wide ma rgin of safety if you

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eve r need it. This is in addition to having your fall-arrest lanyard connected at all times . Another recommen ded techniq ue is to always do everythi ng the same way every tim e. T hat is, always wear your positioning lanyard o n the same D -r ing and always connect it in the same way. Alwa ys look at yo ur belt D -r ing whi le clipping in with yo ur sa fety strap. T his way yo u'll always co nfir m that you 're belted in. There is a sto ry of a fello w who went to work for a lo cal cable company and went o ut on his first line job. After he got up the po le, he threw hi s be lt around and clipped in . Hearing the reassuring click of his safety belt, he leaned back, on ly to find th at he'd clipped into hi s screwd river! He didn't fall but was so shaken that it turned out to be hi s first and last day on the job. D on't let that hap p en to you . Always loo k!

Ch e ck yo ur safety equipment before ea ch use You should also check your safe ty equip ment every time before you use it. In spect it for any nick s or cuts to your belt and safety strap. Professional tower workers are required to chec k their safety eq uipment every day.

Inclement weather Tower work is the easiest whe n the weather is nice and the sun is shining. Unfortuna tely, that doe sn't always coincide with your constru ction sched ule or repair priority. Fo r raising tower section s or antennas, a relatively windles s day is pr eferred. Profe ssional climbers usually do the ir tric kiest lifts first thing in th e morning when the chance o f wind is th e least. This'll work fo r ham wo rk too. Don't push on in marginal conditions; you may wind up doing more harm th an good. Obviou sly you don't ever want to climb during a lightning storm. As far as rain goes, unless it's coming in ho rizon tally it's mo re o f a nuis ance . For ham towers, you'll always be belted in and yo u won't be walking acros s any rain slicked sur faces, so working in the rain is possible. J ust dr ess with good rain gear and you 'll be able to still get some work do ne. Don't he sitate to call off your project, though . If you're not sure if the weather is good enough , it prob ably isn't.

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More tips 1. Don't climb with anything in your hand s; attach it to your safety belt if you must climb with it or ha ve yo ur ground crew sen d it up to yo u in a bucket. 2. Don't put any hardware in your mouth ; not only does it taste funny but also you could swallow something. 3. Remove any rings and/or neck chains; they can get hoo ked on things. 4. Be on the loo kout fo r bees, wasps and th eir nests; there aren't too m an y bigger surprises whe n you're clim bing a to wer (imagine a nest big enough to engulf a portion of 25G!) . If you do run into a hornet, wasp or other stinging insect, use Ado lph's Mea t Tenderizer on the sting. T here is an enzyme in it that'll cut the pain within a minute or two. I always have a bottle with me just in case. 5. Don't climb whe n tired; th at's when most accidents occur. 6. Don't try to lift anyt hing by yourself; one person on a tower has very little leverage or strength. Let the ground crew use their strength; save yours for whe n you really need it or yo u'll quickly run o ut of arm strength . 7. If something doesn't work one way, re-rig, then try again .

13 TOWER CLIMBER AND GROUND CREW T he re are three im portant factors fo r the success of any tower work; attitude, knowledge an d com mu nicatio n. An at titude emphas izing safety will keep you from taking unnece ssar y risks. It m eans doing everything in a manner that is safe fo r all involved. It also m eans knowing when to back away fro m so me thing in which you 're not fully confident. Knowledge is gained not only fro m expe rience but also fro m research such as reading th is boo k and talking with folks who have do ne it before. Don't reinvent the whee l; use all available resources to plan an d successfully exec ute your project. The best reso urce around for tower related topics is TowerTalk, th e tower and H F ante nna co ns tructio n internet reflector. There are almost 2000 members an d it is a source of an swers to just abo ut any rel at ed q uestio n . To s u bs c ri be , se n d an email to to wertalkreq uest@ co ntesting.co m wit h in th e subjec t an d you' ll be all set. T he re are also Tower Talk archives at www.co ntesting.co m . Communication is more than just agreeing on a simple x frequ ency for your handhelds. Everyo ne on the tower and on the ground mu st be

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kept fully informed at all times. A tower crew that has previously worked togeth er likely has their communication s protocols and signals worked out, whereas an inexperienced gro up of buddies and / or vo luntee rs mu st be directed in their assignme nts at each step along the way if they are going to work togeth er safely and efficiently. Remember that an y tower project will take longer th an expected; usually by a factor of two or three. D on't try to rush an ything to get th e p roject finished; this will only decrease yo ur margin s of safety and greatly increase th e chance th at you'll end up doin g things more than o nce . Even experienced crews run int o delays such as missing tools, inco rrect size hardware, etc.

Pre -work meeting O n proj ect day, the first thing you sho uld do is have a session with th e entire crew and go over what is going to be accomplish ed, and the order and manner in which it is going to be done. You sho uld also cover all safety issues, commands and eq uipment related to th e job . Point o ut any hazards in the wor k area such as po wer lines, etc. Ex plain an y special ized equipme nt o r tools, including cara biners and slings, come-alongs, hoisting gri ps, etc. If you're goi ng to be using a come-along, be sure tha t so meone knows how to work it. Fo r so me reason, success ful co me -along ope ratio n elud es the firsttim e user, so spe nd so me tim e explaining and learn ing how to use it. Point o ut wh ere a phon e is and any phone numbers th at may be need ed in an em ergenc y. You sho uld also discu ss and und erstand what to do in an em ergency situation . For min or emerge ncies, knowing whe re the closest medical facility is will be valuable. Since just abo ut everyone will have a cellph on e, calling 911 wo n't pr esent any pr oblems for bigger eme rgencies. The problem is th at man y emergency services professionals have not been trained for high angle rescue such as lowering som eo ne off o f a tower so you're pro bably go ing to be on your own at least initially. Search and rescue crews are used to working with ropes and other hardware for extrication s so hopefully your 911 ope rator will be able to put you in touch with them. Physical trau ma can set in quickly even with a Fall Arrest Harness so quick action is vital. Let your crew know that th ey mu st not be standing around the bottom of the tower unless the y mu st specifically be there. This is the

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danger zone for dropped tools and hardware. RULE # 1. T h e guy up on the tower is in charge. Do what he tells you. Don't do what he doesn't tell you. Being on the gro und crew is usua lly pretty boring, but don't take it up on yo urself to do anything that would have any impact up on the tower. \'V'ith very few exceptions, don't do an ything un less directed to. If you're not sure about something, ask the guy o n the tow er. RULE # 2. When talking to the tower crew, look up at them and talk in a loud, concise voice. Although it may be still and qui et where you are on the gr ound, the ambie nt noise level on th e towe r is always significantly higher. The three main sources of noise at altitude are do gs, traffic and wind. Co mbine th ose with being 50 to 150 feet up in the air and you h ave m ajor communicati on o b sta cles. I've found VHF / UH F handhelds to be useful. Stan Griffiths, W7NI, suggests using the inexpens ive VOX-ope rated headsets th at run less than a watt o n the 47MHz band. Make sure you have good communications between the g ro und and the tower. And mak e sure that all batteries are fully ch arged ! Commands H ere are th e commands that I use. I make certain that everyone understands each of th e commands and that they all use th e same ones . All o f th e command s refer to th e 'load' (antenna, tower section, etc.) and are applied to the 'haul rope' (the line to which the load is attached). "Tension" tells your crew to put tension on the line, to take up any slack. O nce yo u have so me Tension, you can move th e load with "Up" o r "Down" commands. "Slack" means giving the load some slack. "All slack" m ean s th e ground crew may g radually and gentlv release their grip on the load. "Stop" is obv ious and "Stand by" ind icates that the y should

maintain their assignme nt while awaiting the ne xt co m ma nd. Again , th e guy o n the tower is in ch arge; don't do anything witho ut his instruction . If yo u drop so me thing, alert the grou nd crew imm edi ately. Yell "Look out below! or "Headache!" so that they ca n get o ut of th e way of th e wa yward bolt, nut or tool. Th eir hardhat s o nly p ro vide minimal p ro tection aga in st this occ ur ren ce. Co nce ntrate o n not d ropping an ything. Dropped item s are not o nly dan gerou s but it also m ean s that yo u' re doi ng slo p py work . A good rigger might only d rop so mething o nce o r twice a yea ror eve n les s. There are also several common hand signals that you may want to use. Simple ones for up, down and stop can be useful, particularly in high-noise situations.Ju st make certain everyone know s wha t they are.

RULE #3. Really communicate. I insist that my gro und crew keeps me really informed. If I lower so mething to the gro und, I want the gro und crew to tell me that it's "On the ground". If I'm waiting for th em to do so me thing, 1wa nt them to tell me wh en it's "Ready" or "Just a minute". Mo re th an o nce I' ve been waiting and waiting for so me thing that was rea dy, but th e ground crew didn't tell me so we bo th stood there for som e tim e un til I asked fo r a status rep o rt. It's much easier to communicate an d also mu ch mo re efficient.

Take care of your crew If you've man aged to talk a bunch o f your buddies or radio club members into helping yo u, by all means roll o ut th e red carpet for them . They're giving up th eir tim e to help you and they deserve it. Make an effo rt to provid e lots o f water or iced tea and by all me an s feed everybody a nice lunch. (A six-pack or keg ma y be welco me , but only after all tower wo rk is finished.) They may eve n co me back sometime in the future to help yo u again!

Crew size For small antenna job s, two people (one on the tower and one o n th e ground) are usually enough. Even erecting 25G (40 pounds

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per sectio n) can be acco mplishe d with two people, bu t this is a case where a third person to handle th e tag line is real handy. For 45G, you'll want to have two people o n th e haul ro pe as these sections weigh 70 pounds each , and a section with guy brackets is close to 100 pounds. Commercial riggers commonly use so me type of winch or windlass to haul up heavy load s. Fo r working with large ante nnas, such as 40-meter beams, two people o n the tower along wit h one or two tag line folk s plu s two to four o n the haul rope means that you' ll need a large crew:

The gu y on the tower If you're the guy on th e tower, I' m assuming th at the reason that you're up there is because you know what you're doi ng. Before you climb the tower, do wha t airp lane pilots traditionally do; walk aro und it and m ake a thorough visual inspec tion. Look at the base for cracked or rusted legs or missing hardware. Go out to the anchors to check the turnbuckles, clamp s and other hardware. Look for bee or wasp nests. Never assume that any tower is safe to climb, always inspect it thoroughly before you take that first step. \X1henever I'm working wit h someone on a tower, before we do any ma neuver, I always explain how we' re going to do it and the sequence that we're going to use . T his way, they will understand the process and will do the right thing at the right time , hopefully. This is particularly imp o rtant if you're up there with someone that you've never worked with befo re. Sometimes you both assu me tha t th e other guy is going to do so mething obvious that needs doing and then neither of you does it. This can be da ngerous. Go over everythi ng. If the person has little experience, he'll get an ed ucation whi le he's at it. It'll also make it easier the next time you work together. Pu t your tools either in your buc ket o r tool bags on your belt. Try to avoid putting anything on a flat surface such as the rotator plate or thrust bea ring plate ; they can roll off. Avoid using ac-powered tools on the tower. Battery powered tools are safer; you can bu y, borrow or rent them . If you mu st use ac-powered tools, make certain they are insulated and that the extension cord s are suitable. Zi p co rd exten sions are tacky and dangerou s. Make certain your ground crew knows where to disconnect the extension cords, and/or where th e br eaker box is loc ated .

14 TOOLBOX Any job anywhere is easier and safer if yo u've go t the right tools and tower work is no exception. If you are a weekend me chanic o r handyman, you've probably already go t most of what you need; all you need to do is add a few specialized items and you're good to go. If, on the othe r hand, all you have is a hammer, pair of pliers and a screwdriver, you'll need to make a trip or two to the too l store before you can really do anything. When my son reached the age where he was using (and losing) my tools, I went to S EARS and bought him a basic set of Crqftsman tool s and a toolbox for less than $100 That's probably abo ut right for a minimum set of wrenches, sockets, etc. O nce you have them, you'll be all set whenever any of your buddies want help on their tower. There's nothing worse than rollin g up to spend a day working and your buddy can't supply an y really use ful tools. Be prepared; yo u'll never go wrong.

Basic toolbox Most ama teur tower and an tenna work can be done with a

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minimum of h andto ol s. N ut sizes o f 7/ 16", liz " an d 9/ 16" are yo u 'll usu ally ne ed.

Essential tools 1 set of com b in ation wrenches: 7/ 16 " , liz" and 9/ 16" 1 se t of so ckets 3 / 8 " drive 1 each de ep sockets: 7/16 ", 1/2" , 9/ 16" 1 each screwd rivers (blade and Phillips) 2 ad jus tab le pliers or Cb annellocks 1 di agonal cutters (dikes) 1 razor blade utility knife 2 pulleys 1 driftpin or centering punch (for lining up to wer se ctions) 1 hammer (1 have a couple of feet of line on mine so it'll ho ok onto my belt or a tower member) 3 each ad justa ble (Crescent) wrenches-small, medium, and large 1 bubble level 6 carabiners 6 one-inch nylon web bin g slings - 2' long 250' rope (or more - this is enough for working on a 100' to wer) 1 canvas bucket (for parts hauling and st orag e) 1 Loos PT-2 g uy wire tensioner 1 set nutdrivers 1 (or more) come-a long or h an d cable wi nch 1 (or m ore) cable grips 1 ci rcular saw with aggregate blade or hand grinder (fo r cutting m etal, in cl ud ing guywires) 1 tag line ( If." is fin e -yo u chos e the size an d length) 1 cordl ess drill, w ith assorted b its an d socket driver 1 set drill bits including step -drill, e .g. Uni-Bit 1 an tenn a analyzer, e.g. M FJ -269 1 gi npole 1 so ldering gun and solder

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Come-alongs A come-along, or hand cable winch, is very useful for pulling tower sections together , tig h ten ing tram lines and tensioning guy wires. You'll prob ably find more uses for it. Cheap ones are fifteen to twen ty dollars and are fine for occasional use. T he best ones for tower wo rk are the ones that have spring-loaded safety latches over the end of the hooks. Learn how to work it beca use you'll have to explain it to other people since comealong use eludes the first time user.

Cable grips Two tools tha t go together are the Photo 1:Canvas tower bucket. come- along and th e cable grip. A cable gr ip is a springloaded device th at slides up th e guy wire but clamps down whe n you put tension o n it. Klein is the primary supplier o f them and th ey come in lo ts o f sizes and design s for use with vario us materials. Fo r Photo 2:Klein Chicago cable grip on leftand amateu r use, th e Klein 1613- Klein Heven'sgrlponrlght. 40 is for 3/ 16" and W' E HS guy ma ter ial wh ich happen s to be what 90% of amateur towers use . \X!hen erecting a tower I carry 3 of them along with 3 come-alongs so that I can put initial tens ion on all 3 guy wires at the same time.

Steel cutter Event ually you' ll need to cut so me stee l. G uy wires, rebar, pipe, tu bing, tower sections, etc. are all

Photo3:Drift-pinortaperpunch and ratchet box-end ratchetwrench.

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materials that can be cut easily with th e right tool. I started out using a circu lar saw with a steel cutting agg regate blad e. It was cumberso me and heavy bu t it wo rked. And since the steel cutting blad es are cheap, it was an easy way to go. But the best cutting tool is a 4-1/2" hand, or angle gri nder. Get one-eighth inch steel cutting blades fo r all your cutting job s. Yo u can also get grinding wheels, wire br ush es and other accessories for it.

Cordless drill Yo u' ll use this all the time, and it's just not for drilling. Other tasks you can use it for are tighte ning nuts, ho se clam p s and o the r hard ware and wire bru sh ing. While a typical household drill is oka y for oc casional small jobs, it's worth th e investment to ge t o ne with higher vo ltage. The minimum vo ltage for the drill

Photo 4: Drill socket driverfor 3/8" socketsand 5/16" nut setterfor hoseclamps.

sho uld be 12 vo lts. Hi gher vo ltages like 18 and eve n 36 vo lts are currently available. And be sure to have a spare battery. My Milwaukee co rd less dr ill even has a half-in ch ch uck - a very desirable feature!

Drill bits You'll obviously need a set of dr ill bits. Other very handy item s are step -drill bits (also known as Unibits), so cket d rivers and single-sized nut drivers. Eve r tried to expand an existing hole? You take a bigger size drill bit and start drilling. Un fortu nately many time s th e hol e will ovalize as you try to m ake the hole bigger. T he

Photo 5: Step drill bits. The one on theleftgoes from 1/8" to "h".The one on theright goes from 3/16" to 7/8".

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solution is a step-drill, or Unibit. Most have a chisel tip to get you started and then you just keep drilling until you get the desired sized hole . E asy. And it's perfectly round ever y time. You'll wonder how you ever lived without them!

Antenna analyzer T hese fabulous devices have made working on antennas easier than ever before. I have used an M FJ-259 for years and prefer it since you can sweep the frequency spe ctru m while you loo k fo r a dip .

Ginpole The purpose of a ginpole is to provide a pick-point up high enough so that you can lift an object abo ve th e top of the tower, th en drop it into place. Typ ical ginpole loads would be tower section s (10 feet long) and masts (6 to 22 feet long). You want to pick up the se loads just abo ve their mid or balance point, so that the y will come up in the correct upri ght position for installation. T he ROHN ginpole is twelve feet long, just righ t fo r lifting a ten-foot tower section. For twenty foot ma sts, a twelve-foot ginp ole is very marginal becaus e the re is barely ten feet o f working length available fro m th e ginpole and a big m ast will probab ly exceed the rating for th e Ro hn ginpo le which is rated for a 45 G section th at weighs 70 pou nd s. Drawing 1: Ginpole,drawLarge, he avy-duty masts require special ingbased onRohn EF2545. handling; th ere are several options for th eir in stallation. (5ee chapter 18, T ower Erection ') For ROHN 25G and 45G, a ROHN ginpole will be quite sufficien t. Often these can be bo rro wed or rented from a local radio store or club so you don't ne cessarily have to own one . For ROHN BX, Trylon Titan or tower s from other manufacturers that have angle legs, a different ginpo le is needed. A uni versal ginpole can be fab ri-

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99

cated utilizing a 12-foot to 15-foot piece of 6061-T6 aluminum pipe, o r equivalent (2.0" OD, 1/8" wall is probably sufficient). If the ginpo le doesn't have the correct leg mounting fixtu re, you can sim ply lash th e ginpole to a leg with some short-lines- this will suffice for m ost ham towers. Take care to insur e th at the ginpo le wo n't slip down the leg. I use a sling with two carabin ers o n it - one carabin er hook s the bottom of the ginpole and th e sling attaches to a convenient tower member with th e other carabiner.

Pulleys Pulleys are used constan tly in tower and ante nna projects. There's always one at the to p o f th e tower for the haul rop e that willbe used to bring up parts, equipment or h ard ware. Steel pulleys are relatively inexpensive and pl entiful. Their bi gge st drawb ack for amateur p roj ec ts is weight; a sma ll o ne weighs two or more p ounds. Climbing w ith a few o f th em o n your belt turns int o wo r k. The y cost $25 to $35, and can be found in m an y hardware stores or rigging sho ps. T he best pulleys I' ve found are m ade from nylon and are used by util-

Photo 6: Closed snatchblockpulleys.

Photo 7:Open snatch block pulleys.

it)' company line crews. Their nonconducting advantage for high voltage work is obvious, but th ey are just wo nderful for ama teur proj ects and available from Ch ampion Radio Products. Two important things to consider wh en shopping for pulleys are shea ve size and sheave

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clearance. A sheave is a wheel with a groove in it, the wheel in the pulley. A two- inch diam eter sheave is the minimum size you should consider. Anyt hing smaller adds more friction to the effort of your hau l rope, etc. A three-inch or four-inch pulley is even better. The kind of pulley you want is called a snatch-block. With a snatch-block, th e to p of the pu lley opens up so that you can put the pu lley anywhere on the rope. You want a jam -pro of pu lley that has zero clearance between the sheave and the pulley body. If there is any way for your hau l rope or cable to jump the pu lley and get jamm ed, it almost certainly will.

15 CARABINERS AND SLINGS O ne o f the more valuable lessons I learned from my mountain climbing days was th e value and incre dible usefulness o f two pieces of climbing hard ware; carabiners and nylon webbing slings.

Carabiners and snap-links Carabiners are steel or aluminum snap-links with spring load ed ga tes ; the y are invaluable for do zen s of tower wo rk tasks. For exam ple, put one at the end of yo ur haul rope, then attach it to rotator s, parts bucket or virtua lly anything else w h ic h needs to b e raised o r lower ed . A cara- Photo 1:Typicalcarabiners and snaplink. Carabineronleftis biner can be a open forillustration purposes only. Secondcarabiner isin third hand o n nonnal closed position. Third carabiner hasautomatic spring th e tower; you gatelock. Snaplink on right issteel variety.

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can clip a carabiner to almost anyt hing with a ru ng o r diagonal brace. You can instantly hang a pulley fro m a tower rung. Any place where you wo uld use a shackle, you can use a carabiner. A shackle has two piece s, either of which will be d ropped at an inopportune tim e whe reas a carabiner is one piece and attaches in a flash. I carry twelve to fifteen carabiners o n my belt at all times and I'm ama zed at the nu mber of times I've used all of them.

Carabiner ratings Mountain climbing carabiners used to be rated fo r br eaking strength; a typical ratin g was 2000 kilogram s (4400 pounds) or m ore. T he probl em was that this was a static load condition and did n't really reflect th eir use in dynamic climbing o r falling situation s. Carabiners are now rated in kiloN ewtons (kN); th is re flects a more realistic dynamic load stress . (O ne kN equals 225 pounds o f force.) Curren t ratings for mountain climbing carabiners are typically in th e 6 to 10 kN (1350-2250 pou nds of force) range with the gate open and 18-2 5 kN (4050-5625 pounds of for ce) with th e gate closed. A word of cautio n: mountain clim bi ng carab iners are not OS HA approved. As they are for p rivate use, they do n't have to be co mpliant. And in the case o f tower construction th ey're just going to be used for loads an yway. O SHA approve d carabiners are also available, the se are called safety hook s and can be pu rchased fro m your safety equipment supp lier. OS HA approved devices are usually made o ut o f steel, ins tead o f the aluminum used in m ountain climbing carabiners, and generally are th e locking type. A typical rating fo r a co m mercial carabiner is 40kN (9,000 pounds o f fo rce), a mu ch higher rating than mountain climbing types. On th e o ther hand , m ountain climbers have been tru sting th eir lives to carabiners for almost fifty years and the current versions are mad e out of sophisticated materi als and thoroughly tested. You may feel th at they are safe for yo u to use also. They typica lly cos t $6 to $10 and will last for years with little or no maintenance. But if and whe n th e gate no longer opens and clos es smoothly, the y sho uld be discard ed .

Slings T he othe r indi spensable tool is the loop sling made fro m o neinch nylon tubular webbing. T he sewn webbing loop s can be wrapped

i s -C A RA BI N ERS AN D SLINGS

103

aro und large o r irregu larly shaped ob jects. They have around the same breaking stre ngth as cara biners (approximately 4000 pound s, or 18.1 kN force) and are very handy for ama teur app lications and loads. Wrapping o ne around a tower ru ng o r leg provides a conve nient place to hang tools, part s o r a pulley. Like carabiners the y are not OSHA approved but they're used for mountain climbing protection everyday so if you don't feel that o ne-inch webbing slings are appropriate for yo u, you can purchase OSHA approved slings from yo ur safety equ ipment supplier. Like carabiners, th ese are no t typica lly used in tower work for fall protecti on - the y'r e u sed fo r lo a d ha uli ng. The OSHA ap proved ones are typ ically made from yellow nylon and are certified for a given strength factor. They are availPhoto2: Nylonsling on tophasaneye ineach end. Bottom able in different sling isendless loop. sizes, and configurations from having loops at each end to being a continuo us loop like one -inch m o untain climb ing slings. Alth ou gh they are more expe nsive than the one-inch webbing slings , the y will last for years and are an excellent rigging and safety investment. I personall y use the lighter mountain climbing type s for eve rything except big load s like a tower.

Lifting loads wi th slings Slings are typically used in one of three rigging co nfigu rations: 1. Stra ight pull - A simp le direct vertical attachment. 2. Cho ker - \'(frap the sling around the load one o r more times, insuring that you pu ll the loop through itself o n each wrap, cinch it tight, clip it int o a carabiner and pull it up! This is called a choker; the secret to this operation is th at the more ten sion you put on the sling, the tighter it gets. Rem em ber the Chine se finger pu zzle

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whe n you were a kid? T he more you pulled it, the tighte r it got. You co uld only ge t it off whe n you relaxed th e t en si on an d pu sh ed your fing ers together. The same principle is at wo rk h er e and it will simplify your mast raising projects immensely. What system do yo u use if yo u have a heavy ma st to in st all? H ow do yo u attach it to the haul line? Do yo u jury rig som ething? Nylo n slings are invalu abl e for pulling up m asts, fro m sma ll Drawing 1:Three basic hitches. o nes to the 3" x l/ Z " wa ll m onsters. Just rig your slin g as a choker, th en haul away. I've n ever had o ne slip bu t yo u can add a U-cla mp above the sling fo r red unda n t p ro tecti on. A cho ker will wor k in m an y o th er cases where yo u have an irre gular load to haul, not just mast s. Using a sling as a choker will reduce th e lifting capacity of the sling by as mu ch as 30% th ough. 3. Basket - Bas ket hitches distribute a load equally between th e two legs o f a sling. T he greater the angle between th e two legs, the sma ller the capacity of the sling.

Big carabiners and gorilla hooks Larger carab iners are available th at have locking gates; these will give you an add ed degree of safety, particularly if yo u are using th em for yo ur own protection or if you just want to be doubly safe. They're only a couple of dollars more than th e standa rd, non-locking typ es. Also, there are big carabiners available; these are used fo r rescue wo rk and o ther applicatio ns whe re you need a wide r gate open-

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C ARA BI N E RS AN D SLINGS

105

ln g. Th ese ar e so me t i mes call ed go ri lla hooks or reb ar h o o ks an d ar e fo r p e rfe ct large r to w er rung s ( RO H N BX , e t c .) a n d la rg e r lo ad s. Photo 3:Arebar orgorillahook.Themouthwillopen2.5". O SH A compliant device s are offered by your safety equipment supplier, and in so me cases are th e same o nes th at are available from climbing hardware sto res.

U sing carabiners and sling s These devices are revolutionary for tower and ante nna wo rk and they are safer th an most of the alternatives. If you are doing tower and ante nna wo rk, you sho uld be using carabiners and loop slings . And th e beauty is that you can use them for just about anything. Need a spare hand? It's right the re. N eed to hook your ro pe onto something ? N o problem. Try th e carabiners and slings- they'll make your job faster, easier and safer. O ne carabine r/ sling trick I frequently use is to take a two -foot sling and loop it through the fixture of the R O HN gin po le assembly, th en clip both ends with the carabiner. Yo u now have the ability to clip it onto a haul ro pe, clip it onto yo ur safety belt to bring it up to th e next sectio n or you sim ply have so mething to grab onto when you're moving it aro und o r attaching it to a tower leg. T his is invaluable as the re is nothing on the gin po le fixture itself to ho ok anything o n to. H ere are some o the r ways th at you can use carabiners and slings for your tower project: 1. Atta ch a sling to an anchor rod as an att achment point for one end of the co m e- along fo r pullin g guywlres. 2. Clip a carabine r o nto a rung at the bottom of th e tower, then atta ch yo ur haul ro pe sna tch bloc k

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pulley to it. 3. Use a sling to ho ist each tower section and to keep it vertical. 4. Pu t a loop through your level, the n clip it to yo ur belt with a carabiner. 5. Always have a cara biner clipped into the bowline at the end o f your hau l rop e and tag line for quick load attachme nt. 6. Clip a carabiner into the U-bo lt o n your rotator to haul it up.

16 ROPES, KNOTS AND ROP E MANAGEMENT If yo u are go ing to do tower and anten na work, you' ll be using ropes. The most common uses are for hau l rope, tag lines and temporary guys.

Manila Mani la is still the best known natural fiber rope. At one time it was th e best rope available but it is steadily losing gro und to the synt hetic fiber ropes. Manila mu st be handled and stored with car e as an y dampness will cau se it to ro t and, o f course, m aterially damage its effectiveness and safety.

Polypropylene P ol yprop ylene that have exte nsive and are unaffected cal s. Pol ypropylene knot we ll.

is u sed to make lightwei ght, stro ng r opes use s. T hey float on w ater, are rot-proof b y water, o il, g as o lin e and mo st chem ir op e is relativel y sti ff an d do e sn't take a

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Nylon Ny lon is the stronges t fiber ro pe commercially available. Due to its elasticity, nylon ro pes can absorb sudden sho ck load s that wo uld bre ak ro pes of o the r fibers. They have very good resistance to abrasion and will last four to five times lo nger than natural fiber ro pes . Nylon ro pes are rot -proof and are not dam aged by oils, gasoline , grease, marin e growth or most chem icals.

D acro n A dacron ro pe is adv ertised in the ham radio magazines. It comes in three sizes (-'/32",3/16" and 5/16") and its claim to fam e is th at it is UV resistan t. This would be an excellen t candidate for any rope left o utside such as permanent haul ro pes o r wire antenna halyards. Table 1 . Rope Sizes and Safe Working Load Ratings (in pounds) . 3 strand twisted line Nylon

1/4 3/8 1/2 5/8

120 2 15 420 700

180 405 700 1140

. . . . .[B.._ _ 180 405 700 1100

2 10 455 7 10 1050

Table 2 - Rope Sizes and Safe Working Load Ratings (in pounds) . Double braided line I

•

.

Nylon

.

1/4 3/8 1/2 5/8

420 960 1630 2800

I .

•

350 750 1400 2400

Rop e lay All rop e is twisted, or laid; and just abo ut all laid rope is threestrand construction . This laid rop e is what yo u'll find at your local hardware store. An other type o f rop e is known as braid-o n-braid, or kern mantle. T his has a laid co re that is covered with a braided jacket to produce a stro ng, handso me, easy han dling rope. In m ost instances, braid-on-b raid rope is stro nger than twisted rop e of the same material and diameter. It is available in various synthetic fibers. Mari ne supply stores and mountain climbing sto res carry a large variety o f braid-on-braid types as well as a variety o f types and sizes.

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Which rope to use There are severa l fac tors to h elp yo u make an in fo rmed ch oice about whi ch ro pe to buy. First, decide whic h size will suit yo ur needs, based on wo rking load sizes . Mo st ama teur loads ar e less tha n 100 pounds, ve ry rar ely do they get above 25 0 po unds . So a haul rope h avin g a wo rki ng loa d range between 100 and 250 pounds will h andle just ab out anythi ng. Second, ch oose th e typ e an d m at erial of yo ur ro p e. Pol yp ro pylen e rop e is stiffer an d m o re difficult to kno t th an nylon. N ylon and braid- o n-b raid ro pes are so fter and will take a kn ot ve ry eas ily. Th e so fte r rope s also coil more easily and ar e m ore resistant to kin king. Fin ally ch oo se the length th at will be th e m o st useful fo r yo u. I f yo u double th e size o f yo u r typic al tower a n d a d d 25 %, yo u ' ll h av e pl enty. A 100foot to wer t im es tw o give s yo u 200 fee t pl us 50 fe e t (2 5% of 200 ) for a total d esired haul ro pe len gth of 250 feet. I h av en 't men tioned price because you ge nerally get wh at yo u Photo 1:One convenient wayto store your rope. pa y for an d yo u kn o w what your budget will allow. Prices vary from $18 for 600 feet of 1//' po lypropylene to $125 or m ore for 165 feet o f high qu ality kernmantle climbing rope. I carry two lengths of 9/ 16" braid-an-braid for haul ro pes. O ne is ap proximately 175-feet long and can be used on to wers up to 80 feet . The othe r haul rope is aro und 350-fe et long and can be used for tower work up to 165-feet. T he shor ter ro pe is coiled when not in use and the longer o ne is simply fed int o a plastic crate fo r storage. If you feed the rope into the crate properly, the ro pe will feed o ut of the crate without kinking o r kno tting. Make certain th at the ro pe en ds will no t unravel. Most supply stores will cut th e len gth with a h ot kn ife; tha t will do th e be st

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job of sealing the end s. Yo u can do it at home by simply melting the ends with a ligh ter. An alternative is to tightly wrap a few layer s of electrical tape around the ends. Be sur e to tape th e en d s of all yo ur rope s.

Knots O nce you've got your rope, you'll be tying and un tying it do zens, even hundreds, of times. You can do about 98% of your towe r and antenna work with only three knots-and you already kno w one of them. It's all but impossible to use a rope without tying any knots in it, remember th at an y knot will decrease the breaking str ength of the rope-usually 40% or more. Choos e and use th e correct rope and kn ot s for the job , and you should have no problem s.

Overhand knot When yo u tie yo ur shoes, you're using overhand knots. These are tied by making an overhand lo op, then pa ssing the end under and up through the loop and then tightening. A ver y handy use for the overhand knot is wh en you need a loop in the midd le of yo u r rop e. Ju st . "-='. ~~ double the rope Overhand Knot In The Middl e of a Rope o ver for a b o u t two feet, tie an overhand knot and you have an instant loop.

~ ~

The bowline This is perhaps th e mo st useful knot you can know; if yo u're going to be stuck on a desert island and yo u can only take one kn ot with you, this is it. The bo wline form s a loop that will not slip or jam, yet unties easily. It is used for hoisting, joining two ropes and fastening a rope to a ring or cara biner. This is th e " rab bit comes up

16-

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111

through the hol e, around th e tree and back down the hole" knot th at you likely learn ed as a Boy Sco ut. To tie it, form a sma ll loop in the ro pe. Run the end up through the loop, behind th e standing part, then back down through the loop. Pu ll tight . Practice this one unti l you can make it alm ost automatically.

Figure-eight knot Altho ugh the bowlin e is a hand y knot, it isn't foolp ro of; it requires a bit of practice to get it right every time . A simpler knot th at may be used in most situa tio ns in place of a bowline is the figureeight kno t. It is tied just like a doubled ov erhand, excep t that the rope is tw iste d an additional half-turn before the knot is pu lled th rough the loop. It is one o f th e few knots that can be easily Sup 1 Sup 3 untied after holding a severe imp actioad, such as Fi~ure 8 Knot a falling mountain climber. It's only disadvantage for tower wo rk is that it is a ph ysically larger knot, and it takes a bit m ore ro pe than a bowline. Figure-eight or bowline; either knot will serve you well.

The clove hitch O nce yo u've mastered th e bowline and / or the Figure-eight kno t(s), the o ther very useful knot you may wa nt to learn is th e clove hitch. It can be invaluable w he n yo u're wo rk ing with round obj ect s, and it can be put o n or aro und almost any object very quickl y.

Clove Hitch

Truckers' hitch Many time s you're wo rking with a rope and you want to tighten th e rope as much as you can bu t using a ro pe grip and come-along

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Up TIfF TO WE R

just isn't practical or possible. T he ans wer to this problem is to use a truckers' hitch. You simply tie an overhand knot up the rope to give you a loop toward s th e load end, run the end o f the rope PullEt1a t hro ug h a ca rabiner or '--./ shackle at a con venient anch or p oint, put the en d th rough the loop and th en pull b ack to tighten the rope. This technique gives yo u twice th e mechanical advantage of pulling on the single rope and acts as a mini-corne-along to really tighten the rope.

Rope care Inspect your rope periodically and replace it if there is an y visible serious abrasion or damage. Mountain climbers ro utinely replace their ropes after the y sustain a single hard fall, which can cause invisible internal damage; also afte r their ropes are exposed to a season or two of deteriorating ultraviolet sunlight. H ere are some additional tips for using ropes: 1. Be certain your rope size is adequate for the job; don't use a rope that is too small. 2. Dry your rope before sto ring it. N atural fibre (Manila) ro pes will mildew and rot if stored wet. I occasionally put my nylon ropes in th e clothes dr yer for a bit (low heat) when they've become really soaked . 3. Don't store ropes in dire ct sunlight; UV deterioration will significan tly we aken th em . 4. Cut out and discard any badly wo rn or abraded portions of a ro pe; better to have two shorter ropes yo u can tru st than o ne long one that is suspe ct . Heat and/ or tape th e new ends to prevent unraveling. 5. K eep yo ur rope clean. Don't drag it through the mud, nor ov er a rough or gritty sur face. D on't ever step on it, either! 6. Watch for kinks; they can cause permanent damage and

16-

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~IANAGEMENT

113

weakening. 7. Protect ro pe s fro m all ch emi cals such as acids, oils, gasoline, paint s, solvents, etc. 8. Avoid sudde n stra ins; shock loadin g or jerking may cause failure. 9. Avoid overloading. A safe working load for a ro pe is tento twenty-percent of its b reaking stre ng th. 10. Avoid abrasion. If th e ro pe mu st ru n over a towe r leg or any sur face with a sharp edge, protect it with a layer or two of canvas o r o the r such material. 11. Avoid sharp angle ben ds; th ese can g reatly affect the strength o f a rope.

17 G UY WIRES

O ne of the m ost innocuous elements of a tower installation is the gu y wires. Not as aesthetic as tower sec tions, nor as elegant as antennas, guy wires are the hear t of a reliable guyed tower system. Almost any tall amateur tower is going to be guyed. R OHN 25G, 45G and 55G are the most common towers used by ama teurs and the y all need to be guyed. G uy wire failure is no t common, but does happen. O ve rloading is the typical culprit, but sometimes a tree will fall across gu ys; that's also guaranteed to require a call to the insurance company. O ne ob scure failure was an amateur who taped the ground anchor ends of his guys at the turnbuckles. Over the years, the water ran do wn th e guywires and was trapped by the tape. That led to ru sting; since the rusting was hidden by the tape, it couldn't be seen . Eventually all it took was a large windsto rm to snap the rusted windward gu y and the top half of the tower buckled . It's another instance of doi ng something that th e ma nufacturer didn' t tell you to do . A more common failur e is for some critical piece of hardware to break or pull out.

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\,IIRES

115

Guy wire grades Steel guy wire co mes in several different gr ades. R OHN specifications call for E H S (Extra High Streng th) cable exclusively. As you can see by th e chart, this is the strongest steel cable available. Typical 3/ ,,,"steel guy wire spe cifications Common Grade: Utility Gr ade: Siem ens-Martin Grade: High Strength Grade: Stainless Steel Aircraft: E xt ra High Streng th Grade: Pbillystran: HPTG4000

1,540pounds 2,400 pounds 2,550 pounds 2,850 pounds 3,700 pounds 3,990 pounds 4,000 pounds

This ch art shows th e imp ortan ce o f foll owi ng th e tower manufacturer's recommendations fo r th e prop er guy material and stre ngth. Just because yo u bought a reel of 3/ 16" ste el guy wire real cheaply at last year's flea market doesn't me an that it is suitable for use in you r installatio n. Like masts of uniden tified material, be very cautio us about using unide ntified guy material. High stre ngth grade is rated almost 30% lower th an E HS. Some other E HS sizes and stre ngths are: %" 6,650 pounds breaking strength 5/ 16 " 11,200 pounds breaking strength 3 / 8" 15,400 pounds breaking strength

Cable fittings The three most common methods of terminating guy wires are to use cable clamps, swaged or crimpe d presse d fittings or Preformed guy gr ips.

Cable damps T he most common, and the chea pest cable fittings are cable clamps. Always use three per joint and make certa in that the saddle is o n the live side o f the guy wire. \'V'hen you pu t your guy wire th rou gh a thimble or in sulato r and double it back to pu t your cable clamp s on it (this is called a

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Up m E TOII7ER

turnback), you have two different wires. T he continuous one that bears the weight of the guy wire for ces is called the "live" end and the sho rt piece that is turned back is called the "dead" end. It's "dead" because it is not weight bearing. The cable clamp consists of two parts; the U- bolt and the sadd le. The saddle portion provides the ma jority of the ho lding capacity of th e clamp. T he sadd le goes on the "live" side of the cable. The saying goes "don't sadd le a dead ho rse." In other words, don't put the sadd le on the dead side of the turnback. A clamp mounted backwards loses 40% of the ho lding capacity of a properly installed clamp. S EQU ENCE FOR INST ALLING CABLE CLAlvlPS:

1. Turn back the specified amount of wire from the thimble or loop (33/ 4" for 3/ 16" cable). Apply the first clip one base width from th e dead end of the wire . Install the U- bolt over the dead end of the wire, with the live end resting in the saddle. T ighten the nuts evenl y, alternating from o ne nut to another, until reaching the recommended torgue. 2. Apply the seco nd clamp as near th e loop o r thimble as po ssible. Tighten th e nuts finger -tigh t only. 3. Place the third clamp between the two, then tighten each U-bolt evenl y, alternating from one nut to the other until reaching the recommended torgue. When tighte ning cable clamps, torgue th em so that th ey are tight; a typical specification for 1/4" CROSBY clips is 15 foot-pounds of torgue . When assembling a tower, guy wires or antenna, let everything sit overnight; the n go back over ever y nut and bo lt the next day. You 'll be sur prised at how loose many of the connections have become. What the hardware is doing is going through one temperature cycle of expansion and contraction. By letting it cycle one or m ore time s; th en going over the hardware again , you'll eliminate the possibility of loose or potentially loose hardware.

Swaged fittings Swaged fittings produce a strong, clean connection; if yo u do n't

17-G uy

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117

lik e the cobbled lo o k of lo t s of cabl e clamp s , sw agin g may be fo r you. T he most comm on swages Photo 1:Aswagedguywiretermination. are N icopress fittings. Whil e th e fittin gs th em selves are relatively inexp en sive, you have to buy or rent a Nicopress tool to crimp them o nto the guy wire. And you can't remove the m o nce th ey're crim ped on.

Preforms Preformed guy g rips (or Big-Clip Dead-Ends) are the easiest to use, and naturally the mo st expensive. Yo u sim ply curl them onto th e end of the guy wire to produce a pe rma ne nt termination . P reformed cabl e grips have virtually replaced cable c Location of t his C Iamps lor po\ver, color code/cross-over mark telep hon.e, .and Ide~tiOn ~ is underneath communlca ti o n s compa n ies. Fac-

.

.

-

Color Code and

~~ro;;-OverMarkS

Short Leg ~ Long L~

to ry specs say th at Flgure 1: Phillystran grip. yo u ca n r em o v e and reapply the grips twice . I f removal is necessa17 after a guy grip has been installed for a period grea ter th an three month s, it mu st be replaced. If yo u can 't find the m lo cally, ham magazine adve rtise rs will be happy to ship you as many as you need. Pr eforms are co lor-coded for wire sizes, as follows: l/ s" blu e 9/.1 2" blu e 3 / 16" red 5 / 16" black 1/ 4" yellow 3 / 8" orange Use o nly the co rrect size Prefo rm s for the ca ble yo u are usin g. Ca bles and related h ardware, including cable clamp s and Preforms, are designed for a certain number o f st ran ds in the wire ro pe, and for a spe cific lay fo r each cable size. D o not m ix different hardware. N O T E : Prefo rmed g rip s have 2 sets o f cro ssover m arks. Th e se t clo se st to the loop is for no rmal g uy wire at tac hment. The set farthe st from the loop are for w he n th e guy wire goes thru an in su lato r.

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Installing Preforms Preformed guy grips are precision device s, de signed to be installed by hand ; do not use an y tools to install th em . They shoul d be in stalled onl y in conjunction with heavy-duty wire rope thimbles. 1. In sert a heavy-du ty thimble into the eye of th e Preform, th en through th e att aching hardware (shackle, etc.). 2. Wrap the first leg (eithe r one) around the guy wire with two complete wrap s. Simpl y wrap th em around th e guy wire. Line up the cro ssover m arks, then wrap the second leg with two complete wraps , ending opposite th e first leg. 3. Com plete the installation by either sim ultane ously wrapping both legs (keeping the legs opposite each other) or alternate th e legs a couple of wraps at a tim e. Bending the E HS guy wire as yo u wrap th e Preform leg around it will m ake it easier to att ach. 4. Finish th e sho rt leg first, then the long leg. 5. Seat th e ends of the legs by hand. If th at won 't do it th en use a flath ead screwdriver under th e end o f the strands. For Phil!ystrall you may need to sepa rate the strands to finish the ends of the Preform. 6. Attach a black tie-wrap o r end sleeve around the grip at the end to secure it.

Cutting guy cable Many different methods have been used over the years to cut guy cable. T hese days, E H S (extra high strength) guy wire is th e standard and special cutter s are needed to cut thi s hard wire. Always wear your safety goggles when working with guy wires. T here can be lo ts of m etal chips floating aro und when you cut th em o r th e guy wire can easily whip around and hit you in th e face or o ther bod y parts. An older method of cutting guy wire is to use a big chisel and a hammer to split the cable . T hese days you can rent or borro w a boltcutter. Ju st make certain it will cut E H S, not just so ft m etal. Another m eth od is to use a circular power saw with a metal cutting agg regate blade. T hese blade s are less than $4 at your neighborh ood

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hard ware sto re and will cut pipe mast material as well, A hand grinder wo rks very well also. \X1ith guy wire, use electrical tap e not only to ma rk where you wa nt to cut bu t also to pr event the guy wire from unraveling after it's cut.

Phillystran ® Introduced in 1973, Phil!y.rtrall gives the strength o f E HS steel wire with th e added adva ntage that it is nonconducting, thu s it's electrically trans parent to RF. It consists o f a polyureth an e resin im pregnated aramid rope with a thick extruded jacket o f specially fo rmulated p olyurethane. Its nonconductive property ma kes it ide al for tower syste ms where so me ante n nas will be under o r clo se to guy wires. G uy wire interacti on with stacks and wire antennas will be eliminated by using Phil!y.rtrall. When the original Phil!p tran was in troduced , only speci al (and expe nsive) cable end soc kets could be used. Besides costin g $18 each thirty years ago, yo u had to pot each so cket end with a special, m essy potting compo und. A new, improved Phil!pfran was introduced several years ago th at not onl y co nsists of a new core formula but also a different jacket material,

The new Phillystran cable grips T he ma nufac ture r recently introduced Phil!y.rfrtlll compati ble Pr efor med guy g rips, o r, as the y call them , Big Clip Dead-Ends. What mak es the se different than the ones that you use for no rmal v, " o r 3 / 8" E HS is that these are longer than no rm al and have a different lay (twist) to match the characteristics of Phil!y.rtrclil. They are installed generally the same way, except that you must keep so me te nsio n on th e Phil!y.rtran while installing th e Pr eform, and you may have to split the stra nds o n th e en d o f th e Preform in order to finish wrap ping th em on. T his is because the Phil!y.rtran is very flexible, particularly whe n compared to good old E HS. O the r tha n th at, they're just like the Preform s tha t you're used to using.

Guy wire interaction and segment lengths It is commonly accepted th at metal guy wires interact and influence RF rad iation. AM rad io towers are loaded verticals and th eir

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owners go to great lengths to isolate them from their guy wires. Some amateurs have used their calcu lators to determine non-resonant lengths for use on their towers, and felt satisfied with their conclusions. I've seen guy wire segment lengths of 22 or 26 feet used as commonly accepted benign length s. O f course, you could neutralize the who le problem by using Phil/ystran but amateurs being a parsimonious bunch typically blanc h at the thought of spending that kind of m oney. Suggested non-resonate guy length s can be found in the ARRL An tenna Book. A we ll known co ntester and respected station builder, Lew Gordon, K4VX, wrote an article th at appeared in QST (August, 1993, page 22). It argued tha t his computer modeling revealed that altho ugh co nductive guy wires do distur b the patt erns of an tennas m ounted on towers, "these effec ts are of no practic al imp ort ance." You can decide what works for you.

Pulling the guy wires Once yo u've got the guys cut to their appropriate length s and h ave them attached to the tow er, you need to pull them so you can attach them to th e turn b uckle at the guy anchor. One method is to pull the m by h an d with a moderate amount of force and then sec ure them to the anchor. T his will de flect the tower sligh tly b ut will put some ini tial tenPhoto 2: KleinChicago grip. sio n on them. Another method is to use a come-along an d ca ble grip . Use one of your nylon slings around the guy anchor for attac hment of the other en d of th e come-along. With just one of each you' ll spend a lo t of time rigging and derigging it and taking from anchor to anchor. If possible, use of 3 come-alongs and 3 grips will let you do it much faster and easier. In the absence of a Klein grip or similar pull er, you can use an extra Preformed grip as a temporary attachment point fo r your comealong. Since you'll be using it a b unc h of tim es, you can't use it as a permanent grip but it's fine for a temp orary.

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Guy tension O ne thing I can guarantee you is th at 90% o f hams don't know what their guy wire ten sion is and also that it's eithe r too m uch o r too little - usually the latter. As far as guy wire tens ion, the rule of th umb is to ten sion the guy to 10% of its b reaking stre ngth. With 3/ 16" EHS th at wo uld be approxima tely 400 po unds. H ow do you know whe n you've got the right amo unt of ten sion ? One way is to put an instrum ent called a dynam ometer inlin e and m easure the tension directly. They're expe ns ive to bu y ($ 900 !) , bu t can be rented. I fou n d o ne in Seattle for $40 a d ay, bu t it too k s ev e r a l p h 0 n e Photo3:ADillon Dynamometer. calls to fin d it. An accura te, inexpen sive device for m easuring b'UY ten sion is now available. It's th e Loos Tensio nometer an d was d esign ed to b e used for tensioning sailboat rigging but works very well wit h ham tower guys. It' s also easy to use. I ran a test with the Loos against an expensive calib rated Dillo n dyna mo meter and the Loos was sur prisi ng ly accurate. T hey 're avai la b le fro m Champion Radio Products (www.championradio.co m). W hile the Loo s was deve lop ed for ten sionin g sailboat rigging (typ ically Photo 4: Loos PT-2 tension meter.

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7x19 stainless steel cable), it can be used for other materials . As the tensio n o n a cable is increased, it becomes more rod-lik e. I put som e 3/ 16" E H S in series with so me 3/16" 7x19 galvanized cable and a length of HPTG4000 Phillystr an and put 400 pounds of ten sion o n it. I used a recently calibrated Dillon to set the tensi on. Then I me asured each segment of cable and the y all me asured within a couple o f perc ent o f the Dillon, pro ving the accuracy and usability o f the Loos for different materials. The only caveat is th at since Phillystran is typically thicker than its wire cou sins, o nly th e HPTG4000 will fit into th e keeper at the top o f th e Loos to be m easur ed directly. Since recommended Phillystran install ation calls for steel cable from the end of the Phillystran (abo ut 10-15' up) to th e anchor, you can me asure th e tension on th e steel with no problem. The reason for the steel down to the anchor is not only can the Phillystran be cut easily with a razor knife, but also the PVC jacket can also catch fire either from vandalism or a ground fire causing a tower failure . Even if you have to estimate guy tension, the important point is to tighten all the guys so th ey're all approximately the same. H aving them all equalized is mech anic ally important.

Safety wiring turnbuckles The last thing you do to your guy wires is to safety wire th em. T he idea is to keep th e turnbuckles from unwinding accidentally.Just take so me pieces of leftover guy cable (yo u'll have lots of it) and loop it through the anchor shackle and the turnbuckles, securing the ends with a cable clamp. If you exte nd the safety loop thru th e anch or as well, you get addi tional safety in case of turn buckle failure.

18 TOWER ERECTION Okay, you've completed th e permit proc ess, you've spent th e money for th e tower and the ho les have been installed. Now you're ready to finally start headin g up-upward s toward RF nirvana. Let the erection begin !

The LXC Maxim of Manageability As you start to co nstruc t your tower, my advice is to break everything do wn into bit e-sized pieces and just do one step at a time . Trying to co mbine two o r m ore steps in th e same task is asking for tro ub le. What I mean is don't try to bring up th e guy wires already attached to the tower sectio n; bring them up after the sectio n and guy br ackets are in stalled. D on't bring the feedline up with th e antenna; instead put a jumper from the feedpoi nt to the m ast or anten na switch and br ing up the feedline sepa rately. Anytime you violate thi s m axim, you' ll usu ally wind up doing things twice, along with und oing what you've already done. You' ll be mo re efficient by doing things o ne step at a time .

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Prepping the tower sections Fo r a Rohn round-legged tower such as 25G and 45G, the re are severa l things you can do to make your job easier. D o these while the tower sectio ns are still on the gro und, First, the re will be galvanizing in man y of th e leg bolt holes on new tower sections, They've been ho t-dipped galvanize d and th ere'll be lots of galvanizing aro und so me of the ho les, You won't be able to ge t your bolt through some of the m witho ut a lot o f effort and gouging up the leg bolts. Rohn cauti ons no t to drill them o ut. Use your driftpin or taper punch and a hammer to enlarge th e hole. O nly drill it as a last resort, and then o nly enough to clear o ut th e hole. Next, check th e inside of each lower leg for that same galvanizing problem. A ro und file will tak e care o f an y exce ss in side . Believe me, it's much easier to do on th e ground than up in the air. T hird, fit the section s together to insure a relatively easy fit. You may find that one leg won't line up; this isn 't un common. With a piece o f pipe or another tower section, gently bend the o ut-o f-line leg until it slips on. This also is easier to do on th e gro und. Us ed tower sections will generally slip toge ther more easily because th ey've already been installed, bu t pr e-fitting the m on the gro und is always recommended . Mark both legs with tap e o r a felt marker to insure th ey go together the same way the y did on the gro und. T he last thing to do to your round legged-tower befor e you start sen ding th e sectio ns up is to pu t so me grease aro und th e inside o f each lower leg. Not only will th ey slide on mo re easily d uring installation bu t also th e grease will help to minimize corrosion and oxida tio n between th e sections and make removal easier. If you skip this step, it may take a hydraulic jack or scisso r jack to pr y th e sections apart when you want to take it down . If you want to have th e towe r co nduc tive, e.g., you' re going to shunt-feed it, then use an antioxida nt as the leg grease to promote good electrical co nt act .

Section stacking After rigging th e ginpo le (the haul ro pe goes up the m iddle of the pipe, acro ss th e pulley, the n down to the load), attach the leg bracket to the top of the top section , below th e top brace. Make certain that it's secure be for e you push the ginpole ma st up to th e

18-T OWER

extended position where it'll be ready for the lift. Your gro und crew will attach the haul ro pe to the sectio n and, on th e command of th e tower climb er, will start to pull on the haul rope. Route th e haul line th rou gh a snatch block (a snatch block is a pulle y that op ens up at th e top so you can put it in the middle of a rope) at the bottom of th e tower to transfer the hauling effort from pulling down to pulling ho rizo ntally. Pullin g vertically is all arm streng th plus you're a likely target for falling obj ect s being close to the tower. Us ing the snatch block will let you pu t th e ro pe aro und your hips and just walk back wards to pull the load up. You'll be using larger muscle g ro up s, and hoisting will be much easier in addition to being able to

ERECTIO N

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o f the danger zone. Anyti me yo u ne ed to ho ld onto a haul . . rope, put it around yo ur hip s, th en b ring th e '.~ . 1'1 ' tail end o r de ad end in fr ont of yo u. D O N OT tie the ro pe aro und yo ur wai st - thi s is potenI I tially dangerous. Aiming th e tail end in th e same direction as th e load ro pe, grasp both ro pe s with o ne o r both hand s while wearing leathe r Drawing 1: Rohn gloves. T his is th e best way to hold o nto o r ginpole, drawing brak e a rope load . Don't depend on jus t us based onEF2545. ing yo ur hand s; it's no t as reliab le a tec hn iq ue and yo ur hand s will qui ckly tire. Wit h th e ro pe se cur ed aro un d yo u, yo u can comfortab ly hol d it for q uite some time. The tower section should be rigged so th at it goes up more or less ver tically; the heavier th e sectio n, the more imp ortan t this becomes. Put a sling around a leg at about 3/4 o f the way up th e sectio n and th at'll be your pick point . As soon as it clears the top of the tower, yell "stop," then "down slow" when yo u're ready to have the sectio n delivered where you want it. If two legs are o ut of alignme n t, use yo ur come- along to pull th em togethe r, o r put th e com e-along aro un d th e bottom o f th e whole sectio n an d tighten it up to pull th e legs to gether.

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This is a common p rac tic e w hen putting up BX and Tr ylon towers. If you don't h ave a co me-a lo ng, ra tche t o pe ra ted tr uc k straps work great. O ne person on a tower doesn 't have a w ho le lo t o f leverage, an d if yo u fin d that the sectio ns lin e up b ut you ca n't get them to slide down, get o ut th e come-alo ng or Tower*Jack an d p ull it down in to place . T he Tower*Jack is a hinged device that allows additio nal leverage when pr ying sections apart or pul ling the m together. T he latest version also has a leg aligner so you get two hand y tools for th e price of one. They're ava ilab le from C ham pion Radio Products (www.championradio.co m) . Stack an appropriate nu m ber of sections (typically up to the ne xt guy point), then br ing up the first set of gu ys and attach them. Your ground crew can use their cable grips and co me -alongs to put the initial ten sion on them , then attach th em to th e anchors. You'll be ab le to tell them which ones to tighten and which ones to loosen as you use your level on the leg to plum b the tower. Once th at's done, all you have to do it repeat the same steps until all the sections are in place and guyed. The most imp ortant part of the tower erectio n to plumb is the first segment including th e first set of guys. Once that segme nt is plumb, all you have to do is look up th e face of th e tower an d you 'll be able to see if ever ything above it lines up - it'll be pretty o bvious. If it doesn't, just ad just the come-along or turnbuckle to get it straight.

Installing the mast T here are two methods for installing your mast. For sma ll and medium sized masts, just use your ginpole to br ing it up and drop into the tower from the top. U se a long sling as a choker by wrapping it aro und the mast two or three times, then put it through its own loop. The choker should be above the balance point so that the mast go es up vertically. This is relatively easy. If you've got aspirations for big antennas or stacks of antennas, you're probably going to have a big ma st. T hese can weigh over 100 pounds and are typica lly 20-plus feet long. A twenty-foo t ma st is about th e limit for a ROHN ginpole as the net working height is only abo ut ten-feet, plenty for a ten-foot section but marginal for a hefty twenty-foot mast. It's a lo t of work to get an industrial streng th mast

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up high eno ugh to clear th e to p o f the tower, th en lowered down into the thr ust bearing. T here is a sizable pu cker facto r if yo u're the guy on the tower with this big piec e of metal hanging over your head swinging aro und. An easier alterna tive is to put the mast inside th e tower at an early point, after you've go t perhaps two section s, or twenty feet, o f tower installed . Lift up the mast with the ginpole and, mu scling it int o place if nec essary, lower it down so that it rests o n th e concrete base pad. Co ntinue building yo ur tower. Yo u 'll ne ed to bring it all th e way up through th e tower, through th e rotato r she lf and then up through the top plate and thr ust bearing. T his ca n be eas ily done by using the gin po le, fee d ing the hau l lin e th ro ug h a face o f th e tower ne ar th e top an d lowering th e hau l lin e down th e m iddle o f th e to wer. Tie a choker around the m ast abo ut 1/3 o f the way down th e m ast and clip yo ur ca rabine r to th e haul line. T h en yo u and a couple o f friend s ca n pull th e b east up . All you have to do is to ste er it through th e thrus t bearing and secure it. Once it is held by the thrust b earing, re-rig it to pu ll it up th e rest of the way. Th e only thing yo u must do is slide yo ur ch o ker fur the r do wn the ma st. O nce th e mast is po king up above the top o f th e tower slightly and is cap tured by th e thrust bearing, thi s is an opportunity to in stall the first, or to p, an tenna on the mast. If you're really planning ahea d, you've mea sured and marked wh ere each antenn a will be m ounted and where the thrust be aring will be. Once the first ante nna is installed, pull the mast up with the co me -along to the point where you can attac h th e seco nd antenna . Hoist again and you've go t three antenn as installed. Repeat the sequence until all the ante nnas are installed. Be certain to mark the spa cing measurement with a felt pen while the ma st is on the gro und to avo id any stacking co nfusion. Be very careful about yo ur rigging and where yo ur hau l rope travels over the tower part s. Hav ing the haul ro pe pass over a ro und brace is okay, bu t you don't wan t it to pull over some thing sharp, such as the edge of the ro tator plate or something similar. Ea ch antenna on the ma st sho uld be ins talled with a jumper from the feedpoi nt (since it' ll probably be o ut o f reach) long enough to reach th e m ast, where it'll eve ntually be connected to its main feed line or relay box. D on't try to in stall any antenna with the entire

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feedlin e already atta ched. It' ll give yo u lots o f heada ch es during installatio n and you'll invar iably wind up rerouting it anyway.

Antenna stacking sug gestion In most installations, I recommend placing the 40-meter bea m o n the bottom of the stack, just above the top of the tower. Over the years you'll typically have to do mo re maintena nce on bigger bea ms than any tribanders o r mo no ba nders, an d its much easier to take down and wo rk on if it's o n the bottom o f the stack. T he increme ntal increase in heigh t as a percentage of wavelength tha t you gain by putting the 40-meter beam on top is not ve ry significant ove rall (an additio nal ten feet on 40-meters is only 7% o f a wave length). I think th e greatly im proved ability to work on it mo re than makes up for any compromise in height above gro und.

Installing the rotator While the rotator is still on the gro und, hook it up to the contro l box and test its ope ratio n. D on't wait until it's up o n the towe r to find o ut tha t it doesn't wo rk. Afte r yo u're assured that the ope ratio n is satisfactory, turn the ro tato r until it indicates north or ano ther known direction, then ge t it read y for hoisting. It doesn't really ma tter which way the ro tato r is physically installed in the tower as you' ll be able to orient the ante nnas whe n you mount them o n th e mast. If yo u skip this North -o rientation step, you won't know what the ro tator directio n is once it is installed an d you'll have to stop everything while you hook up the cable and co ntrol box and dete rmine the direction. T his is a was te of time ; plan ahead an d do thi s befo rehand. To haul up the ro tator, clip a carabiner o nto a U-bolt or thrubo lt on the neck o f the rotator o r put it in a bucket. Bring up the ro tator, install it under the mast, let the m ast down an d most o f the heavy wo rk is done. W hile other ro tato rs and newer H y- G r\ IN mo dels have cable plugs th at make it easier to do it in ste ps, trying to atta ch the rotator cabl e to th e terminal strip on the bottom o f a T2X o r Ham IV is painful but manageab le up on the tower. To haul up th e control cable separately, simply tie a lazy overhand knot in the cable and snap that into your hauling carabiner. I used to recommend th at th e weight of the ma st and antenna system be taken up by the thrust bearing and not the rotator. This

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may be done by p utting a screwdriver un der the bo ttom o f the mast, between the mast and top of th e ro tator, and prying up eno ugh to lift the mast off th e ro tator. Tight en th e thrust bearing bolts first, then the rotator U-bolts o r clamp bolts. This will ins ure that the thrust beari ng is holding th e mas t and ante nna weight and no t the ro tator. A case can be made fo r putting weight o n the ro tator. The rotators typica lly run on so me sort o f bearings and the bearings sho uld be seated in or de r to ope rate as design ed . In the case of th e Orio n 2800, the factor y recommends th at th e entire weight of the syste m should be ON the ro tator. \,(!hile I'm no t aware of any lo ngter m ro tato r failure trends du e to them no t suppo rting any weight, it's probably best to have so me weight on th e rotator. This isn't a simple task (e.g. H ow much weight? How do you me asur e it?) so the choice is ultimately up to th e user and I don' t think you'll have a problem eith er way. To minimize the po ssibility of bind in th e rotator /mast/thrust bearing system, wo rk your way down when doing the final tightening. D o the thrust bearing first, the rotator mas t clamps next, the rotor shelf bolt s, and th en th e rotato r base bolts last.

Rotation loops There are 2 ways to make a rotation loo p for your cables. O ne way is to tap e all th e cabl es coming down the mast togeth er and th en allow an extra 3-4 feet before securing it to a tower leg. The bundle will have so me rigidity and tha t will help keep it out of harm's way. Make sure that it doesn't snag o n anything and you'll be good to go . The seco nd method o nly wo rks if yo u have a flat-topped tower. You wind the cable aro und th e mast 2-3 times in a diam eter that is smaller than the top plate so that it lays o n the flat surface. T his is the sam e me thod used by th ose pneumatic masts mo unted on electro nic newsgathering trucks.

Securing cables down the tower While electrical tape doesn't have much streng th, it's sufficient for a small number of cabl es tap ed to the tower leg. Additional stre ngt h can be o btai ned by using tie wra ps. Black o nes can be good in UV but white o nes will deterior ate rapidl y. In either case, wrap-

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ping them with a layer or two of electrical tape will prevent any UV damage. For bigger bu nd les of cables or bigger, heavier cables, use of a hoisting grip is a good method. A Ke llum grip is a closed woven sleeve that ho lds the cable like a Chinese finger pu zzle - the more you pull it, the tighter it gets. T hey are sized very specifically. It's easy to pass a naked cable thr u it but it's no t easy to put a piece of RG-8 with a PL-259 on the end thru it. Andrew also makes woven hoisting grips but theirs are open and you sew them togeth er with a supplied piece of small wire. T he advantage here is tha t they can be installed anywhere on the cable and the grip can be pushed together to allow a co nnector to pass thru it. A simpler, cheaper way to go is to use a ho se clamp at the top of the tower to take the weight . Be careful no t to deform the cables and this will work fine.

19 MASTS The mechanical design of any antenna system is even mo re important than the electrical design , as a critical mechanical failure can wipe o ut even the best electrically designed antenna. O ne extremely imp ortant part of any rotating beam antenna system is the mast; the pip e which supports the ante nnas themselves and coup les them to the rota to r. A typical antenna system cons ists o f a tower with a rotator mounted inside and several feet below the top of the tower. A mast is clamp ed to the rotator and extends several feet above the top of the tower. One or more beam ante nna s will be mount ed on that mast. The "design" of the ma st, in this case, co nsists mostly of determining the alloy and dimen sions since all masts will take the same basic shape of a cylindrical tube or pipe. T he design of the system will also include making sure that the ante nna loads are properly distributed and not too great for the mast chose n. The overall objective is to make certain that the mast will not permanently bend when subjected to high wind forces.

The Math T he m ath and physics involved with mast specificatio ns is o ut-

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side the scope of this bo ok. For the best discussion of this topic, read the excellent tre atise Ph ysical Design of Yagi Ante nnas by Dr. David B. Leeson, ex-W 6QHS, now W6NL. ! This is a great additio n to your tower library.

Pipe vs. tubing The industrial use and characteristics of pipe and tubing are very different. Tubing is rate d for yield strength whereas pip e is typically not. Pipe is most commonly used for transporting liquid s wh ere yield strength is not a facto r. Heavy duty pip e can be rated as Sched-

,- . Specification

Pioe Drawn aluminum tube

Extruded aluminum tube Structural steel Carbon stee l, cold drawn

Alloy steel

Sta inless steel

A I20 A53 ,A I06 606 3-T5 6063-T832 606 1-T6 6063-T 835 2024 -T3 7075-T6 A36 1016 1022 1026 1026 heat treated 1027 1041 1144 2330 4 130 co ld worke d 4340 1550 degree F quenc h AISI 405 co ld worked AISI 440C hea t-treated

Yield Strength, Ib/ln'

Not rated 30,000 15,000 35,000 35,000 40,000 42,000 70,000 33,000 50,000 58,000 72,000 85,000 70,000 87,000 90,00 0 119,000 75,000 162,000 70,000 275,000

ule 40, Schedule 80 o r ano ther such rating. \Vhi le pip e can be very heavy, that doesn't directly tran slate into strength, spe cifically yield strengt h. For sma ll sized installations where you are either installing small antennas or have th em mounted right at the top o f th e tower, yo u can probably get away with pipe but it has its limitations and sho uld be avoided if at all possible,

Ma st streng th When specifying a mast, it is importan t to choose a stro ng alloy. 1. D avid R. Lesson, "Ph ysical D esign of Yagi Antennas," (American Radio Relay League, 1992),

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All me tals hav e a prop erty called "yield stre ngth" which is a measur e of the poin t at which a metal will perm anentl y defor m (bend) unde r stress. It is th e yield strength which determines the suitability o f a ma st for an application; exceed th e yield streng th and you' ll have a failure. The high er the yield strength, the better tha t alloy will be for a mast; also the mo re expe nsive. Another fact o r beside the alloy th at has a significant effect on the relative strength of a mast material is th e mast fabr ication process. Fabrication categories o f carbon steel tubing are electric resistanc e welded (E RW) , cold-drawn butt welded (CD B\XT) , cold dr awn (CD) and drawn over mandrel (DONI). In additio n, heat treatm ent is a major variable in ste el. It makes a big difference in strengt h and can be worth the additional cost.

Mast size Just abo ut every thing having to do with H F beam installatio ns is geared to a two-inch on (o uter diam eter) m ast. Ma st m ounting brackets, U- bolts, rotators, tower ro tator shelves and th rust bearings are all de signed aro und a two-inch mast. If you wind up using water pip e, it has a 1.9" O D. and will caus e your rotator to turn slightly eccentrically if you use a thrust bearing. Mos t VH F /U H F ant enna hardware, o n the other hand, is design ed for m asts of 1.50" to 1.75" O.D.; the standard for m ost TV antennas. If you have a large array, you m ay cho se to use a three-inch mast. R OH N makes a three-inch thrust bearing so th at is no pro blem. The Y AE SU and th e O RlON rotators use a self-aligning ma st clamp that will accommodate just about any size ma st. If yo u standardize on two-inch hardware you won't go wrong.

Wind load This is the term enginee rs use wh en designing towers and other str uctures. T hese are the mini mum s, and yo u should increase the wind spe ed figure if you live in a spot th at has po tentially higher wind speeds, such as on to p of a ridge o r near water. Calculating wind load ing is an en gineering exer cise expl ained exten sivel y in th e Leeson bo ok . What's im p o rtan t here is that wind sp eed , alo ng with antenna load in sq uare feet, are the two det ermining factors for tower construction and ma st se lecti on.

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The wind sp eed s fo r all U S counties can be fo und in the latest TIA-222 publication and also on the Ch am pio n Radio Product website under T e c h N o t e s (www. c h a m p io n ra d i o. c o m/ win d spe ed .p hp). It's a good id ea to confirm this wit h yo ur lo cal building department since sometimes their win d speed is differen t (high er) than the TIA-222 rating. There are several ma st calculators available. There's at least one on the internet and you can also get an inexp en sive one from Champion Radio Products; the Mast, Antenna and Rotator Calculato r (MARC) Pr ogram. You should also increase the engineering factors if you anticipate ice loading. If in doubt, you'll never go wrong by over-enginee ring your installation. Figures and specification s in the ROHN catalogs for amateur to wers typically use 70, 90 and 110 MP H. N inety miles per hour corresponds to a pressure of 32.4 pounds per square fo ot. An increase of wind speed from 90 to 100 MP H (approximately 11%) increases th e pr essure from 32.4 to 40.0 PSF (approxim ately 23%). T his is not a linear relationship; a sm all increase in wind speed pu ts a lot of extra stress on an antenna system. •

I

•

1

-

-

••

Mean Velocity

10.0 PSF 14.4 PSF 20.0 PSF 30.0 PSF 40.0 PSF 50.0 PSF 60.0 PSF

50.0 MPH 60.0 MPH 70.7 MPH 86.6 MPH 100.0 MPH I l1. 8 MPH 122.5 MPH

Table 3 . Sample Bending Moments & Yield Strength Sample anlennaIs SlepplRelementyaglwith 9.7 squarefeel of windIoading calculatedwith Mast, Antenna andRotatorCalculator(MARC) Program, avaIlable fromwww.champlonradlo.com.

Windspeed

70 MPH

90 MPH

I IOMPH

Antenna height above tower

1 foot 5 feet 10 feet I foot 5 feet 10 feet I foot 5 feet 10 feel

Bending Moment

2344 in-lbs 11,987 in-lbs 24,645 in-lbs 3903 in-lbs 19,962 in-Ibs 4 1,042 in-Ibs 5471 in-Ibs 27,981 in-lbs 57,527 in-lbs

Recommended yield strength

15,000osi 39,000 osi 46,000 psi 87,000 osi 46,000 psi 87,000 psi 25,000osi 55,000osi 115,000 psi

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Aluminum masts From the tab le, you can see th at the yield strengths of some types of aluminum tubing will hand le decent antenna load s. There are two major problems, however, even at higher yield streng ths. Aluminum can pro vide reduced fatigue life. And alumin um will gall ov er tim e if it is subjected to rubbing against a harder m aterial such as a steel U-bolt o r SS bolt int ended to pin th e ma st to th e rotator. Be cauti ous abo ut using aluminum masts in critical applic ations sinc e the y only have a moderate am ount of yield strength, and don't use one at all if it has no alloy markings o n it.

Steel mast coatings Steel masts must be coated to prevent ru sting. The m os t comm on treatm en t is to have the mast hot dipped galvaniz ed. If your mast doesn't come treated this way, you may be able to get it done locally if you live in a populated area. G alvanizing co sts approxima tely 50 cents per po und of material with a typical l Oa-p ound m inimum. If you're not able to have your mast galvanized, yo u can do a pretty fair job your self. Clean the mast thoroughly wit h a good paint thinner, T SP o r solvent , then appl y a suitable coating. Two coa ts of a quality cold -galvanizing paint , such as the LP5 or RJlstoletlJJl prod uct s, works well as do a number of marine coatings. I' ve tried th e Hammerite coating and it doesn' t adhe re very well; it flakes off whe n you're working o n the mast. It cont ain s glass flakes and doesn't seem well suited to our ma st application . O the r steel co atings such as epoxies are available and are wo rt h loo king into especially those fo r marine service. Put a cap o n th e to p o f the mast to keep water out and you' ll be all set.

Steps If you're goi ng to have mor e tha n o ne antenna on your mas t, at so me point you're going to want to b e ab le to wo rk on th e top antenna. If it's o ut of reach , you'll need some ste ps to climb th e mas t. The simplest one is made out o f two o r three-inch steel angle iro n o r aluminum and a length o f 15 to 18 inch es is ideal. Drill two hole s to take a two -inch U-bo lt (if you have a two- inc h ma st) and install the steps at convenient distanc es up the mast. Install them with saddles if possible and the y'll be both safe and comfortable. You

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may either leave th em up perman ently o r just put th em o n wh en yo u need them. I always car ry a co uple o f steps in m y toolb o x becau se I never know when I might need them. A wo rd to th e wise, file down th e ends and edges of your angle iro n step so that yo u don't go uge yourself accidentally. Welded steps are good too, just more wo rk. I f yo u we ld steps onto th e mast, weld one o n each side of th e mast so that you can stand and wo rk fo r as long as yo u need.

Parking your antenna system There is mu ch de bate on how you sho uld pa rk your antennas in o rde r to minimize wind damage. So me say pointing the elem ents into the wind gives you the strongest materi al (the boom) for the wind to wo rk against, others say that the opposite. T he maximum wind load is when eith er th e boom or the elements are at a 45 degree angle to the wind so ob viou sly th at's to be avoided. If your tower and antenna system is engineered and built to the weathe r conditions you'll encounter, you' ll probably be okay no matter which way the y're pointed. If not, be sure your homeowner's insurance is paid up and cross your fingers whe n th ose big sto r m s roll in.

20 COAXIAL CABLE These days it's easy to spend hundreds of do llars on coa x. T he price o f copper ha sn't go ne down in recent memory; if it's been so me time since you 've bought an y, sticker sho ck may well set in. \'Vhen selecting coaxial cable, there are four major area s of electrical characteri stics to conside r. These are att enuatio n, VS\'VR, power ratings and shielding.

Attenuation Attenuation is the measurement of sif,'11al loss in a cable as a result of inner conductor loss, oute r conductor loss, dielectric loss and radiation loss. Abo ut 90% of the attenuati on comes from the inner and outer conductor loss, while about 5% to 7% is from the dielectric loss. Attenuation may be expressed in the form of a perc entage of transmission efficiency. Total Attenuation 1.5 dB 3.0 dB 6.0 dB

Efficiency 71% 50% 25%

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In o ther words, with 3 dB of attenuation, 100 watts out the back of the rad io res ults in 50 watts at the antenna. T his attenuation works on recei ve also; a 3 dB loss means that the rece ived signa l loses half of its signal strength as well.

Voltage Standing Wave Ratio (VSWR) VS\VR is the ratio of the ma xim um voltage amplitude to the minimum voltage amplitude in a transmission line. Lengthy, authoritative tomes concerning transmission lines and loss are availab le to the reader and lie outs ide the scope of this book. For many amateurs, an SWR of less tha n 1.1:1 is the only acceptable reading. Other authorities have different ideas and regard high SWR as little more than a nu isance. You kno w which camp you're in . Sometimes varia tions of conductor and dielectric diameters are introduced during the manufacturing process which would affect the VSWR. These abnormalities lo ok like bumps, corrugations or other irregularitie s that are visible on the jacket. T hese irregularities typically come when one manufacturing ro ll-end is spliced onto the end of another.

Power ratings Power ratings come in two categories; peak po wer and average power rating. The peak power rating is limited by a vo ltage breakdown between the inner and outer conductors and is indepen dent of frequency. The average power rating is go verned by the safe long-term operating temperature of the dielectric material and decrea ses as the frequency increases. A cable with a solid dielectric will handle higher po wer than a cab le with a foam dielectric. RG-8/ U with a solid dielectric will handle 5000 volts ma ximum w hile the same cab le with foam dielectric only has a 600 volt rating. Many amateur transmitter dut y cycles are so low that substantial overload is permissible on current peaks so long as th e SW R is relatively low, such as less than 2:1.

Shielding This is the ability to keep unwanted signals out and wanted signals in. Most high grade coax has 96% shield while BELDEN 99 13 and its relative s have 100% shield. If yo u don't mind hearing from

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your neigh bors occ asionall y, less shielding may be worth the bargain price. Otherwise, stick to th e good stuff; remember, you get what you pay for.

Connectors Co nsiderations sho uld be given to co nnec tors as well. Not o nly the type (UHF/ PL- 259, N-type, etc.) but also th e mate rial is important. T he connector material be co mes a factor over tim e as the m aterial oxidizes. Gold or silver oxides are co nductive while nickel oxides are ferro magnetic and can cause non-lin earities and IMD problem s. Silver connect or s sho uld be your long-t erm choice. T hey also take solder mo re easily than their nickel-plated cousins. So far as peak power han dlin g rati ngs of co nn ecto rs, bo th UHF and N -t:ypes are rated at 2.0 kV D C vo ltage with a p eak power of 10KW at a VSW R of 1.0. Anyo ne who 's tried to run 5KW int o RG -8/U with PL- 259's o n it will tell you th at those figures are probably opti mistic. For VHF/UHF or even serious HF applications, N -type conne ctors are the preferr ed ones. T hey have slightly less insertion loss than PL259's but their main advan tage is that, unlike PL-259's, they are waterproof; there is a rubber a-ring gasket betwee n connectors that insures that no water can get in. T hey're more expensive and you'll have to stock up on adaptors, elbows, barrels, etc. but it might just be worth it. For VHF/UHF applications, it is a given that you should use them.

Veloci ty fac tor The spee d of RF travelling through coax is determined by the dielectric material used in the core. Solid polyethylen e, such as used in RG -213, will slow the signal to 66% the speed of light.

Impe dance Altho ugh coa xial cable can be manu factured fo r any impedance value from 35-ohms to 185-ohms, the most common coaxia l cable impeda nce used by amateurs is 50-o hms. Transmitters, lowpass filters, amplifiers and antennas are generally designed for 50ohm unb alanced ope ration. T he reason for th e 50-o hm characteristic is that it is a compromise between low attenuation (75-o hms ) and po wer handling capa bility (30-ohms) .

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Bending radius A normal amateur insta llation will crea te bends and turns in the fecdline run. Bendi ng coa x is acceptable as lo ng as the minimum bendi ng radius is not violated. A typical bending radiu s is a mu ltip le o f the coa x diam eter. Fo r example, a common spe c for RG -8 minimum bending radiu s is 4 inches, which is a multiple of 8 (1/ 2" O D X 8). T here is a bending rad ius parameter for all coa x cabl es so do yo ur homework and treat the coax with care. Coa x with mor e rigid shield materials will have a larger bendi ng radiu s.

RG-8/U vs RG-213 T he m ost common coax used for amateur applicatio ns is RG8/ U. Altho ugh one brand of RG-8/ U is basically the same as any other brand, there is often a significant difference in the qu ality and co st o f the materials and in the manufacturing consistency and qu ality. As with m any other things, with coa x yo u get what you pay for. The easiest way for m anufacturers to cut the cost o f their coax is to cut down th e amo unt of copper braid in th e shield. A shield coverage o f 97% indic ates a high-quality coax, but if you can see a lot of dielectri c showing through th e br aid, it's pro bably a lower gra de coax. RG -8/ U has a cellular polyethylene (o r foam) inner dielectric and a black PVC jacket. Many ama teurs insist on using RG-21 3/ U which, altho ugh it is slightly lossier th at RG-8/ U, offers two significant benefits. First, RG213/ U is a des ign ation th at can only be used by cable s manufactured to th e military spe cificatio n for that cable, both for materials as well as manufacturing processes. This results in a mo re consistent product th at doesn 't have sloppy splices in th e middle of it. Using RG-213/ U minimizes this kind of potential problem. Ano ther advantage of R G-213/ U is th at the jacket is made fro m no n-co ntaminati ng PVC unlike regular RG-8/ U. Any cable used outdoors is subject to years o f sunlight abu se. The UV radiation fro m sunlight causes a chemical reaction with the standard PVC jacket material and the chloride from th e jacket material (polyvinyl chlor ide, remember?) starts to migrate, o r leach, toward the inner dielectric and throu gh th e copper braid . Not o nly does th e braid get all gumme d up, bu t also it degr ades th e performanc e of th e coa x and it only ge ts worse over tim e. In an extreme case, the chloride will coat each

l O -C O AXIAL CABLE

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strand of braid and actuall y insulate each strand from th e o thers. You 'll have continuity o n each strand bu t not from one to the other. The SWR of the coax (no t the antenna) will rise over tim e du e to th is feedline degradation and you'll have to replac e it. If you are in the Sunbelt o r are at a higher than average elevation, th e non-contaminating jacket is probably mand ator y. In the cloudy Pacific Northwest, it is not as critical for long-t erm reliability. A disadvantage of RG -8 with foa m dielectric is that the foa m will cold flow over time. T hat is th e ce n ter co nd uc to r will actually move in the diele ctr ic over several years. T hi s usu ally isn 't a big d eal if yo u do n't have any signi fica nt be nds in your RG -8, but does become a p roblem if yo u've woun d a coaxial choke ba lun for your antenna and it's in full sunlight. In tha t case the cable gets ho t eno ug h to so ften up. Many ham s co nsider only th e BELDEN br and o f cables. BELDEN is recogni zed as a quality manufacturer of man y differen t kind s of pro fessional cables and typ ically their prices are high er. Othe r manufacturers o ffer co mpeti ng products and are o ften many times less expensive. In addition to COLUMBIA and TIME cable products, the re are o ther brands that are worth a look. D on't be afraid to co nside r o ther brands to save so me money.

Connectors and jumpers Feel free to use as m any co nne ctors as you want in a feed line the loss is very sma ll. From EE school lab work by Gary Niebo rsky, K7FR, his m easured connect or loss is 0.00 8 dB or less per connector so the only things yo u have to worry abo ut is using th e right co nnecto rs and m aking sure that th ere is no water incursion, which is the biggest factor in ama teur coax failures.

Cheap dBs? What does all this m ean? To a ham with a tribander at fifty-feet, probably not a wh ole lot. Ju st use good coax and enjoy operating. But if you want to improve your signal, you migh t want to dig a little deeper. T he first th ing to consider is to use larger diam eter cable, specifically CATV or other hardlin e. T his will significantly decrease yo ur attenuatio n. A co nte ster and D X'er, Paul Reiter, \W 7I , gave him self

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a boost in RF o utp ut by installing n-ohm CATV hardline up to his antenna. He starte d get ting terrific comments from D X stations abo ut his loud signal and attributes it (correctly) to his reduced transmi tted signal loss (atte nuation) by using th e big hardline. By th e way, he was feedin g a TH7DX wit h a sho rt jumper of R G-8 after leaving th e n o hm hardline. It makes for slightly increased SWR, but th e high er signal and efficienc y more th an make up fo r th e slight feed line impedance mismatch . Free CATV ro ll-ends from your local cable co mpany are always welcome, bu t let's suppose that you are trying to decide if real live A NDREW H eliaX® is wo rt h the investment. Let's also suppose that your run is go ing to be 250 feet from the antenna to the output of your RF so urce. Here are several typical configurations: Cable T ype

Total Loss dB at 30 mHz

RG-213 with PL-259's RG-213 with N connectors RG-8 foam (8214 type) with PL-259's RG-8 foam with N connectors AND REW Heliax '12" with PL-259's AN DREW He liax '/," with N -connectors ANDREW H eliax 7/ 8" with PL-259's ANDREW Heli ax 7/ 8" with N -co nn ecto rs

3.45 3.33

2.45 2.33

1.17 .96 .94 .60

It's o bvio us that the upg rade from RG-213 with PL259's to Yz" H eliaxwith N -con nectors is worth almost 2.5 dBs. Many D X'ers and contesters say th at a 1 dB change is wo rth chasing; th at would m ake this a m ost worthwhile improvem ent! T he next improvement you make to yo ur station might well be to upg rade your feedlin es and take advantage o f the gain (actually red uced attenuatio n) involved . T his is some thing th at will benefit QRO'ers and QRP'ers alike. Of course, th e free cable TV hardline is an attractive alternative. But even if you purchase the coax new, the economics still make sense.

H ardline connectors T here have been dozen s of schemes over the years to use plumbing hard ware or o the r ma terials to fabr icate so mething tha t you can plug a PL-259 int o. Some of the ideas seen seem simple and reliable whi le othe rs are not. If you're goi ng to do it yourse lf, stay away fro m dissimilar metals and make certai n the co nnectio n is wate rproof. Oth-

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erwise my recommendation is to bu y and use th e connecto rs from th e manufacturer. You've alread y saved a ton of money by getting the hardline free, now spend a bit to get som e go od connectors. If you can only afford one, get o ne for th e end out in th e weathe r and fabricate th e one in the shack. That sho uld minimize your potential p ro blems.

Burying coax T here are seve ral reasons wh y you migh t ch oose to go to all th e wo rk of burying your coa x. O ne is th at direct burial cable is virt ually free from st orm and UV damage, and usually ha s low er maintenanc e cost th an cable tha t is out in the open. Ano ther reason might be aesthe tics; a buried cable will be acceptable in almost all communities. Also, being underground doe s a great job of de-coupling the feedline that minimizes inter-station interfe rence as well as RFI. Although any cable can be buried, a cable th at is specifically design ed for direct burial will have a longer life. The best cable to use is one that has a high -density polyethylene jacket because it is bo th nonporous and will take a relatively high amount o f compressive loads. In some direct burial cables, an additio nal m oisture barrier o f pol yethylene grea se m ay be applied under th e jacket; this allows th e material to leak o ut, thus "h ealing" small jacket penetrations. H ere are some direct burial tips: 1. Because th e outer jacket is the cable's first line of defense, any steps which can be taken to pre vent damage to it will go a lo ng way toward maintaining th e internal characteristics of the cable. 2. Bury th e cable in sand or finely pulverized dirt, without sharp sto nes, cinders or ru bbl e. If th e soil in the trench does not meet these requirem ents, tamp four to six inches o f sand into th e trench, lay th e cable and tamp another six to eleven inch es o f sand above it. A creosoted or pressure-treated board placed in th e trench above the sand prior to backfilling, will provide some p rotection against subse qu ent da mage that co uld be caused by digging or driving stake s. 3. Lay the cable in the trenc h with some slack. A tightly stretched cabl e is mor e likely to be damaged as th e fill material is tampe d. 4. Examine th e cable as it is being installed to be sure the jacket ha s no t been dam aged during storage o r by being dragged ove r

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sharp edges. 5. You may want to consider burying it in pla stic pipe which is th en used as a conduit. Be careful to drill holes in the bottom o f the pipe at all low spots so that any mo isture can dr ain out. 6. It is important th at burial is below the fro st line to avoid damage by the expansion and contraction of th e earth during free zing and th awing of the earth, and any water sur ro unding th e buried cables. While PVC pipe provides a mechanical barrier, water egress is pr actic ally guaranteed - you can't keep it out. It'll eith er leak in directly or will condense from moi sture in the air. Use the perforated type so that any water will just dr ain out harmlessly. Here's a hand y refe rence table of coax losses for amateur bands. Thanks to Frank Donovan, W3LPL, who put it together and made it available.

Table 1 . Coax Types and Attenuation Cable Attenuation (dB per 100 feet) :

LDF 7-50 A FHJ-7 LDF 5-50A FXA7 8-50J 3/4" CATV LDF 4-50A RG-1 7 LMR- 600 SLA I2 -50J FXAI2-50J FXA3 8-50J 99 13 LMR-400 RG-213 RG-8X

.03 .03 .04 .06 .06 .09 . 10 .10 . 11 . 12 . 16 . 16 . 16 .25

049

.04 .05 .06 .08 .08 . 13 . 13 . 15 . 15 . 16 .23 .23 .23 .37 .68

.06 .07 .09 . 13 . 13 . 17 . 18 .20 .20

.22 .3 1 .3 1 .32 .55 1.0

.08 . 10 . 14 . 17 . 17 .25 .27 .29 .28 .33 AS AS

046 .75

104

. 10 . 12 . 17 .23 .23 .3 1 .34 .35 .35

040 .53 .53 .56 1.0 1.7

.

. 12 . 15 . 19 .27 .26 .36

. 16 .20 .26 .39 .38

040

.50 .55 .56 .65 .85 .92 .87 1.6 2.5

Al

042 047 .64 .64 .65 1.2 1.9

048

.27 .37 AS

0.5 0.8 0.8

.77

104

.62 .84

1.7

1.3

2.5 1.7 1.9 2. 1 2.7 2.7 2.7 5. 1

.94 1.0 1.2 1.5 1.6 1.5 2.8 4.5

104

804

0.9 1.7 1.5 2.8 3.0 2.5 5.0 3.1 3.0 4 .0 4.9 5.0 4.7 10.0 13.2

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145

Table 2 . Coax Types and Attenuation Cable Attenuation (feet per dB) LDF 7-50A FHJ-7 LDF5-50A FXA78-50J 3/4" CATV LDF4-50A RG-17 LMR-600 SLA I2-50J FXA I2-50J FXA38-50J 99 13 LMR-400 RG-213 RG-8X

3333 2775 2 108 1666 1666 1145 1000 973 909 834 625 625 6 13 397 257

2500 2080 1490 1250 1250 809 769 688 667 625 435 435 436 279 181

1666 1390 1064 769 769 579 556 492 500 455 320 320 3 10 197 128

1250 1040 750 588 588 409 370 347 355 300 220 220 2 19 137 90

1000 833 6 11 435 435 333 294 283 285 250 190 190 179 III 74

.•••

833 667 526 370 385 287 250 244 235 210 155 155 154 95 63

625 520 393 256 275 2 15 200 182 175 150 115 110 115 69 47

370 3 10 22 7 130 161 125 77 106 100 83 67 62 67 38 27

200 165 125 7I

59 70 40 59 53 48 37 37 38 19 14

110 92 69 36 33 39 20 33 34 25 20 20 21 9 8

Table 3 • Coax Types and Attenuation Feet Required for 1 dB Advantage LDF5·50A vs: LDF7-50A RG- 17 FXA I2-50 J 9913

2500 1666 1250 935

1430 1430 1000 590

1250 1110 770 455

9 10 770 525 320

715 560 435 280

••

: .

625 475 355 220

475 420 255 150

279 120 120 85

158 60 75 53

90 30 40 29

Table 4 • Coax Types and Attenuation Feet Required for 1 dB Advantage LDF4-50A vs:

RG- 17 FXA I2 -50J 9913 RG-2 13

-

-

-

-

1430 618

1000 434

2000 715 306

1250 500 2 12

:.

-

-

-

1100 455 171

835 345 146

625 235 106

220 250 135 58

90 145 75 29

40 65 40 14

21 WEATHERPROOFING T he prim ary purpose of weathe rproofing is to keep out mois ture and contamin ants fro m your coax electric al co nnec tions. Whethe r it's rain or co ndensation, water in a co nnector cable can pu t you off th e air.

Electrical tape Every ama teur installation has m any feet of electri cal tape used outdoors in a variety of applications. T he '3 rolls fo r $1' hardware store specials are n o t recommended for demanding outdoor use, particularly for weatherproofing. SCOTCH (f~ I) Super 88 is just about ma ndatory. Besides bei ng conformable to OaF (-18°C), it will perform co nti nuo usly in ambient temperatures of up to 220°F (105°C) and it is UV resistan t. The data sheet says it provides " moisture-tight electrical protection" and it retails in the $4 to $5 range. Another SCOK H tape, Super 33 + , is another "premium grade, all-weather vinyl insulating tape" with many o f th e sam e pro perti es and spe cs as the Super 88. T he o nly differen ce is that Super 88 is slightly thicker th an Super 33 + (10 milsfor88 VS. 7 milsfor 33+). Both tapes are easily

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applied at low temperatures, and will even stick to a wet aluminum antenna boo m . Ano ther spe cialized tape is the SCOTC H 130C Linerless Rubber Splicing Tape. T his is a fairly thick (30 mils vs. 7 mils for Super 33+) tape , is intended for high-vo ltage splices and is moisture-sealing. 3M mak es many prod ucts for dema ndi ng electrical use - th ese are just severa l of them. You may have your ow n favorite.

Weatherproof connector joints Properly sealed connector joints will be very effective an d reliable in maint aining electrical an d me cha nical integrity. H ere's how to do it: 1. Install and solde r th e con nector co rre ctly on th e end of the coax. If you've don e dozen s of co nne cto rs, you know how to do it. If you're no t sure, have someone ch eck yo ur work an d don't scrimp on the so lde r. For the bes t results, you may wa nt to use silver solder on your out door co nn ectio ns. 2. Always use two pairs of pliers or cha nnelocks whe n seating the co nnector to a fem ale 50-239 or barrel co nnector. Hand tight ene d co nne ctions are not tight eno ugh! D o not crimp or de for m the connect or. 3. Apply two wraps of premium elec tric al ta pe (S cotch 33 + or 88). 4. Apply a layer o f vapor-w rap ma ter ial. Avoid CoaxSeal if possible, as it crac ks and dries out as it ages . Do not p ut Coax Seal directl y o n a co nnecto r; the connector will be un usab le once it is rem oved. You will have to cut it off and throw it away be cause the CoaxSeal cha nges your PL -259 into a gooey mess. By putting o ne or two wraps o f tape over the joint first, your connector will be protected from the vapor-wrap and it will loo k as good as new if yo u ever have to take it apart. To remove, simp ly take your razo r knife, slice down the joint and peel o ff th e wea therproo fing. Vapor-wrap is simply a butyl rubber material that co mes in ro lls or sheets and does an excellent job of iso latin g th e joint from the elements. A be tter vapor-wrap is the co mmercial vapor-wrap variety, such as Andrew or db Products. It wo n't stick to connect ors and comes off easily and is handled by Champion Radio Products. 5. Ap ply two or three layers of tape over the vapor-wrap.

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6. When your coax joint will be running vertically, always app ly the final layer of tape in an upward directio n. T his way the tape will overlap in such a way that water will not be co nducted into the tape lap s (like the shingles on yo ur hou se). Tape wrapped downwards will form little pockets that will not only trap the rain but will also conduct it right into your joint. 7. After you've torn or cut the tape, do not stretch it when app lying the final few inches . Let th e Connection tape relax, then attach it. If you put it on under tension, it will "flag" which is the technical name for that loose tape end that is flapp ing around in the breeze. 8. Paint the whole joint with a protective layer; e.g., clear acrylic spra y Tape pai nt. T hat join t should never fail. (Some people like to use ScotchKote Drawing 1:The proper way to but it's meant for buried applications and putthefinal wrap on vertically is not UV resistant so it'll flake off in a running coaxjoint. year o r two.) Cable

Shrink-fit tubing Altho ugh shrink-fit tubing has been available for years, a new wrinkle for coa x joints is shrink-fit tubi ng with glue impregnated along the in side. As you app ly heat to the shri nk -fit, it shrinks wh ile the glue melts and oozes inside between the fitting and the tubing. It not only keeps the tub ing from slipping, but it also fills in the voids in the joint and provide s an additional seal. It's an expe nsive alternative (approximately $1 per inch) but is very simp le to use and remove if necessary.

Feedpoints The feedpoint of yo ur yagi or wire antenna should also be weatherproofed. For commercially made baluns , just use the method s described abo ve. For wires attached to feed points or dipoles, just do the best th at you can. For bare nu t and bolt connections, you can put a little ball of vapor wrap over the connection. T hat'll do an

21 -

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excellent job of weatherproofing it. You'll probably have so me dissimilar metals so I wo uld be sure to use o nly stainless steel hardware and so me type o f appropriate ant ioxida nt o n th e co nnecti on. Also, use silver solder if you have to solde r anything.

Silicon caulking I never pu t silico n caulkin g m aterial (RTV - room tem perature vulcanizing) o n anythi ng tha t need s to conduct electricity, especially antennas or coax joints. Silicon cures by abs o rbing moisture o ut o f th e air. It also releases or outgasses a solve nt m at er ial (acetic acid) during th e curing pro cess. This is th at 'greasy' feeling th at yo u ge t after han dlin g silico n tha t's been curing fo r awhile. What yo u win d up wi th is a connector th at not o nly is ab sorbing m oi sture but also is giving off a so lven t that will migrate into yo ur connector an d cau se it p robl em s- a double wha mmy! If yo u mu st use RT V, use th e aqu arium typ e o r DO\',· CORNING 3 145 RTV Adhesive Sea/alit for best results and reliability. T hi s RTV do esn't have the o u tgas problem.

22 ROTATORS Rotators may be categori zed as one of those nec essary evils som etim es you can't live with the m and yo u can 't live with out them. \'V'hile rotators enable us to turn our dir ectional antennas in a desired headin g, they are frequently the weakest link in many antenna systems. Anytime yo u have an electrome chanical de vice such as a ro tato r, you have a number o f scen arios fo r failure- and usu ally at a most inc onve nient time!

Brakeless wonders At the bottom o f th e ro tato r totem pole are th e "brakeless wo nde rs." These are rotators designed pri marily for T V antennas or lightweigh t amateur array s; th ey don't have a brake bui lt into them . In stead of a brake, the y typica lly have some way of addi ng resistance to ap plied wind forces, such as a co rk pa d. T hese rotators include the H y-G AI N BY T ELEX TR44, CD 45, the YAESU G-450XL and the now de funct A LLIANCE H D 73. Sma ll tribanders and VHF/ UHF antennas are suitable applications for this class of rotator. The lack of a brake means th ey will turn in the wind, but they will give

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reasonable du ty for the price for modes t installation s.

HAM-IV'S and T2X Tailtwisters Larger loads need a rotator with a real live brake to hold the ante nna when the wind blows. T he entry level ro tato r he re is th e H vGAIN HA J\I! I T/. It has a soleno id operated br ake and will ge nera lly hand le big tribande rs or sma ll stacks. Its bigger bro th er, th e T2X Tailtndster, is a ph ysically stro nger ro tator for a large r dollar investm ent. T he add ed strength o f th e T2X comes from larger bod y castings, and it also contains more ball bearings to acco mmoda te heavier loads. Interna lly, the parts are th e same for both the HAlv! IV and the T2X; same motor, same gears, same almost everything. T he good news is tha t th e HAlv! IV / T2X have becom e the de-facto standards fo r American ham s. T his means all towe rs are built for their bo lt patt ern . T his also means part s are read ily available and you can even m ake repa irs yours elf. And th at means you can find them just about everywhere, including your local ham radio flea market. T he bad news is th at the weak ne sses and fixes for these rotators are well docume nted; e.g. indicator po tentiometers and brakes. T hese rotators are ve ry sensitive to voltage drop so be certain to use th e recommended wire sizes or put up with the resultant problems. An eme rgency first aid kit for these rotators sho uld include a few fuses - th ere are two - and a spa re motor starting cap acitor.

O ther ro tators Hy-Gain also ma nufactures th e H DR-300. T his is an o ff-theshelf transmis sion with a 1 rpm motor. Hy-G ain adds the brake and indicato r/ co ntrol system and you get a medium d uty ro tator with a co up le of limitations; th e splined o utput shaft and th e brake effectiveness are both troublesome C ra ig Hen ders o n , N8 DJB (www.ro to rdo c.co m). is o ne of the leadin g H y- G ai n rotator rep air g uys in the coun t ry. Afte r fixing h undreds o f them, h e has co me o u t with hi s own ro ta tor - the CATS RD -ll 00 . It's we ll engineere d , ro bust and h as a smaller footp rint tha n t he T2X, m a king it suitab le fo r Rohn 25G in st allati on s. Mike Staal, K6MYC, through his co m pany M 2 ANTE N t\S , pro-

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duces the 0'7011 OR-2800 rotator. It feature s a wo rm gear de sign and a digital control box with pr eset s and computer interface. A large antenna system, such as a stack of monobanders, is a candidate for an O rion. This is a simple, power ful ro tator but has a user unfriendly control box and th e mast clamp has 2 fatal problems - clamp teeth th at only give less th an an estima ted !f2 sq. in. o f mast contact area and dimpled fastener surfaces that eventu ally flatten out, permitting the m ast to slip. These two design flaws will let th e clamp loosen up . In my almos t 20 years o f tower wo rk I' ve in stalled dozen s o f th ese rotator s and virtually 100% of th em loosened up ove r time . T he TIC G ENERAL Ring rotators have been out for over ten years and offer a unique solution to the problem o f turning an antenna aro und a tower o n a side mo unt. They have not yet established themselves as the ultim ate answer to sidemounting antennas. A recent entry in to the side- m o un ted rotator cat egory is the O rbital Ring Rotator by Rich Bennett, KOXG (www.KOXG.com). Like all of his p roduct s, it is a very ro bust de vice with a large capacity. Re ce nt entries in th e rotator market in clude the AlfaSpid an im p ressive little ro tato r with a worm ge ar drive imported from Poland - and the P ro sist el lin e o f Big Boy worm ge ar drive rotators manu fac tured in Italy that ha ve m edium to h eavyduty capacity.

Japanese rotators J ap anese ro tato rs are impressively designed and manufactur ed, and have made a den t in the US mark et. They seem to suffer fewer probl em s in the reliability area co mpared to o the r rotators, however repai r and part s availability has been the ir weakn ess. Anothe r min or dr awb ack is th at you need me tric tools to work o n them. Altho ugh the self-centering clam sh ell mast clamp that m an y o f th ese rotator s use is an inn ovative design, most o f them are made from cast aluminum pot metal and can be easily broken durin g no rm al installation. YAESU, E lI fOTO and CREATE rotators were all im po rted from Japan, bu t the Yaesu are th e onl y o nes currently available. T he Yaesu s have establi she d themselve s as reliable rotators with nice analog contro l bo xes, an adj ust able pre set on most models, and a rotation ov erlap that gives 450 degree covera ge.

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Prop pitches Many serious antenna systems have been built around prop pitch rotators. Having an incredible 9,576 to 1 gear reduction and built to military specifications, prop pitch motors have proven themselves to be reliable as well as rob ust. T hey are the tran smissions from propeller driven aircraft and primarily from World War II. T hey were the mo tors that changed the pitch of the propellers and are behind those round cans that stick out of the middle of the propellers. Many have been up for twenty years or more and are still o perating. T he biggest problem th ese days is that the sup ply is dwindling. You won't find th em at every ham fest anymore but th ey are still available if you go looking. \x?ith the decreased sup ply comes increased cost. When you co nsider the alterna tives, an investme nt of $1,000 or mo re in a prop pitch doesn't seem out rageous. Co nside ring what other new heavy duty rotators sell fo r, you can get a rotator that will turn your hou se if necessary and will last fo r years fo r about the same amount of money. Nothing else comes close. With a prop pitch, you'll have to sup ply the power and the directional indic ato r. T he power is fairly easy; you need 28 VDC at at least 10 amps. Although 28 VAC can be used, D C is much easier on th e motor. You can use 14AWG or similar wire with little vo ltage drop (no t a big deal with prop pitches); simply use th e th ree wires fo r left and right rotation. Be sure to pu t bypass capacito rs o n the brush leads or you'll have your own spark generato r trashing th e band s every time you turn your antenna. The indic ator problem also has an easy solutio n. Altho ugh it's impossible to get a prop pitch at a flea market for under $100 anymore, you can still get selsyns for $5 and less. A selsyn is a m echanism consi sting of two units connected by wires whe re turni ng o ne o f the two will turn the o ther one th e same amo unt. A fter you've found a co mpatib le pair (sam e nu mber of wires with same vo ltage and co nnections), fabricate a mounting arr angement that will secure the tower selsyn close to th e mast. Mo unting it up side-d own will pre vent water from running down th e outp ut shaft into th e selsyn itself. H ose clamps will be quite handy for thi s part of th e operation. You have two cho ices fo r coupling the selsyn to the mast. O ne method is to have two identical gea r sprockets; one on th e ma st and the other on the shaft of the selsyn. The onl y tricky part is ge tting th e

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sprocket around the mast. Another way is to mount a pulley onto the selsyn shaft that is the same diameter as the mast. T hen all you need to do is put a be lt of some sort around both of them. I've seen long spr ings used, as well as good sized fishing line, to provide the linkage. Anothe r op tio n is to use a small belt o f some kind. As long as it is fairly impervious to weather and UV proof, just about any arrangement will work. Rather tha n fabricating yo ur ow n controll er, the G reen Heron RT-21 will wo rk with virtually any rotator and is also user friendly. It is co mpute r co mpatible and has many nice features. An easier way to use a prop pitch is to buy one all read y to from Kurt Andress, K7NV Hi s work is gorgeous an d it comes complete an d ready to use . A Green Heron co ntrol box and custom mast clamp are also available. www.k7 nv.co m

Rotator loading Rotator manufacturers have found that th e square footage o f an an tenna doesn't accura tely reflect th e load s placed on a rotator. •

Rotator Create RC5- 1 Create RC5- 3 Prosiste l 641 D Hy-Gain Ham IVN CA T. S RL- I I00 Yacs u G-8 00 Yaesu G- I000 Hy-Gain Ta iltwister Prosistel 205 1D Alfa.Spid RAK (ii ' 12V Create RC5A-2 Crea te RC5A -3 AlfaSo id RAK (a; 18V Creat e RC5B-3 Pro sistel 6 1D Yae su G2 800D XA M2 Orion 2800 AlfafSpid RAK (ji) 24V Hv-Gain HOR 300 AlfaSpid Big RAK (iiJ 12V T IC Ringrotor 1022 0 (I motor) Prosislel PST 6IDHP T IC Ringrotor 1032 D ( I motor) Prosistel 71D AlfaSpid Big RA K (iiJ 18V T IC Rinarotor 10220 (2 motor s) T IC Rinurot or 10320 (2 motors) Sma ll oroo Ditch

I

•

I

•

I

I

'

Rotating Torque, in.-Ib. 500 500 570 800 800 950 950 1000 1255 1400 1400 1400 1800 1910 21 50 2 170 2800 3240 5000 5000 6500 7640 788 1 7980 > 8000 11,500 13,467 16,000

6000 6000 3 135 5000 4000 3450 5200 9000 7 125 14,000 13,000 13,000 14,000 17,000 16,530 2 1,700 17,000 14.000 7500 24.00 0 6500 16,530 7530 30,400 24,00 0 6500 7530 Unk nown but robust

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T he pro blem is tha t a squ are footage figu re doesn't rep resent th e to rq ue o r ro tating m oment . Two antennas with the sam e surface area could put dra stically different loads o n th e rotator. As a result, two rotator manu facturers have come up with their own me th od o f calculating ro tato r loading. H y -GAI N uses a measur em ent called "Effective Mo me nt," which is defin ed as th e pro duct o f an antenna's weight (o r mass) and its turn ing radi us. Yr\ESU'S "K-Factor" is the same as the H y - G AI N "Effective Moment." Us e this calculation to more acc urately select th e proper ro tator for your installatio n.

Rotator torque Wh ile the above rotato r ratings have to do with antenna wind loading, the rotator must have sufficient sta rting to rque to start th e mast and antenna system int o rotation . It mu st also have sufficient braking to rque to hold th e an tenna in the wind .

More nuts and bolts It's p robably not sur p rising th at m o st rotator failure p ro blem s are ca us ed by ove rloa d ing. Big win ds p rodu ce big forces on the whole antenna system; a lo t of these force s travel down the m ast to th e ro tator. Pe op le as k if th ey sho uld pin thei r rotato r th rough the ir mast w ith a lo ng bo lt, to p revent the m ast fro m turning in the rotator d ur ing a wind storm. W hat happens if you do is th at now yo u' ll find the n ext weak point in yo ur syst em, and it's usua lly an internal gear or p ar t. T he Yaesu ro tato rs do co me with a bo lt for pinni ng the mast while other manufacturers say that pinning the mast will vo id th e warranty so use yo ur best judgment and experience to decide whether to do it o r no t. By the way, if the wind does turn yo ur antenna o ut of alignment, simply point th e antenna when it's parked in a direction such that the next winds to rm will blow it back int o alignment. You know what you r p revailing wind direction is, just use the wind to put your antenna back where it belongs.

Thrust bearin gs T he purpose of a thrust bearing is to bear the ve rtical and horizontal load o f the mas t and antennas of the syste m. Use o nly

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o utdoo r rated thrust bearin gs. You'll recogni ze th ese as being galvanized or made from alum inum . Do not use any bearing made for ind oor use, such as machinist pillow bloc ks or wheel bearings. Generally, do not use any bearing that uses a single Allen screw to secure the shaft. The Allen screw and the bearings will ru st and seize in a few sho rt years and you 'll have a stuck antenna system and a genuine rep air problem. If you're no t sure, just leave th e bearing o ut in the backyard for a few weeks and see wha t happens . If no rust appears, you can probably use it. If you do get ru st spots, throw into the recycle bin. This will save you a lot of future ang uish .

A word of warning There is one primary rul e when it comes to ro tato rs; never install a rotator th at is more th an five years o ld without having it inspected and refur bished. If all you have to do is grease th e bear ings, you'll still be doi ng yourself and your rotator a favor. Any o lder rotator is a time bomb waiting to go off-and fail. D on't believe the guy at the flea market wh ere you bought it who to ld you it had just been " rebuilt" . G o thro ugh it yours elf or have so meone capa ble go through it. D on't say you haven 't been wa rne d! Rotator destruct test Back in the 90's I was worki ng at the H y-G ain factory in Lincoln, N E, and we h ad a customer th at wanted to k now h o w mu c h b ending st re ss a Tai lTwister (T 2X) wo uld take, so we pu t one in the lab an d found o ut. T he dra wing shows th e test set up, an d it wen t to 3,000 foot- Ibs. before th e rotator neck broke. That's a lo t o f force.

Dynamomett:r

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Ca5tfng vrok"c at

t he point indicated at 1000 pconao

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appliea lo. a.

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10 00 L~.

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Drawing 1: Hy-G ain lab destructtest lab set-up.

23 INSTALLING BEAMS After you've invested a significant amount of time, en ergy and mo ney putting up your tower, ne xt comes the challenge of getting your new flameth ro wers mo unted on the top of th e installatio n. Big yagis are a handful, w hethe r th ey're o n the gro und or up in the air. Installing them o n a tower can be a long and arduous undertaking. \X!hile there are vario us ways to rig an anten na for hoisting, two meth ods are normally used.

Sling rigged Once again we use our old frien ds, th e nylon slings as chokers. I prefer to use long slings (six-foo t or m o re) fo r rigging the boom. In stall o ne sling o n each side o f the center mou nting point of the antenna wit h two or three wraps around th e bo om; th en bring them together so that th e pick point is righ t above where the boom plate will attach to th e m ast. T his assures that the antenna is balanced and will arrive in the co rrect mounting positio n. Us ing two slings on the boom enables you to hoist the beam up int o p osition hori zontally. Even if th e ant en na is mec hanica lly o ff balance, you can adjust the

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slings so that it will remain basically horizontal. With antennas that have the elem ents mou nted above th e boom (such as M 2 and SteppIR) , th e antenna will attempt to "turtle," or flip ove r, if given the cha nce. You can minimize that tendency by tying the slings with opposite wraps (one around the boom in one direction, th e othe r wrapped in the othe r direction).

Lifting torque arm A lifting torque arm (LTA) is a long plate which attaches vert ically to th e boom of the antenna with U-bolts and is the attachment point for the haul line. The long (18 to 24 inches) size of the LTA act s as a torque arm to keep the boom horizontal. T he longer the LTA, the mo re torque it will exert; also the more clearance you'll need up at the mast in order to get it into position. T he main dr awbacks of the LTA are that the LTA will be offset from where the boom mounting plate is (a ma jor hass le if you're the person on the tower that ha s to w restle it into place) and it doesn't do a very good job with an o ut -of-balance load. A similar device is called a tiller. It can be shorter than the LTA and extends parallel up the tramline. T he upward end of it slides along the tramline via a carabiner or other clamp thus ho lding the beam in a pre-determined attitude, typically where the elements will clear the top gu ywires or any other potential obstructions. It can be as sim ple as a 2-4' long piece of angle U-bolted to the boom.

Hoisting the antenna Unless otherwise noted, the boom of the antenna should always be horizontal when lifted. The " dead lift" is simply pulling the horizontal antenna straight up the tower. On a self-supporting to wer, thi s is the easiest way to do it. With a guyed tower, you can spend a lo t of effort threading the antenna thro ugh the guy wires , a technique Tom Sch iller, N 6BT, describe s in his book ''Array of Light" th e "wig wag" technique. It brings the antenna up horizontally but then threads it through the gu y wires. This is very useful where you don't have enough room for a tramline system or have som e other limitations. I use it occasionally an d it's a nifty alternative. Another varia tion is the "boom vertical dead lift." This is also a lo t of work and you must still thread the antenna through the guys.

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Also, you must tip the antenna back to horizontal o nce it's up to its mounting pos ition. I've never used this technique and it certainly does have its limitations. Another option is to assemble th e ant enna at th e top or on the tower. For large arrays, this can be quite useful, particularly if you can pivot the bo om during assembly. Again, th is involve s a lot o f wo rk - let's face it, the y're all a lo t of wor k! - and a special antenna mount th at will allow th e antenna to pivot. Fo r som e installation s, " skyhooks" may be the only practical solution. T hes e are typically th e m ost dollar intensive. Cranes with 140-foot jibs can co st $150 or more per ho ur. Helicopters can be just th e ticket for some in stallations. They run aro und $500 per hour in th e Pac ific Northwest but can often accomplish a very diffic ult installation quick ly; the y can thus become cost effective. Two things you must keep in mind when working with helicopters; their down draft creates a terrific amount of static electricity; you'll need so me way to bleed o ff th e charge or you'll ge t zapped. It's not dan ge rous bu t it's a jolt. Also it onl y takes around fifteen-p o un ds pressure to mo ve a chopper. Rem ember, it's in equilibrium when it's hovering and it doesn't take mu ch to m ove it. Just grab the load and pull it to where yo u want it. Left, right, up, down-it's an easy maneuver. An exciting maneuver, but an easy one. H ot air balloons are also used occasionally with so me success, but can pres ent problems o n days tha t are not virtua llywindles s.

U sing a tramline In my opinion, tramming is usuall y the o nly way to go. A tram system is where the load is susp ended below the tramline and I use it for m ost an tenna raising projects on towe rs, and even on trees. This is not the technique tha t uses two ropes stretched out parallel with th e ant enna sitting o n top of two lines running fro m the groun d to th e tower - tha t's th e trolley technique. That method is a real head ach e; th e ropes are diffi cult to equalize and th ey'll oscillate, the beam gets real tips y as yo u get to the to p o f the tro lley lines and there's a lot of dra g resistance as you pull the antenna up th e rop es. This is a method to be avoided! My prefe rence is to use one steel tram line with the antenna suspended below th e tram wire. You'll need three pulleys, a haul line,

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r- ------ --- - ------- -- --D~tail

#1

-----A!

D~tail#2 f --- --- - - - - - - - - - - - - - - - :> in the subject and yo u'll be all set. O ver 13 years wo rth o f archives are available at www.contestin g.com. I don't think th ere's a single towe r or an tenna topic th at hasn't been co vered! Two books that'll help yo u mak e antenna de cisions are th e vertical and yagi co m pariso n rep orts available fro m Champion Radio Products (www.cham pionrad io.co m) . Bo th were written by yo ur author and H . Ward Silver, NOAX, and feature o n-the-air compariso ns alo ng with the testing protoc o l. They are HF Vertical Performance - Test Methods & Results and HF Tribander Perfor-

mance - Test Methods & Results 2nd Edition . T here are a bunch of othe r valuable antenna books available for any frequency or co mplexity. Ad d th em to yo ur libr ary. And o f course the Rohn catalog is invalu able . It gives yo u ma ny enginee ring drawings and specificatio ns and asso ciated hard ware. It's availab le online - www ro hnnet.corn - as well as o n CD.

26 BE KIND TO YOUR T REE S /!J' D oug Brede, If/'3A S

If your tree- supporte d antenna fell down, you'd care. D id you ever think about caring for the tre e that holds up yo ur antenna? Fo r most hams, tr ees are favorite antenna sup po rts. Many radi o ama teurs begin their o perating caree rs by hanging the far end of a wire up in the family's shade tr ee. On Field Day, resourceful ham s find a hundr ed and one ways to get an aerial in to the air; man y (if not most) o f th ese m ethods involve using trees as sup po rts o r aids. D urin g my twenty years as a radio amateur , I' ve used treesup po rted wire antenna s almost exclusively. Some of th ose an tennas lasted several years; most didn 't . Over th e years, by trial and errorand becau se o f my tra de asso ciation with arborists and horticulturists- I've gained an understanding o f wha t can (and can't) be expected o f trees as antenna supports. T he re are right and wrong ways to attac h and maintain your tree -mo unted skyhooks ove r th e long haul. I'll share with you so me pointers from two noted horticulturi st s who talk abo ut atta ching wires to tre es. Safety is also discu ssed- your safety during antenna

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install ation, and the safety of the tree.

Trees are alive Few antenna sup ports can be classified as life forms. Trees are an exception . Tree experts usually cringe whe n so meone bri ngs up th e idea o f att aching a wire to a tree-especially wh en connecting a chunk of wire to its midriff. T he experts know that tree s are made up o f three basic layers: the bark, th e living sapw oo d, and th e nonli ving heartwood. The bark p ro tects the sapwood from injury. T he sapwood contains th e "s kin and blo od vess els" o f the tree. If the ster ile barrier between the bark and the sapwood is broken , infection can set in . Infection, if unchecked, can kill eve n a migh ty oak within a year. Tr ees have the same ba sic problems with infection as we humans do. If a tree gets a cut or gash, infection from bacte ria and fun gi is bound to set in. Bu t th er e's o ne imp ortant differen ce b etween trees and humans: "Tree wounds don't heal," says noted tree expert Dr Alex L. Shigo. " Peo ple heal; when you Drawing 1:Attaching ropes or are wo unde d, yo u have forces that fight wires totrees can sometimes off the infectio n. Trees don't have th ese lead tomajor problems forthe forces to fight o ff infection, and every tree. Wrappinga rope around a limb ortrunk and leaving it unwo und will become infected." attended will suffocate the Shigo, autho r o f the book Tree treeand cause a distortion of Biology and Tree Care and man y o the rs, growth orthe death ofthe limb. notes th at tree s lack an immune system tha t fights o ff in fectio n from wo unds tha t occur from th e actio ns of a careless climber or the atta chment of an an tenna-support eyebolt. Trees trea t th eir wo unds by walling off th e in fect ed area and isolating it from the living part of the tree. " If yo u cut ope n a tree that's 2000 years old, you'll see every injury in that tree th at occurred over its lifetime," says Shigo. \X1hen ever you wo und a tree, yo u weaken the tre e in that spot. The walled-off wood aro und th e wound lacks the strengt h of health y

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wood. When attaching an antenna to a tree, it's impor tan t to traum atize the tree as little as possible. T his will ens ure a strong, enduring connection. Most people be lieve that tree paint or shellac is the best way to treat a tre e wo und. "Not so," says Shigo . "Wo und dressing paints just protect the microorga nisms ." Scientifi c research with tree-wound preparations have failed to show any benefi t to the tree .

Maki ng th e attachment Although it's relative ly easy to get a wire up into a tree, it's certainly mo re diffic ult to keep it th ere for th e long term . Us ually, annual (som etimes weekl y) restringing is needed . It seems that tree s "instinctively know" just when to drop a wire to the ground: during midwinter when the snow is high and the skip is lo ng, or in th e middle of a heat ed contest! The bow-and-arro w method has be co m e a standard of the wire -in-the-tree crew. But many other m ethods, slingsho ts, for exampl e- even at taching a string to a golf ball and whacking it with a sand wedge-are common. One o f th e easiest and most common ways to connect a wire to a tre e is to throw a rope over a bra nc h crotch, then tie off the loose end. This is th e main method used in tem porary (such as Field D ay) installation s. "D oing this probably won't hurt the tree if it's done as a temporary thing," says Washingto n State Un iversity horticulturist Ray Maleike. Bu t with any o f th ese I, ,; simple ante nn a-stringing metho ds, so me problems for the tree (and the antenna) may develop later. Drawing 2: Most hams install tree" First of all, you're no t stamounted antennas by throwing a line bilizing the ant en na very well with over a branch crotch. This should be this type of setup. The othe r thing used only asa temporary installation, is th at people have a tendency to because abrasion oftherope and tree fo rget th e an tenna 's there. As the results. Over time, girdling may occur tree gro ws- as it increases in di- leadingto theloss ofone ormore ofthe amete r- you can girdle the tree. branches.

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If you've got this girdling ro pe o r wire up there, yo u can act ually kill that portion o f the tree above th e wire ." Ano the r no-n o whe n atta ching an antenna to a tree is wr apping a wire aro und th e tru nk. T his stra ngles th e veins in the sapwood the same way a noose around your neck wo uld stra ngle you. " It's importan t not to wrap anyt hing aro und the tru nk," says Maleike. Many commercial nurse ryme n wrap stabilizing ropes around new ly tran splanted saplings to keep them fro m falling over. Recently, however, this practic e has been questioned becau se of the restrictions these ro pes place o n the growth of th e tree . People forget about these ropes; some rem ain on tre es fo r years afte r tran splanting. E ncasing th e stabilizing (or ante nna) wir e in rubber o r plastic hose is not the an swer eithe r. "Wire wrapped in hose is just as injurious to the tree as th e bare wire itself," says Shigo. " If you remember your basic physics, you're ap plying the same number of pounds of force to the tree with o r without the hose." Shigo recommends that if you must wrap som ething around the tru nk o f a tree, use a wide fabric strap to do the job . Two methods have eme rged among leading horticulturist s as th e pr eferred way to attach a wire to a tree. For light ante nna loads, such as the end of a dip ole, a threaded eyescre w is the method of ch oice. Just drill a hole int o the oboet 1/ 2 inch tree about 1/ 1('"smaller th an th e allowed for rowth screw diam eter, then twist in the 9 eye-screw. Be cer tain you use a ca d mi u m -p la te d eye -s c rew (AI threa de d for use in wood . A thread length of two o r three inch es should secure most ante nnas. Allow at least 1/ 2" of space between the trunk and 181 th e eye; thi s allows for o utwa rd growth of th e tree with time. Drawing 3:The best way tosecure awire Fo r stouter antenn as, toatree iswithaneyescrew mounted into s u ch as multiel em ent w ire thewood (A).As thetreegrows and exbeam s, another m eth od for se- pands, however, the eyescrewwill become cu ring wires to tre es is recom- embedded (B) and must beremoved and m ended . Thi s proc ed ur e in- replaced.

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volves using an eyebolt lo nger than th e tree diameter, drilling completely through the tre e, th en securing the eyebolt on each side of the tree wit h round washers and nu ts. Drilling a hole through a tree causes much less trauma to the tree tha n wrap ping so mething around it. Much of the core of a tree is dead tissue , used mainly for physical support. Alt hough there will be some wounding of the tree at th e site o f the bolt S te rile Barner or screw, such wounding will be far les s th an that which occurs from wrapping a wire aro und the trunk. O ver time, either typ e o f eyescrew connection will have to be re Flo t placed . "If the se fasteners washer are left on the tree for a long tim e, th e fastener will Drawing4:For heavy antenna loads, aneyebolt eventually beco me emb ed- passed through thetrunk orlimb will support ded in th e tree ," says more weight than aneyescrew. Allow about 1/ Maleike. "You're going to 2 inch ofplay between thebolt and trunk orlimb. Don'ttighten thebolt completely; this allows have to pull these fasteners for tree growth. out and rep lace the m ever y now an d th en ." Ma leike recommends rep lacement o f tree eyescrews ever y five to eight years as the tre e matures. Co mmercial arb ori sts use drivefasteners for securing wires to trees; dr ive fasteners are similar to eye-screws. "These faste ners keep th e wire away from th e tree, allowing the tree to grow out to it," says Maleike. Drive fasteners are used for securing lightning rods and their acco mpanying wires to tre es. The use o f drive fasteners is common in the Midwest, where lightning strikes to trees are common. You may have to sho p aro und to find driv e fasteners-try calling tree-care serv ices in your area. It's easier to periodically serv ice a tree-supported antenna if a pulley is used. Raisin g and lowering the antenna for repairs can be done without the need to climb th e tree each time . I use a flexible truck tie-down to provide ten sion to th e ant enna .

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Your safety in trees A fall from a 40-foot tree is just as dangero us as a fall from a 40-foot tower. Yet, many times you see hams scaling trees with no safety equi pment! Wear a tower-climbing safety belt for all tree climb s. Commercial ar borists take the matter of safe ty one ste p furt her: They lob a ro pe over a tree cro tch just above th e heig ht at which

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~"",~Pulley

\

Atta ch antenna 10 pull ey rape

Truck T ie - Down

Drawing 5:Byusing apulley, raising and loweringthe antenna forrepairs can be done without theneed toclimb thetree. Aexible trucktie-downs can beused to applytension tothe antenna.

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the y'll be working. Then they tie the rope to th eir safety belt. T he lo ose end o f th e rope can be held by a helper o n the gro und . Be sure to use a good quality rope th at is strong eno ugh to sup port your weight. Before use, insp ect th e rope for wear. Arborist s prefer to use hemp ro pe rath er than nylon, because hem p ro pes stre tch less. \X1hen you're climbing a tree to atta ch a wire, always have a buddy on the ground availabl e to fetch to ols or summon help in an eme rgency. Be sur e your buddy wea rs a hard hat; tools or br anches dropped fro m even a mo derate height can b e dangerous. As an alternative to doing it yourse lf, co nside r pro cu ring th e assistance of a professional to install your tree antenna. A professional can clear away interfering branches and secure an eyescrew in sho rt or der. Professional tree trimmers generally work in pairs. They use a ladd er or bucket tru ck to get up into the tree, and then they free-clim b thro ugho ut the tree . A safety rope, saddle, and safety belt are worn. ''A figure tha t I heard about how m uch this runs is about $50 an ho ur," says Maleike . Most tree tasks can be done by profession als in about an hour.

Summary Keeping your station in go od operating conditio n is-or should be-a fun da mental practice o f every rad io ama teur. Part of that practice includes annual inspec tion of your ante nna syste m. If trees are a part of your antenna system, take a good loo k at them. Are yo u keeping the m hea lthy?

SOME QUESTIONS AND ANSWERS ABOUT TREE ANTENNAS Q: A CBer in my neighborhood cut the top out of his pine tree and stuck a ground pla ne antenna up in it. Is this an acceptable way to mount an antenna?

A: Definitely no t. Not o nly is this a hazardous wa y to mo unt an antenna, it essentially ends the use ful life o f th e tree. To pping of tress is str ongly disc ouraged by professional arborists. Because topping remo ves the growing point o f the tree, th e tree recovers fro m the

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da mage by sprouting num erous lateral buds aro und the top, which soon overrun the antenna.

Q : I've heard that if yo u ferti lize a tree, your an tenna will grow higher each year. True?

A: False. Although fertili zing is a des irab le wa y to keep your tree healthy, it does no t raise the heigh t of your attached antenna one inch. Trees grow by extension of the ape x. A wire attached to the trunk at 30 feet will still be at 30 fee t 10 years later. By the way, when you fertilize your tree, use regu lar gar den fertilizer distributed aro und the drip line of the tree. The fanc y tree spikes yo u see advertised are unnecessary because most tree feeder roots are near the surface.

Q: Is there a way to slow down the growth of a tree so that it doesn't interfere with my anten na ?

A: Some home-and-garden stores now stock growth regu lators for trees. These products can be in jected into the tree , dropped on the soil surrounding the tree, or sprayed on the leaves (follow label directions) . Tree professionals can also perform this ser vice. T hese growth regu lators are used by some utility companies to red uce the need for tree trimming near power lines .

Q: Are certain types of trees better wire-antenna supports than others? What about hardwo od versus so ftwoo ds? A: There's little difference between hard- and softwoods in their ability to hold up antennas. Co nifers, because of their shape, are nea rly ideal antenna supports. Avo id the use of red oaks and silver maples, if possible, because the y ten d to rot easily if wo unded. Avoid using poplars, too. In spite of their heig ht and rap id growth, their branches are brittle and break easily.

Q: If I damage a tree du ring antenna installation, what should I do? Is tree replacement expensive?

A: If the damage is minor, your best be t is to do nothing. If it's a bro ken lim b, saw the limb off cleanly, pe rpe ndic ular to the axis of the branch . N ever saw off a branch flush with the surface of the

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trunk, as this allows decay to set int o the trunk. Us ing tree paint fo r injury rep air is unnece ssary (see text). In case of major tree damage, consult a trained arborist, The answe r to th e sec o nd question is: Yes, tre e replacement is expensive. T he Internatio nal So ciety of Arbo ricultu re publishes a formula for calculatin g rep lacement co st of shade tre es of vario us sizes. Thi s pamphlet can be o btaine d fro m man y tree services an d libr arie s. H ere's one point to ponder: A large, stately shade tr ee can add several tho usand dollars in value to th e property on which it sits.

Doug Brede is a[ormer Associate Professor if H ottiadtnre at Ok lahoma State Universi0' and is noiu research directorfor a lIlajor nest-coast seed COIllPal!J. H e has turitten more than a hundred technical articles on landscape topicsfor lIlagazinesill the lalldscapillg illdustl)'This article nias origillall;'printed ill OST, Septelllbelj 1989, and is used Ivith permission.

27 TREE INSTALLATIONS

In many part s o f the co untry, tr ees offer usab le, cheap ante nna sup po rts. Co nifer s such as pines o r firs, being single-trunked, are ideal fo r use as an tenna supports, while multi-trunked maples and cottonwood s are almost impossible to climb o r use. In gene ral, trees are not regu lated, nor subject to building cod es or permits. T here hav e been three instances in \X!ashington State whe re am ateur tree installatio ns have been challenged (initiated by overzealous neighbo rs) by b uilding dep artments: in eac h case it was determined th at the antenna in a tree was no t sub ject to any building dep artm ent regulations. A tree is a tree is a tree!

Wire antennas Yo u'll need two tre es, o ne fo r each en d o f yo ur wire an tenna. I t's very difficult to install an inver ted vee in a tree b ec au se it's just about im p o ssibl e to get b oth sides of the antenna th rough th e branche s. For attaching wire an te n na s, find a p rofe ssional tree climber / arborist in the YelloJJJ Pages o r a talen ted buddy to in sta ll a pulley and rope syst em in yo ur trees o f ch oic e. A 3/8" o r Yz" eye

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lag bo lt screwed in to the tree with a pu lley attached is the b est method. U se a chain link o r co ld shut to attach th e pulley to the lag screw eye. I prefer a non-swiveling pulley because the lay o f th e rope can cause the rope to turn and twi st together an d possibly jam the pulley. U se only metal pulleys; preferabl y o n es made fro m stai nless or galvanized materials. Plastic p arts will either break o r be damaged by UV radi ation. Ch eck yo ur loc al hard ware sto res for usable p ulleys; cheap stainless steel ones lo cally are avai lable for $5 to $10 each . K eep in mi nd that with pulleys and ha ul ro p es there should be min im al clearan ce be tw een th e sheave and th e pulley body; th e rope sh o uld b e larger in diam eter than the clearance so that it can't ge t jam m ed in the pulley-a m ajo r anno yance. I u se 1//' polypropy lene rope; only a v ery sloppy p ulle y wi ll allow it to jam. A m uch better option for yo ur rope h alyard is black dacron UV re sistant lin e. Have yo ur climber go up the tree un til he re aches a su itable spot, then screw in the pulley. I t's all but certain th at the tr ee will have to b e p ru ne d to clear a dec en t window th rough whic h the lin e can trave l. It's better to over- p r une since n ew g rowth will inva riably g row into th e spo t in ju st a few years. Sma ll branches are incredibly stro ng and resilien t and can cau se major problems in any tree p roje ct o r in stallat ion; they'll even p revent a yagi from turning. H avin g b rought the lin e up with him, the clim b er will put th e lin e th rough th e b ack side of the n ewly in stalled pulley, attach a we ig ht to th e end of the line, th en throw it o ut in the direction th at yo ur wi re anten na will take. T he wire antenna mu st clear all branches to successfully install your antenn a. Wh en th e end o f the line reaches the gro un d, rem ove th e w eigh t, the n tie the en ds o f the lin e together, m akin g a loop. T his is be cau se in almost all cases it is th e antenna that bre ak s, not the halyard. Witho ut a loo p, wh en th e ante n na breaks the end o f yo ur hau l lin e will b e at the to p o f the pulley and yo u' ll have to send so meone up to re trieve it. If yo u have a lo op system , all you h ave to do is pull yo ur line down and rea ttac h your wire an tenna. Ti e an overha n d kno t for yo ur wire attachmen t point wh ere th e ro p es ar e tied togeth er and yo u 're read y to start h oi sting.

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Up TH E TOWER

If yo u're go ing to climb th e tree yo urs elf, you' ll ne ed sturdy boots, hardhat, a safety belt with two lan yard s and tree climbing spurs. You'll need th e two lanyard s to leapfrog your belts aro und branches so th at you'll be belted in 100% of th e time. In a strong wind that will get yo ur trees swaying, yo u'll want to have a method that allows the trees to move without bre aking th e antenna. You can use a weight of so me sort (cement block, plastic milk-container, a bucket wit h rocks, etc.) or use a rub ber bungee cord (or truck tie-down as mentioned in the pr evious chapt er). Newer tre e climbing techniques don't use stee l climbing spikes as it's deemed harmful to the tree. The latest meth od s use a line th ro wn o r sho t over a branch and the n the ro pe is used to climb the tree using ro pe asce nde rs like the ones used by mountain climbers. You don't even touch th e trunk of th e tree using this technique so it's pretty benign . There are slings ho t-type devic es as well as co mp resse d air gun- types th at you can use to ge t the line over a branch as well as the bow-and-arro w technique. Tree climb ing has even beco me a recreation al activity sim ilar to th e way th at ro ck climbing has. There are club s and reso urces available and you can find a lot of th em o nline. Be sure to chec k o ut the equipment and techniqu es and you can do this yourself.

Preparing the tree Mos t tree Yagi in stall ati ons require an un ob structed m ounting at the top of th e tree. In other w o rd s, th e top o f th e tree n eeds to be rem oved , or to pped. While arb orist s disco ur age tree topp in g for sev e ra l rea so n s, in the Pacific No rthwes t m an y h om eown er s do it as a matter o f course to reduce th e size o f a tree and it s ch an ces for b eing bl own do wn d ue to a wi nd storm . Topping the tree, unfortunat ely, can't be avoided. My adv ice is to be as ge n tle as p o ssib le. This means leaving limb s an d b ran ch es g rowing as high as po ssible, so th at they continue to bring sap up th e trunk. D o not strip the lim b s o n th e upp er part of th e tr ee; with n o living bran ch es to b ring th e sap up, th e tr ee trunk will qui ckly ro t and yo ur installation will fail. Rotators Be am s using the technique s described be low use a pip e m ast

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for the tree mount along with a ma st- mounted rotator. T his re q uires a mast-moun ting bracket to be att ached to the b o tt o m of th e rotator. Since the rotator is no t m ounted ins ide a tower, which would give it it s maxim um strength and ra ting , you m ust be m o re conser vative wit h th e wi nd load ing for m ast-m oun ted lo ad s by d ow n-rat ing the rotator sq uare footage cap acit y by approximately 50 %. W hile the H AJVI I V from H y-GAIN has eno ugh capacity for m ast -mounting small tribander s (15 squ are feet inside a to wer v s. 7 . 5 sq u a r e feet w hen mast mounted) , I usu all y recommend th e T2X Tailtn/ister b e c au s e its physica l strength and design bearings have more capaci ty and reliability for tree installations. You want the m o st reliable in st allation possible, beca use if yo u have a rotator problem it's no t as easy to repl ace as one m ounted o n a tower. A stress test done on a T 2X at t he factor y Photo1:Mast mounted tree installation. Note showed th at it took 1,000 horizontalbrace for torque resistance. pounds o f force on the rotator before it broke. The rotator was plate mounted by its bottom bol t mounting holes and the to p neck casting bro ke dur ing this torture test. (See Chapter 22 Rotato rs.) T here are two mast mounting brackets available fro m Hy-G AIN; one is a me dium-duty ve rsio n fo r their H A M I V; th e other is a heavy-d uty bracket fo r the ir T2X Tailmister. Since the bolt patterns are the same, you can use the heavy-du ty ve rsion o n a HAM I V installatio n as well. This wo uld be the recommen ded co n figur atio n. Get the recommended mast-mounting bracket if yo u are using other rotators also.

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Up TH E TO Jl7E R

VHF j U H F yagis VHF and UHF vertical ante nna s can be success fully tree installed. A tall tree will give yo ur antenna coverage that may astoun d you . The wo rst part of any tree insta llation is th at nothing is square or plumb on th e tree. You might have to p ut up with a little lean or tilt to your installatio n. The easiest wa y to m ount a VHF ve rtical is on a pip e, lag screwed to th e trunk at th e to p o f a tr ee wh ere it has been toppe d. Take an 1 1/ 2" ga lva nize d wa te r pip e, or a size appropriate to the rotato r tha t you're m ounting, d rill three o r four holes in it for th e lag screws, then us e yo ur 3/a" x 4" or 5" lo ng ga lva nize d or stainless lag screws to atta ch it to th e trunk . Without topping th e tree, yo u must fabricat e so me typ e of sta n do ff to ge t th e antenna a re aso na ble di sta nc e from the tree trunk; pl us yo u' ll have to clear the branches up above. T his is a les s desirabl e co nfi guratio n sin ce vertically p olarized VHF /UHF signa ls will be atte nuate d so m ewh at by th e tree. Ge t it o n top and in the clear if p o ssible.

H F beams Trees can be very usefu l for small HF trib and yagis and even two-element 40-meter beam s. Since a tree is a nonconducto r, there is no steel tower or guy wires for the ante nna to interact wit h. As a resul t, a tree-m ounted H F beam is a wo nde rfu l performer. Use the same procedure describ ed above; to p the tree and use a four to fivefoot section of 1 1/2" LD. galvanized water pipe with four \/2" x 6" galvaniz ed o r stainless stee l (SS) lag screws to attac h it to the trunk. Notice I' ve moved up from 3/ 8" to !j2" lag screws. The HF beam exerts much m or e force o n the installation th an does the VHF/ UH F insta llation, and requires stronger hardware. Be careful abo ut using hard ware sto re grade lag screws; you can easily twist the heads off co mmon or ungra ded lag screws. T he galvanized or SS versions are generally stro nger and their heads won' t twist off. An imp ro vem ent o n the pipe- mo unt m eth od is to have a hor izo nt al flange welded ont o the pipe. (See Ph o to 1.) T his will minimize the torque related forces and incre ase the reliability o f larger in stallations. Next, bring up the ro tato r with the con tro l cable att ache d and in stall it o n th e top o f the m ast. Bring up and ins tall th e mast next. Again, a th ree or four

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Photo 2:A blgyagl for tree mounting isbeing launched upthetramline.

foot piec e o f galvanized water pipe is plen ty. It's better to hav e it to o long than too sho rt bec au se you ma y want to use th e mast for a gin pole for ins talling the ant enna; you'll want a pick point high enou gh above the ro tato r to bring up th e anten na while providing eno ugh install ation clearance. Now yo u're read y for the antenna.

Tram up the antenna Tree limb s make hoisting an HF beam up to th e top of a tree all bu t impossible . T he secret to getting th e beam above the br anches is to use th e tramline and tramming technique from Chapter 23. Use a sling around th e top of th e rotator bell for your ancho r and pull ey atta chme nt point; th en rig your tramline as you wo uld normally. Do not rig th e tramline high o n the mast above th e rotator; it'll create a large-sized moment of for ce on the system and ma y damage yo ur rotator or mount.

Tag line The o the r key to getting th e beam up is to attach a tag line to one of the elements in the middle of the boom, and use it to tip the eleme nts upri ght as they approach the tree. Us e a lightweight line,

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such as 114" p olyp ropylen e, tie one end o f th e tag line to the cente r of th e boom, then route it down the eleme nt that you want to use to pivot the antenna. Twist it aro und the element two or three tim es to give it a little extra friction, then tape the tag line to th e element near the element end. T he person handl ing th e tag lin e has a job tha t requires proper timing and fin esse. Since you want the eleme nts to go almost vertical as the beam approaches the tree on the tram line, the tag line handler should be just behind the antenna itself, so when he p ulls down on the tag line, the elements go nearly ver tical to clear the bran ch es. He doesn't re lease the tag line un til th e an tenna has cleared the branches and the antenna has landed at the to p of the tree . As the tag line is released, the antenna should settle back to horizontal and, if done properly, should be right at the top of the rotator. It do esn't take much force to tip the antenna using the tag line; a minim al pressure is all that should be applied. \'(1hen the antenna has successfully lan ded at the top of the tre e, the tree person can untie the tag line from the boom. T he gro und cre w can give it a tug to pu ll it down. T he tag line should pull right through the tape that's holding it and drop right to th e ground. To

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Photo 3:An aggressive tree installation.This isa KT34XA and ispretty much atthe Iimitforthiskind ofinstallation. This antenna has been intheairfor over 15years.

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insur e th at the tag line will run th rou gh the tape, pull it back and forth a few times while it's still on th e ground to loos en the adhesive grip on th e tag line .

Hoisting the antenna into place If yo u've followed my advice by having yo ur tram line secured to the top bell o f the rotator, the n you'll need a second step to hoist the antenna in to place. Secure th e ant enna onto something convenient, suc h as ano the r sling around th e mast o r rotato r, then have the gro und crew slack off of the tram line. When it is slack, detach it and release it back to the ground; you don't need it anymore. Before dropping the tram line, alert your ground crew with a warn ing such as " I' m go ing to dro p the cable," th en " Here it comes!" o r so me o the r command. N ext, remove the pull ey and slings and re-rig th em to the to p of the mast, or at least high en ou gh to give yo u ade quate clearanc e. Reattach the haul line to the antenna bridle, th en have the gro und crew pull it up int o position. Bo lt the boom-to-mast clamp with its hardware and tighten everything. There you go ; the beam's installed. Co ngratulations.

Securing the cables T he cables may be secur ed to the trunk with eye screws , nails or just about any type o f stando ff; the n th e cables can be tie wrappe d (black o nly!) o r tap ed to th e standoff. Don't tie wrap aro und a limb ; it's conveni ent but it will kill the limb. To anchor cable s coming do wn the tr ee, I use fairly good-sized nails every 8-10 feet and then tie wrap the cables to the nail.

Preventive maintenance Co mpared to a tower-mo unted ins tallatio n, a tree is relatively high maintenan ce. Every three to five years someone should go up and do so me pruning of new growth . Little lim b s and sucker branches are am azingly stro ng and can prevent your be am from rotatin g. A nd, since this is a woode n structure, it should be inspe ct ed for ro tting as well.

28 THE TEN YEAR PLAN \Vh en you put time, en erg y and money into building a respe ctable tower and antenna system , you'd like it to be reliable and safe. T he focus of thi s chapter is exactl y that, w hat do you do to bu ild a tower and antenna system so that no major repairs should be need ed for at least ten years.

T ow ers W hile gu yed towers suc h as R OHN 25G and 45G are the m ost popular for amateur use, the se comments will be applicable to selfsuppo rting and crank-up towers as well. The only necessary co nc ept fo r towe r reliability is "DO what the manufacturer tells you to do" as far as the installation and use. Also, don't do wha t th ey don't tell you to do. In o ther wo rds, follow th e manufacturer's sp ecificatio ns exactly for guy anchors, ba se pad, materials and wind loading. According to R OH N, the most com mo n am ateur tower failure is du e to overl oad ing (a typi cal ham in stallation?) . If yo u foll o w th e manufacturer 's specs, your chances of tower failure drop to near zero. Us e the TIA or building dep artment windspeeds fo r yo ur cou nty

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to de termine th e minimum wind sp eed to which you sho uld build your system. If in doubt, ov er-e nginee r everything; if you are in a 75 MPH windspeed zone, build everything to withs tand 90 MPH winds, fo r exampl e. For the sma ll inc rem ental cost of pe rhap s th e ne xt larger size hardware, you'll gain a very comfortable margin of safety. If you have any qu estions concerning your installation or ins tallation plans, talk to som eone who has experience in station building; I guarantee yo u th at they'll have lo ts o f opinions and tips for you. In fact, talk to seve ral p eopl e. Reading this boo k is an excellent way to get started. O ne o f the mo st importa nt aspects for guyed tower reliability is proper guy wire tension. Chapter 17 is an in-depth look at Guy wires and the ir care.

Antenn as One fact of tow er and antenna ownership is that "everything has a life-sp an ." These da ys, almost all co mme rcially available amateur ante nnas are ma de out of decen t m aterials including stainless steel hard ware and high-gra de aluminum tubing, but even as yo u're reading this, your towe r, antenn as and cables are deteriorating. If you bu ild your own, don't scrimp on the materials. Use only stainless steel o r hot-dipped galvanized hardware. Cad mium plating and o the r hardware finish es will not last the ten years that we're shoo ting fo r. Avoid th em . Fo r wind surv ivability and heavy duty construction technique s, I reco m me nd Dr. D ave Leeson's, W6NL, ex-W6QH S, book Prysical Design if Yagi Antennas. H e covers constr uctio n techniques and ma terials exhaustively and includes all o f the technical data to back up his con clusions. T here is much valuable information througho ut the bo o k. Subjec ts inclu de rotato rs, masts, fasten ers and literally dozens of other to pics. You sho uld also use antioxida nts on every electrical and an tenna connection .

Baluns Baluns (balanced-to -unbalanced) - are matching devic es used at antenna feedpoints to 1) balance th e symmetry o f antenna currents and 2) preven t, or cho ke, the o uts ide o f th e coa x shield from radiating and they are a poten tial pro blem . The Hy -G AIN BN -86 tha t was

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supplied for years for the TH6DX jTH7DX and others was wellkn own for its "fuse" capabilities. Put a little to o much power thro ugh it and it opened like a fuse. Whole books have been writte n on baluns and I recommend you get one to learn more about the se devices . Most baluns are out in the weather for years and do their job with no maintenance. Unfo rtunately th ey som etim es fail an d the re's no way to test one easily. N ot only do you ne ed special test equipment to pe rform a test, but also you have to get the balun off th e antenna and into the shac k - many tim es a difficult process. T he only way to easily test a balun is to substitute another one and see what happens. A circularly wound coax ch oke can some tim es be a m ore reliable ch oke but they need to be constructed for a certain frequency sp ectrum and they have specific construction pa rameters. There's no magic bullet fo r balun reliability but m any o f th e available commercial products work well. And you can always roll your own.

Connectors Silver-plated connectors installed with silver sold er are better in the long run. Problems th at arise are gen erally due to poor weatherpro ofing , so be cert ain to follow all of the techniques in the Weatherproofing ch apter. N ever us e solderless or crimp-on connectors. Always use plier s to tighten connectors; finger-tight just isn't good enough .

Coax N ew co ax, with a non-contaminating jacket, is th e minim um for reliability.

Weatherproofing Since inadequate weatherproofing is one of th e biggest problem s in station performanc e, follow the instruction s in th e weathe rpro o fing chapter and thi s wo n't be a problem .

Rotators Its my opinion you' ll be luck y to have any rotator sho rt o f a

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prop pitch last reliably for ten years. Sorry. Fo r start ers, th ough, put in a bigger rotator th an you ne ed. T he less stress you pu t on it will result in longer life span. The o the r th ing th at you can do is anticipate rotator failures and m ake the ir replacem ent an easy one-perso n job.

Grounding system Because it's mo stly o ut o f sight when p roperly ins talled, a gro unding system wo n 't impres s yo ur ham friends as will yo ur towers(s) and beam (s). Follow the techni gu es detailed in Chapter 24. Use antioxida nts wherever th ere is an exposed electrical connection.

Hardware Use o nly stainl ess steel (SS) or galvanized hardwa re suitable for outdoor use.

Wire antennas For maximum wire antenna int egr ity, use a center ins ulato r that will not o nly acco mmoda te a PL-259 as the feedlin e co nnec tion, but will also take the strain o ff o f the co nnec to r as it hangs in the air. Use a black tie wrap to secure th e feedlin e to the in sulator. Strand ed antenna wire o r solid is your choice; both have th eir pros and co ns. Be sure to use silver solder on all o utdo o r co nn ectio ns. Use UV resistant black dacro n ro pe for the haul ropes.

Crank-up maintenance Use a cable lubrican t at least once a year, preferably twice. Inspe ct cables for o bvious dam age, bro ken strands, o r rust. Mor e information in Chapter 30.

Annual inspection Perform a tower and ant en na system insp ectio n once a year, pr eferably whe n th e weather is nice.

29 REFURBISHING A TOWER Ma ny towers have had o ne o r m ore previou s lives. A used tower can ofte n be an eco nomical way to go, and ge nerally will save significa ntly ove r buyi ng all new steel and hard ware.

P re-purchase inspection Take a long, hard look at what you want to bu y be fore you fork over your hard ear ned money. Often the owner doesn't know or has forgotten the specifics relat ing to his tower, including manufact urer, type , etc. The main thing you're interested in is its condition. You want to see if there is any significant damage or corrosion. If any tower, including a crank- up, is in good shape, it will loo k like it. It will be clean and there will be little or no corrosion. Minor dents or bends th at don't affect the structural integrity are usually okay. Many times these can be straightened, repai red or ignored. In th e ca se of corro sio n , prim ar ily rust , determine whethe r it is sur face bl eed ca used by something else rusting o nto the tower o r whether the rus t has p en etrated the ga lvanizing. Hot dipped towers suc h as R OH N 25G and 45G have excellent ru st res istance;

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their g alvaniz ing sho uld last twe nty yea rs or more. T owers stamped from ga lvanize d m etal, such as ROHN EX, hav e thi n ner zinc co atings and thu s ha ve sho rter se rv ice live s. E xamine guy wi re hardwar e with the same critica l eye . D on't buy o r reu se any badl y corrod ed guy wire or ha rdwa re . Crank-up tow ers can be yet another can o f wo rms. The wea k links for crank -ups are the cab les. Be very cautio us if there is an y co rrosion, deformities or kink s in the cab les or significant ru st. Recabling a crank-up can be a difficult job; contact the manufacturer for instructions and replaceme nt cab le. See th at th e pull eys are in good shape ; th ey should turn witho ut binding. The ru le here is caveat empto r-let th e buyer beware! Don't forget to weigh th e co st of refurbishing into th e equation. It is one thing if yo u've go t lo ts of time and not much money, but if yo u spe nd a month wire brushing and co ld galvanizing a tower, you co uld be spe nding as mu ch as the co st o f a new tower. If you're talking to someo ne and they have a fifty-fo ot self-s upporting tow er but th ey don't kn ow the br and, nine tim es out o f ten it will be ROHN ax, not wo rth the effo rt o f taking down . These are usuall y badly ru sted and onl y fit for a trip to the dump.

Getting it ready O nce you ge t you r tower home, pu t each section across a pair of sawho rses and go ove r it with your wire brush and co ld galvanizing paint. Fo r really ru sted portions, use a wire brush attachme nt on a dr ill motor. Wear a respirator or mask to prevent inhaling the zinc and other materials. \'V'hile it's o n the sawhorses you can do a visual chec k for straightne ss by looking down eac h leg for anything unusual or be nt. N uts and bolt s are often either missing or un usabl e. G et replacem en ts only fro m th e tower manufacturer's specs. Off th e shel f nuts and bolts fro m yo ur hardware sto re are probabl y not suitable; fact ory hardware has a certain grade rating that th e parts mu st me et, while hard ware sto re parts are likely go ing to be a lesser grade . Professional standa rds ge ne rally do not allow reuse of structural nuts an d bolts o n co m mercial towers. As far as cold galvan izing goes, th e most convenient mean s of applicatio n is fro m a paint spray can . This is a case where you ge t what yo u pay for. The cheaper o nes will run and so metimes don't

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adhere very well. LPS makes a very good one but it's on the more expe nsive end o f the spe ctrum . Welding suppl y stores carry go od pro fession al varieties. Order a new base sectio n or fixture fro m the factory or fabr icate one. With R OHN 25G and 45G, yo u can simply sink th e bottom of th e first sectio n in to th e concrete as yo u pour the base foundation. Follow th e manufacturer's specifications, and the information in thi s book, and yo u'll be able to install a safe reliabl e syste m.

30 MAINTENANCE AND ANNUAL INSPECTION Now that you've spent all that time and money on in stalling your dr eam ant enna and tower system , you'll need to do peri odic preventi ve maintenance (Plvl) and inspectio n to catch anything before it turns into a problem.

General maintenance If yo u've foll o wed th e directives and steps de scribed in this book you 've alre ady taken the m o st im po rtant steps in in suring the sa fe ty and reliability of yo ur tower and antenna sys tem. Fo llowing the manufacturer's sp ecificatio ns, using th e right hardware, using antiox idants and over-engin ee ring everything are the ke ys to suc cess. A t this point, yo u' ll p robabl y not require much in th e way o f ge ne ral main tenance. The two m o st likel y things tha t yo u' ll need for gen eral m aintenance ar e a wire brush and co ld galvanizing spray p aint, as rust is pro bably the only thing about which yo u 'll have to worry.

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Annual in spection An an nual inspection is a critical pa rt of yo ur PM program. Most commercial co mpanies do it religious ly; many insur ance co mpanies req uire it as a condition of insur ance coverage. An annual inspection entails examining everything in the tower and antenna system, incl uding the ground system, concrete anc hors an d foo tings and tower structure. In addition to ann ual inspections, all installation should be inspected after ice storms or wind storms that exceed 60 mph. You should get in the habit of do ing a quick visua l check ever y time that you clim b the tower. A log book of inspections, exceptions and repairs is a handy reference item. The information that follows is based on commercial and ELA/ TLA-222 tower inspections standards: Tower structure 1. Check for damaged or faulty mem bers. T hese are the tower legs and braces. With welded towers such as ROHN 25G and 45G, the me mbers cannot be replaced witho ut replacing the who le section; minor bend s or damage that do not alter the structural int egrity can usually be tolerated. 2. Check all welds for integrity. 3. E xamine the condition of the finish and an y corrosion. Loo k for rust patches; use your wire brush and cold galvanizing paint to repair it. 4. In addition to visually che cking any bo lted co nnections, you sho uld put a wre nch to at least 10% of the m to check for tightness. Any loose nuts or bolts sho uld be retig htened. Also look for missing hardware an d rep lace it immediately. Tower alignment 1. T he towe r sho uld be checke d for plumb. A guyed tower is allowed a maximu m deviation of o ne part in 400 , or three inches pe r 100 feet. Wh ile a transit is the best way to chec k tower alignment, an electroni c level willgive you 0.10 accuracy, o r a bubble level will indi cate relative plumb . Even simp ler is a long piece o f string with a weight on the end, hel d at arms- length away fro m th e tower; just sight th e string alo ng th e tower leg for a very quick and fairly accurate indic ation of tower plu mb . For self-s up porting towers, th e allowed declination allowed is 1 part in 250 o r 4.8" in 100'. 2. Check the guy wires and guy insulator s, using binoculars for the ones that aren't close to th e gro und o r the tower. 3. Examine all guy wire and guy wire hard ware including Pr eformed grips , turnb uckles, clamps, and clevises for damage. Make sure th at all turn-

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buckle safeties are intact. 4. Check guy wire tension with an instrument or another technique. 5. Exa mine the tow er base and guy anchors . Look for any cracking of the concrete. Also look for evidence of movement in the soil o f the ancho r rod s or base. Check for rust and/or corrosion. Excavate a buried ancho r rod for twelve inches to inspect for hidden corrosio n. Antennas, cables and appurtenances 1. In spect antenna, bo om-to-mast bracket and boom tru ss hard ware for loose or missing hardware. Test nut s for tightness. 2. Look at each feedpoint joint and coax cable join t for compromised weatherproofing. 3. Check all cables for abrasion, binding and attachme nt. 4. Examine all appurtenances (anything that's attached to the tower) for missing hardware or corrosion.

Grounding system 1. D o a visual inspection of the gro unding system. Redo any connections that are corroded.

Yo u sho uld co rrect any problems that yo u di scover in yo ur inspection . If yo u're not sure about th e se rio us ness o f so meth ing yo u've fo u nd, talk to a kn o wled geable buddy o r co ntact the manufacturer for advice. W he n yo u d o a tower in sp ec tion, yo u sho uld ha ve eno ug h sup plies to redo sev eral coax connect or joints if nece ssa ry, as we ll as a note pa d and pencil to wri te d own any di screp ancies that may require further actio n. You'll be able to take care of most problems o n the spot as we ll as to know what else yo u m ight need to fini sh the repair s. I always p us h and pull o n antennas and ap p urtena nces to see if an ythi ng is lo os e. So m ething mi ght lo o k o kay b u t pushing o n it might reveal lo o se hard war e o r so me other problem.

Crank-up m aintenance C ra n k-up to wers are complex mechanical co n trivan ces. W hile so me are h and cr ank ed , m an y have a m o tor, gearbox, cables, pulleys, and lim it switches - all of whic h should be ca re fully ins pected twi ce a year. T he electric m oto rs and ge ar box ar e ge nerally bulletproof and the only in spections are to ch eck th e oil level in the gearb ox , th e conditi on o f th e d rive b el t o r ch ain (some so rt o f conditioner is

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helpful for each), and th e operatio n of the cable drum (the re are probably so me Ze rk grease fittings th at need atte ntion). Pulle ys are so metimes custom made by th e man ufacturer so you may not be able to run down to the local bearing sto re and bu y o ne. Some sheaves are made by the manu facturer and then an offthe-shelf bearing is inserted in the middle. T his one you probably can replace. P ulleys need to turn and no t bind so a good thing to do is to watc h the pulleys if they're exposed enough wh ile the tower is being raised o r lowered and see if there are any problems .

Crank-up cables Crank -up cables sho uld be lub ricated at least annually; twice a year wo uld be even bett er. Use a cable lubricant such as PreLube 6 and be sure to check fo r dam age while you're hanging aro und the towe r do ing th e lub e job. See Chap ter 34 for m ore information.

31 WHEN SOMETHING FAILS Failures to your in stallatio n can co me in man y forms but wind is generally the co mmo n denominator. Rust, me tal fatigue and ove rloading aren't usu ally a p ro blem un til th e wind starts to b low. Other ca uses o f failure co u ld b e lightning strikes, ice, vandalism or accidents.

Assess the damage T he first thing to do is a visual in sp ection. Using bin oculars if possible, take a look at everything fro m the gro und to see if anyt hing is bent or broken . If some thing is swing-

Photo 1:Abent mast. Someone should've read theMastchapter inthis book.

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ing in the wind, that's a maj or problem. If there is obvious damage, try to determine if it is in danger of falling. If so, evacuate th e endangered area immediately and alert local emergency services. T his is esp ecially tru e if it looks as though it could fall on power lines, sidewalks or roadways. If you have damage th at isn't an imminent danger to life or property, keep an eye on it until the storm is over to ensure that it doesn't get wo rse. If you have the opp ort unity, take som e snaps hots or video tape of th e damage for documentation.

Prevent further damage Your ne xt task is to take prudent step s to prevent further damage, both to your property and to the property of others. T his is not only common sen se but also a requirement of the insurance company. You want to avoid or minimize the possibility of liability lawsuits for personal injury or the property damage of others. T ie anything off th at you can but do not attempt to climb th e tower!

Photo 2:Oops! Apotentially dangerous removal. Acrane was used forsafety.

File an insurance claim After the storm is over, call your homeowner's or renter's insurance agent and notify them of the loss. Do it orally first, then follow-up with a letter. The insurance company may require a 'Proof of Loss. "T hey'll give you a claim number that you'll need to use in all written and verbal communications. Start a file with all your documentation, plus the other

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Photo3:The bighurt. Ice damage atW7EJ.

paperwork that you'll start accumulating. Keep notes of every conversation with your insurance agent or claims adjuster with dates and times; you may have to refer to them in the future. At this point, you may want to write down all pertinent facts surro undi ng the loss for reference also. Send copies of your photos with your loss letter.

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Estimate of repairs You'll m ake things very easy for your claim s adjus ter if you include an estimate o f rep air along with your let ter and ph o tos. T he ad juster has probab ly n ever ru n in to a tower loss before and wo uld

Photo 4:Winddamage.This isnotgoing to beremovedbyone person on thetower because it iswayoutofbalance.

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ap preciate your help in getting a quote. Contact yo ur local commercial rigger or antenna installatio n company and they 'll give you the quote . Ins urance companies will want professional workers to perform professional repairs to your loss; the y expect to pay the going rate and they expect licen sed contractors to do the work. Be sure that your estimate for tower repair covers all of the work includi ng: disma n tling damaged parts, hauling away damaged part s and disposal, clean- up, labor for reinstallation including assembly o f antennas, labo r for reinstallation of tower, rep lacing all damaged materials including hardware, cab les, rotators, etc . Don't be surprised if the estimate comes in q uite a bit higher th an yo u expect. Not only are you paying pro fessionals to do all of the wo rk, but a dam aged tower o r an tenna system can be ha zardo us and a cran e or other piece of equipment may we ll be needed to remove it safely.

Stay in your comfort zone N eedless to say,don't consider getting invo lved in the removal and repair of the damage unless you feel comfortable with it. If there is any doubt at all in your mind, either get the p rofessionals in or bring in a piece of equipment such as a crane or boomtruck. One of the primary I directives in this type of wo rk is that "it ha s to be rigged for removal the same way that it was installed ." That is, if it wen t in with a crane, then yo u need a cran e to remove it. If yo ur ma st was installed by bringing it up through the middle of the Photo 5: This is how the damaged to wer, you probably wo n't be ab le antenna was removed . It's still a to remove by lifting it out with a handful. ginpole, especially if it's bent. What yo u don't do is send your nephew shinnying up the bent ma st. If an ything is at a precarious or dangerous ang le, don't touch it- send for th e professionals!

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32 INSURANCE This chapter tuas iuritten ry Ray Fallen, N D 8L , who has been an agentfor The State Farm Insurance Companies since 1988.

Property insurance There are several cav eats regarding homeown er's in sur an ce co verage as it ap plies to to wers and anten nas . Firs t, mo st U.S. hom eowner's policies are bas ed up o n standard language pro vided by the Insur ance Ser vices Office (ISO) . E ach co mpany mo difies that language on a state-by-state basis; so coverage th at ap plies to towers in Ohio, may no t apply to tow ers in Florida . Coverage may va ry from compa n y to compa ny and on differen t policy types with th e same company. Because o f all the state-to-state differences, I can't tell you exactly how your tower will be covered, bu t can give you so me ge ne ral guidelines. W hich brings us to caveat number two...wha t's covered in your homeowner 's policy is described in the policy itself. What's NOT covered is in the policy. Your du ties following a loss are described in

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the policy. How the loss will be paid is, you guess ed it, described in the policy. If you're picking up a pattern here, go to the head of the class. You NEED to spend time with your agent, be fore pu tting up your tower. If you've already pu t up your tower...what are you reading this for? Go see your insurance agent...RIGHT NOW! Damage to towers, rotors and relate d antennas is covered by Dwelling Extensio ns, Other Structures or Ap purtenant Structures coverage. The name of the coverage depends on the Insurer. Fo r example, State Farm's O hio Homeowner's Policy describes Dwelling Ex tension s as "other str uctures on the residence premises, separated from the dwelli ng by a clear space." Other structures are permanently attached to or otherwise form a part of the realty. Typically,ot her structures are covered for 10% (Ten Percent) of the dwelling amount, which, for mo st of us, would more tha n an adequate amount. If you're K3LR or W3LPL, that ma y be another story. Remember, part of the rep lacement co st of a damaged tower is professional help in removal and repair, in addition to the new, replacement cost of the damaged items. In addition, fences, pole barns, gazebos, satellite dishes , detached garages and in-ground swimming pools are also considered in Dwelling E xtensions, not just your tower. So add it all up and if yo u need more coverage, buy it is BE FORE you have a loss. Ins ur ance companies are reluctant to sell yo u more coverage right after you've had a loss. In most homeowner's policies (unless you pa y for more) if the damage exceeds 10% of the dwelling coverage, yo u pa y it. So do your homework. See your agent. Ask a lot of que stions. Antennas sup po rted by trees and ground mounted verticals are not permanently attached to the real property (som etim es much less permanently than we'd like) and, as such, are considered pe rsonal property. The good ne ws is personal property is covered for 70 to 100 % o f th e dwelling cost...the bad ne ws is generally the coverage is less broad than dwelling extensions , but wind and lightning damage is usually covered. The distinction between dwe lling (including dwelling exten sions) and personal property coverage is: if it's nailed down, it' s considered dwelling coverage...if it's not it's personal property. A Cushcraft R7 on a piece of pipe in a sack of sand mix is personal property. E ighty-feet of Universal Self Supporting Aluminum Tower in a twel ve cubic yard block of six sack, rebarred concrete is a dwell-

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ing extension. No claim s adjuste r worth his salt will ever co nfuse th e two. The bottom line is this: don't eve r rely o n your ham radio buddies, yo ur neighb o r or your bro ther-in-law for advice o n ins urance. Call your insurance agent, bring him up to date on your ins tallatio n and ask hard que stions. Specifically, if my tower installation is dam aged, how will it be cove red? If he doesn't know, m ake sure he finds out and shows you, in writing (in the policy contract) how it will be covered or why it wo n't be. If towers/ ant ennas are speci fically excluded in th e policy, what will it co st to pu rcha se the coverage you need? Take pictures of your tower and give your agent an accurately priced inve ntory of your installation. Be p repared to pay the appropriate premium and sleep so undly when the north winds blow. If, on the other hand , your agent can't o r wo n't provide you with the information you need, th en go shopping for a new co mpany or a new agent with the same compan y. Rem ember, every time you pay yo ur prem ium, your agent gets paid...he OWES you th at service, Those hams renting their home still have a need for coverage. Some rente r's policies (tena nt 's form s o r H O-4s) provide cove rage for personal property ONLY So me HO-4 policies provid e 10% of the co ntents coverage amount for bu ilding improvements, similar to the dwelling extensions coverage in a homeowner's po licy. Again, fo rewarned is forearmed ...talk to your age nt. I f you don't have renter's insuranc e...get som e, especially if you have a tower up, if for no other reaso n than ge tting liability insurance (see the next sectio n). The landlord's rental dwe lling po licy insurer won't pay for a tower installatio n that doesn't belong to the landlord, for the same reaso n your contents aren 't covered by th at po licy. Maybe better to pu t up a G5RV and save the tower for your first house.

Liabili ty in surance A fundamenta l principle of insur ance is tha t you bu y coverage for the things you can't afford to lose . Most folks driving 1985 Yugos do n't b uy co llisio n coverage...most folks driving a n ew Mercedes do. T hat be au tiful new tower you're putting up is wha t the personal injury plaintiffs bar calls an "attractive nuisance ." If o ne of the neighborhood kids decides to scale Mount Rohn and takes a

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tumble from for ty feet up, you're going to ge t sued. You can argue about tresp assing until you're blu e in th e face...but you're going to ge t sued and you're go ing to get sued for a lot of m oney. You do have so me p rotection in yo ur hom eowner' s p olicy. Typ ically, mo st homeowner's liability coverage is o nly $100,000 to $300,000. I say only, bec au se if som e reas onably competent attorney parad es a teenager in a wheel chair in front of a jury...$300,000 is only a down pa yment and yo u'll be on the hook for th e rest, to the extent yo u're co llectible. Yo u're collectible if you have a job, equi ty in yo ur home o r bu siness, a ch ecking or saving s account, inv estm ents, a pen sion plan or an y other asse ts. If yo u can afford to los e those thi ngs fine ...otherwis e, I would strongly encourage you to purchase at least a one million dollar pe rsonal liability umbrella policy. It doe sn' t co st a lot, typically less than a dollar a day, and will give you great peace of mind. After all, if yo u're sued for a million bucks and you los e, do you want to write the check or do you want your insurance company to write the check? N ow, go back and read this paragraph again...it's very important.

Prevent further damage Homeowner's in surance policies include a section on your du ties after a lo ss. Specifically, yo u are required to protect th e your property and the property of others from further damage o r loss, make rea sonable and nece ssary temporary repairs required to protect the property and keep an accurate record of repair expenditures. You ob viou sly want to avoid personal injury or proper ty damage lawsuits from your neighbors, but yo ur insurance carri er do esn't exp ect you to put yo ur life in danger. T ie off anything yo u can, bu t do no t climb th e tower! Keep tr ack o f tim e that you spe n t on th e project (clean up, tie- off, etc). Your adjuster may co mpensate you for your time by offsetting it against your de d uctible. Typical rates for an ins ured's lab or are from $6 to $10 per hou r. D on't expec t to be paid for tim e on the pho ne get ting quotes or winds hield tim e go ing to the local radio em porium , th ou gh ...we 're talkin g sweat wo rk.

File an insurance claim Call your insurance agen t and notify th em of th e loss as soon as possible. Do it by phone and yo u ma y want to follow up wit h a

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short letter, fax or e-mai l. Start a file documenting the claim th at shou ld include: 1) notes on conversations with your insurance agent and claim s representative; 2) estimates o f items to be rep aired and rep laced; 3) any tim e YOU spe nd actually wo rking on th e dam age; 4) ph otographs and inventory o f damaged or destroyed pro perty 5) related claim data, such as claim number, adjuster's name/address/ ph one/ fax/ e-mail address. G et on the phone and get current street prices and availability from several vendors . If th e items damaged o r destroyed are no longer available , you may be entitled to replace the m with item s o f "like kind and qu ality." Be prepared to document th ese differences and discu ss th em with your claims rep. Also, as my sainted grand ma used to say, "Pigs get fat...hogs ge t slaughtered. " If you can bu y a new rotor/antenna /tower/whatever at a great price, turn that price in...not the list price. Most claims adjusters get real cranky (and rightfully so) if the y feel a claim is being "padded." At be st, it slows down th e process. At wor st, you may find yourse lf facing felony in sura nce fraud charge s. A wo rd to th e wise sho uld be sufficient. One other item, in the overa ll scheme of things, yo ur damaged tower (unless it's going to fall on the neigh bor's house) is probably not as high o n the claim s representative's priority list as so meone 's home with major structural dam age. In time s of major catas trophes: hurricanes, hailstorms, tornados and the like...the re's never eno ugh tim e and people to get things done...be patient and be reasonable. Before any work is done, insist that yo ur contractor provide you with a current certificate o f contractor's liabilit y insurance (his malpr actice coverage), a curren t certific ate o f wo rke r's compen satio n coverage and local references. If the p erson is a pro fessional, that wo n't be a problem . If he's a fly-b y-night er, ins ura nce pro bably will be a probl em ...and you just don't want those headaches. If the co ntractor tells you th at his associates are "subco ntracto rs," tell him you wa nt to see the "subcontractor s" certificates o f liab ility an d worker's compen satio n insurance. D on' t even co nsider ben ding on this. Most ins urance co mpanies will writ e a check for the total damages (less yo ur deducti ble) when th e wo rk is completed. If you want a che ck prior to the start of wo rk, th e adjuster ma y reduce th e pay-

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ment for any depreciation o n th e dam aged property (called an actua l cash value or ACV set tlement) and then pay th e balance when the wo rk is co mpleted. This is co nsiste nt with the langu age in mo st policies and keep s everybody honest. Most ho meown er's policies settle lo sses on a repl acement cost basis..., which mean s new stu ff for old...when the ne w stuff is purchased . Make sure you kno w whe ther your policy pa ys replacem ent cost or actual cas h value BE FORE yo u suffer a loss. If you have an ACV policy...get it updated...righ t now!

Ray Fallen has been an agent for The State FarlJl lnsurance Companies since 1988. The opinions expressed are those 0/ the author alone, and are not those 0/ The State Far»:Insurance Companies. The coverages described1JIq} not be available or II/ CD' not appIJ' inyour state, province or country. YOI/ arestrong/y enconraged to reuien:your bomeoiuner's policy and tower installation withYOl/r insurance agent to determine appropriate coverages and amounts. Thepronouns "be] his" are usedin a non-sexual, gender-neutral basis. Ray's callis N D8L. H e's been a ham since 1964 and is a member 0/the North Coast Contesters CII/b, K3LR 's Multi -Multi team, DX CC, A RRL and the Doub/e-O Repeater Group (N8GO). H e mq} bereachedvia e-mail at: [email protected] or via the State Farn: IV eb Page (JVlvlJJ.statejartl/.colJI.)

33 ANTENNAS Alt hough the focus of this book is tower s, antennas are th e point of the tower structure. At th e top of th e pile (and the pileups) in terms of "death ray" effectiven ess are stacks of big antennas. Mo st high ly co mpetitive stations use monoband stacks on each band (six elements over six elements etc.) for 10-, 15-,20- and even 40-meters. At the bottom of th e totem pole in terms of effectivene ss are trapp ed , quarter-wave multiband verticals tha t require a good gro und radial syste m and typically lack them. All o ther antenna systems fall in between the se two extremes. Full sized wire ant ennas will work better than trapped wire antennas, while a small beam will work circl es aro und just about an y wir e setup. If you alread y have a small trib ander, to increase your signal appreciably yo u'll have to at least double the boom length. In general, gain is a direct functio n o f boom length. J ust decide what's practic al and affo rdab le for yo u and go to wor k pu tting it all together. (Fo r mo re information on ante nna performanc e, the author and H . Ward Silver, NOAX , have published landm ark ant enna re-

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po rts that actually co mp are o n-the-air performanc e using a dipole as a reference. For co pies o f HF T'ribander Performance - Test Methods And Results and HF Vertical Performance - Test M ethods And Results, co ntact www.cha m pio nr adio.co m .

Temperature cycle An im portant tip relating to antenna construc tion is, afte r assembling the antenna, let it sit overn ight, then retigh ten all o f the nuts and bolts the next day. T he hardware will have te mpe rature cycled from warm to cold and warm again and some of the hard ware will have loosened up during th at tem pe ratur e induced expa nsion and co ntraction .

Antioxidants Co rrosio n is a big problem for antenna and tower systems. By using galvanized or stainless steel hardware yo u' ll stay away from most corro sion problems. U n fortunately (or fortunately) most ante nnas are made o f alumin um and are subject to alumi num oxida tio n in the element joints or or other electrical co nnections. W henever you build an an ten na, use an antioxida nt suc h as the ones discussed in th e co rro sion chap ter. Altho ugh so me anten na manufacturers pro vide thi s pa ste with their p roducts (FORCE 12 and MOSLEY to mentio n two), som e man ufacturers do not provid e an y, alth ou gh th ey ma y reco mmend its use.

Feedline jumpers With man y beam antennas, the feed point is o ut of reach from th e tower. I prefer to use a jumper, o r pigtai l, just long en ough to reach from the feedpoint to th e ma st o n the tower. That way, all you have to do is plug the m ain feedline into th e jumper with a barrel connector, weatherproof it an d everything 's read y to go . T he amo unt o f lo ss in troduced by an ad ditio na l PL-259 or two and a ba rre l connecto r is negligible on H F; it's not wo rth wo rrying abo ut. You'll understand how co nve nient thi s is if you ever ha ve to drop the an tenna in th e future .Just disconnect the jum per and lower th e antenna. If you've connected the antenna to o ne lo ng piece o f coax, you' ll have to work yo ur way o ut to th e feedpoint and disconnect it th ere before yo u can lower it. Use a jumper, it' ll save yo u a lot of hassle.

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Keeping the elements from coming apart Most HF be am s have tapered elem ents mad e up of decr easing sizes o f alum inum tubing th at are ge nera lly held toge ther by co mpression with a hose-clamp or rivet. Here's a tip that will not only add to the mech anical int egri ty of the antenna but will also enha nce the electrical reliab ility. After you've asse mbled the an tenna wit h hoseclamps, tested it and are ready to install it, put a self-tapping screw or rivet through each elem ent whe re th e tubing overlap s. The best kind o f self-tapping screws are called TEK scretus; th ese have a chisel point which will start the screw in just about any material and are available in m ost hard ware sto res. Sheet metal screws tend to break off when being installed which is not a probl em with th e TEK screws. They are available in Phi llips head as well as nut sizes for yo ur nu tdri ver or co rdless drill. They'll hold th e eleme nts together as well as provide a fine additio nal electrical connec tio n between the different sizes of tubing. O f course you can use rivets as well as po pu larized by Force 12. If you're concern ed abo ut the boom twisting, you can pu t a few through the boom as well. These sma ll holes can be stress risers and in so me instances may cause failure. If you 've got winds strong eno ugh to overstress th ese small holes, chances are th at the antenna will blow apa rt befo re the ho les are ove rstressed. In P/! pical Desigll of Yagi .Autennas, Dave Leeson, \\!6NL, ex-\\!6QHS, recommends drilling any holes (such as for self-tapping screws) on the un derneath side o f an element. Speaking of Fo rce 12 antennas and rivets, in my op inion th ey are a great improvement to antenna mec han ical desig n. By replacing the traditional hoseclamps, they have reduced the cost and the weight o f the antenna while eliminating a device that always seems to get hung up o n something while yo u're trying to install or remove an antenna; that is the ho seclamp that tends to snag on guy wires, antennas, and just about anything else in the vicinity. The only complaint agains t rivets that I'm awar e o f is th at in perpetu ally windy regions, the single row of element rivets will allow th e inner piece to move eno ugh that eventually the joint will fail and the element will come apart. In this case, or if you just want to insure more reliability, just put another row of rivets o n the oppo site side of the existing row. Or, in extreme cases, add two rows 120 degrees apa rt fo r a total of th ree and your failure rate will d rop to just about zero.

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Baluns Balun s for beam antennas have a checkered hist or y. A balun (from "b alance d-to-unbalanc ed ") is used to match a balanced load (like a dip ole or driven elem ent) to an unbalanced load (typically coax). The o ther purpose is to keep the ou tside o f the coax shield from radiating and causing RFI. Fro m power handling limitations (the fuse syndro me) to poor mechanical and electrical design, balun s can be seen as a necessary evil. Modern balun s are designed to be "cur rent-type" baluns as opposed to the previous "voltage-type" balun des ign. T here are several goo d books available abou t balun s and feed lines; refer to thes e for mor e definitive informatio n. Another balun design is to use a coax ial RF cho ke. It's simply a coil made up of eight to ten turns o f RG-8 or whatever coax you're using with a diam eter o f six to eight inches. It's really reliable as th ere are no inductors to sho rt and no toroids to saturate o r bu rn out. T he mai n d rawback to a wound RF choke is that they can be pretty imp recise as far as being useful o n th e freq uenci es o f inte rest. This is where having so me test equipment to actually look at th e choke and its param eters wo uld be ve ry useful. O therwise it's a hi t o r miss pr opositi on. Some ante nna manufacturers provide baluns with their products, o thers recommend a coiled RF choke. Yo u should follow the manufacturer's reco mme ndations.

Split coax Most manu factu rers use some type of feed point system that will enable you to sim ply plug your PL-259 directly into th e feedpo int or balun . T his is accep table if you do n't forget to do your weathe rproofing. But a few co mpanies want you to split th e coax and feed the ends of the cable directly to atta chme nt points o n the driven element. That is, cen ter co ndu ctor o n one side and shield on the other. It works fine but th e junc tion of the coax (the bottom of the Y) is very difficul t to seal. Water will simply wick down th e o uter shield and into your shack un less yo u take great pains to weatherproof it. There is an optional method which works o n antennas such as those fro m C USHCRArT. Just connect a dip ole connector to the driven elem ent, the n plug a PL-259 int o it. A dip ole center co nn ector has a

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female PL-259 (an 50-239) embedded in a plastic material with two leads coming out to connect to the sides of the dipole. The exception to the split coax feed is the M OSLEY line of PRO antennas. These use a split feed, and it is very critical to successful installation of the antenna. Once again, do what the manufacturer specifies.

34 TOWER REMOVAL What goes up m ust come down ; th at goes for towers an d ante nnas as well.

Danger, Will Robinson! I can 't emphasize this enough: The MOST D AN G ERO US activity around towers is removing a tower tha t you know nothing abo ut. You CAN'T be too careful in this situation. CARE FULLY inspect everything you can from the ground. Pu sh and pull on stuff to see how secure it is. In the case of badly rusted guy wires, you may want to use temporary guys to make if safer. This is a case of "If you feel that it's dangerous - it pro bably is." If you 're not sure about the int egrity of the tower struc ture and you feel un comfortable abo ut even climbing it - WALK AWAY I'v e done this several time s and never regretted it.

The removal prime-directive T he mos t impor tant thing to rem ember in disassembling a towe r

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and antenna system is th at "it mu st be rem oved the same way in which it was installed." In o th er words , if it was installed with a crane, it almost certainly has to be removed by a crane. If a m ast wa s brou ght up th rough th e middle of the tower, it'll probably have to be lowered th e same way. Fo r an undamaged antenna and tower system, just reverse the steps o utline d in th e installatio n chapter; disconnect the feedlines , rig up a tramline and lower away. Two of the m o st useful to ol s in thi s phase o f wo rk are a hack saw o r h and g rin der and a can o f L iquid Wrench. Fast eners are typically thoroughly rusted and gen erally difficult to impossible to rem o ve. R OH N 25G o r 45G sections can be difficult to take apart for a couple of reasons. If the builder didn't put an y grease in the legs, th ey may be oxidized together. If the build er overtightened the leg bolts and ovalized the legs, the legs will be compressed together. In either case you'll need som ething to pry the sectio ns apart. The traditional method was to use a sm all aut omotive hydraulic bottle-jack and a couple of two-by-fours. This technique work s fine, but yo u must pu t a leash o n everything so that nothing gets away from yo u and falls. A TonerJack allow s yo u to pry th e sectio ns apart with relative ease. The only caution is th at you may wind up bending the tower br aces o r popping a weld by exe rting too mu ch force with the TowerJack . If that is the case, the legs may be extremely jammed and you may have to reso rt to th e bottle jack anyway. O f course th e easies t and safest way to remove a tower is to ge t a crane in to lift ever ything. For the co st of a crane ver su s the ch ance o f an accident, it' s really a no -b rainer. I' ve u sed a cr an e to lower 100 ' o f 25G and als o 90 ' of 45G wi th no p rob lems or dam age. If yo u're rem oving a tower that you can't clim b, there are a couple of options. If yo u've go t the room to let it fall, carefully cut o ne set o f guy wires and then pull one o f the o ther o ne s to encourage it to start its downward journey. You might have to cut additional guys. A freestanding tower can be felled like a tree. Ju st be RE AL CA REFUL in all cases. If you don't have the ro om to drop it, you can use a crane to pick it up and lay it on the gro und. The trick is getting up on th e

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tower to attach the slings and th e crane hook. T he best thing to do is to get a crane with two hooks. You'll use o ne to run you up in the man-basket whe re yo u'll the n atta ch the seco nd hoo k to th e slings. H ave the ope rator put a little ten sion o n th e tower to hold it securely and th en have him lower you in the man-ba sket. O nce you're o n the gro und and the crane has the tower, cut everything ho lding it and then lift the tower up and lay it o n the gro und. Using a tagline will he lp yo u maneuver th e towe r as it's being lowered.

35 WORKING ON A CRANK-UP One of the touted advantage s of a cra nk- up is the ability to bring the antennas down to roof or close to ground level where it's easier fo r the station ow ner to work o n it. Fo r this co nve nience, the price th at you pay is the added mechani cal complexity and cost o f the cra nk- up ap paratus. They can co st two to th ree tim es the cost o f a guyed tower of the same height. Ano the r limitation is th e fact tha t a cran k-up cannot be climbed safely o nce it is extended . D o not clim b a crank -up tow er unl ess it is totally nested and locked in the lowered position! Again, all o f the we igh t o f the system is on the cable and pulley syste ms and if so mething breaks o r co mes loose, yo ur to es and fingers are in the plane o f th e tower sections as th ey make their rapid descent. If the tower is jamm ed an d won't come down, don't climb it to fix it. G et a boomtruck o r cran e in to lift you up to wo rk on it. Or, bett er yet, get professional help. It is possible to clim b a crank -up if yo u can lock it int o place. O ne meth od is to use three to four foot long pieces of 2x4's or pip e. In sert them at the bo ttom o f eac h sectio n through th e diagonals and

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they'll catch each secti on before it can move down very far. You can also gently lower th e tower until it rests on the safety pieces, thu s jamming them into place and eliminating any tower mo vement at all. Bob Wilson, N6TV, recommends using U-bolts on a leg per section, again putting th em right under the bottom of a section. E ither way will give you an adde d safety margin . The biggest limitation of a crank -up, in my opinion, is that all of the dead weight of the system plus any added wind loading is all supported only by the cables that hoist the tower up and down. If one of those cables breaks, and occasionally they do, the whole system makes a rapid descent un til it slams into the bottom section or base pad with an incredible amo unt of force. Many times the tower will com e through relatively un scath ed but the boom of the antenna will break in half because of the sudden stop. O nce the cable snaps, you mu st re-cable the tow er to get it back into operation, if you can do it yourself. Modern cran k-up s, such as those made by US TmvER, have a sophisticated system of cables, pulleys, idler wheels, jackscrews and spring-loaded hardware to make their towers move up and down efficiently and safely. Your chances of repairing a cable break on one o f these towers yourself are just about nil.

Crank-up tower cables Crank -up towers depend almos t entirely on their cables to o perate reliably and safely. O ne tower manu facturer, fo r example, wants yo u to rep lace the cab les every 3 years. I have never seen a crank-up cable that needed to be replaced in 3 years, o r even in 10 or 15 years o r mo re in ma ny installations. I call thi s a 'weas el clause', that is if so me th ing happen s to your tower and you haven 't repl aced th e cables wit hin 3 years, th e m anu facturer can weasel out of any liability. You've got to understand tha t tower manufacturing co mpanies are insurance-driven enterprises so they are pr imarily interested in limiting their liability exposure to as little as possible. T hat's why they have po licies like that and they're no t about to give you any information tha t may pot enti ally cau se problems. Here are th e reasons why you ma y want to replace your cab les. 1) D ama ge. This is whe re the cable is kink ed o r flatten ed and it sho uld be pretty obvious. 2) Ru st. This me an s serious ru st, not surface ru st that can be

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easily scraped o ff. 3) Ex cessive broken strands. Most crank-ups use 7x19 galvanized cable wh ich means it has 133 strands in it. You're allowed to have six total broken strands and three in the same bundle befor e it's time to co nsider rep lacing th e cable. W hat you can do to extend th e service life of your cables is to lubricate them once o r twice a year with a cable lubricant . D o not use heavy grease or motor oil. They'll just attract grime and particles out o f th e air. Use a thi n lub ricant such as PreLube which is reco mmend ed by wire ro pe manufacturers and is distribu ted by Champion Radi o Pr oducts (www.championr adio.com) . Also exercise th e cable s by running the tower up and down a co up le of tim es a month and do n't always leave the tower in the same spot all the time , e.g. at th e limit switches. Over time the cable can take a set if it's always at the same place so leaving it at different places spreads the wea r over much more of th e cable.

36 A

FEW FINAL T IPS

O ver the years I' ve picked up many tip s related to tower and antenna construction. Some have been discovered easily; others we re the resu lt o f hard fou ght trial and erro r. I'm pa ssing the se alon g so that yo u might avoid learning them the hard way. (If you have a tip that I've missed, please send it to me for inclusion in the next edition; you'll even get credit for it.) 1. Follow the LXC prime directive. Do wh at th e manufacturer tells you to do; Don't do wha t th ey don't tell you to do. 2. Break every task into bite-sized chunks. In ot he r words, do things o ne at a time and try to avoid doing two o r mor e things at once . An example would be bringing up the co ax feedline alread y att ached to the beam. It adds more weight to the lift, may put the beam out-of-balance, and the cable will typically not go where yo u want it. 3. Look at your safety belt and D-ring when clipping in your lan yard. D o no t assum e that when yo u hear the click that you are secure. Always look.

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4. For most purposes and frequencies, additional coa x connectors, barrels, elbows, etc. in the line will have no significant effect on dB los s or o n S\X!R on HE 5. Don't use chea p hardware sto re electrical tape (i.e. 10 rolls for $1.99). Use only Scotch 33 + or Stip eI' 88. T he se are far superior to anything else. A do ub le wrap of the se high grade electrical tape s is usually sufficient for weatherproofing. Ex pect to pay three to four do llars a roll for th ese excellen t tapes. 6. Always take a roll of tape and a knife or razor knife wh en you climb a tower. 7. If you feel you m ust use CoaxSeal, wrap the joint with tape first. T hen pu t on th e CoaxSeal. Otherwise the CoaxSea/will perm ane ntl y gum everyt hing up. 8. For securing cables ru nning up the tower, use foot-lo ng piece s of solid # 14 or #1 6 insulated wire. J ust twist it aro und the cables and the tower leg; it's mu ch easier to add or remove a cable th an using tie-wrap s o r electrical tape. 9. Never use white tie-wraps; the y'll deteriorate quickly, often in just a year or two. Black tie-wrap s are better but th ey still eventually breakdown . T he best meth od is to cover the tiewrap with electrical tape insuring complete UV protection. 10. W hen removing cable with an axis from a ro ll (i.e. coa x, guy cab le, etc.) , unroll it, don't un coil it. Uncoiling will quite possibly kink it, and will not only damage the cable but also cause you unending aggravation as you att empt to get it unta ngled . 11. Finger -tight connections are no t good eno ugh. Use one pair of pliers o r Channel-Locks to ho ld the co nnecto r and another pair to tighten them. 12. When putting up tu bu lar leg towers (ROH N 25G, 45G etc.), always grease the in side of the bo ttom legs. T hey'll go on more easily and the grease will retard corrosion growth that makes taking th em apart difficult. Also, if they are new towe r sections, inspect the bottom of the tower legs and the bolt

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hole s for excess galvanizing flash. U se a tap er punch (drift pin) to clear th e slag. Be careful not to enlarge th e bolt holes. 13. When installing a ro tator, point the rotator North (o r ano ther kn own directio n) after testing o n the ground to make beam alignme nt easier o n the towe r. 14. \'{fhen hauling up ro tato r cable with th e rotator, tie a big loop in th e cable about three-feet below th e ro tato r, then clip th e loop to a carabin er on th e rotator hau l line to take the weight off the terminals. A large gentle loop won't damage th e cable. 15. Never use eyebol ts that have eyes that can open. Always use eyebolts tha t are cast or welded clo sed. 16. Leave thre e to fou r-feet of m ast extending above the top of the highest antenna on the tower. This extra m ast can then be used as a gin pole/ pu lley attac hment point for other antenna or tower wo rk. 17. U se only stainless o r galvanized hard ware. Avoid cadm ium plated, etc. If you're not sure , leave th e suspe ct hardwar e o utside for a few weeks and see what happen s. If it starts to ru st, find some o the r use for it, far away from your tower. 18. Do not use machine sho p type pillow-block s for thrust bearings. These are the type which use Allen screws or set screws to secure th e mast. T hey loo k like th ey'll work and they're relatively cheap bu t they will rus t solid in three to five years. Use only outdoor grade (ROH , galvanized, etc.) thrust bearings if you plan to ever take it apart again. 19. Use antioxidants on your me tal-to -metal cont acts. There are products for copper and alumi num. Use the co pp er ones o n your ground system and use the alumin um ones when assembling yo ur bea m ante nnas. 20. Use a file to rou nd the sharp edges of all plates, steps, brackets, arms, etc. to keep th em fro m damag ing you. 21. Always take extra hardware, nuts and bolt s up the tower with you in case you ru n sho rt or drop some th ing. If you don't have them, you'll invariab ly nee d them. 22. Use a pigtail on beam s fro m the feedpoint to a co nven ien t point wit hin easy reach o f the ma st. D o no t attach the coax to the beam o n the gro und and haul up togeth er with an-

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tenna. It'll invariably be on the wrong side of some thing. 23. Avoid splitting th e end of the coax to feed th e ant enna (ala CUSHCRAFf and TELREx) if possible. Use dipole cen ter ins ulator so th at yo u can use a PL-259 instead. This will pr event water fro m wicking down th e coa x. 24. Tigh ten all co nnectio ns again the next day. N ut and bolt mechanical connections will loo sen up the first time th ey go th rough a temperature cycle. 25. Fo r a simple drip loop o n your coax, take a medium sized tie wrap and attach it to th e coax entry loop just befor e it m akes your building entry. Point the tie wrap tail down and you have a quick and dir ty drip loop. 26. An ante nna sho uld be removed the same way it was installed. If it went up with a crane, it' ll probably have to be rem oved by a crane . 27. When putting something together " tem po rarily", always install it as though you won't be coming back; temporary so metimes means it'll be up and used fo r years. 28. What if you're considering a full-sized three-element 40m eter beam? You'll need a bigger tower, bigger rotator, bigger rigging talents and a bigger budget. H ere's an alternative; stack two CUSHCRAFf 40 -2CD's or XJ\tf240's. Smaller rotator, smaller hardware, smaller cost but similar gain and performanc e to the much bigger and m ore cos tly antenna . 29. If th e wind is blowing while you're up on th e tower, it m ay be difficult to lower the end of the rope to th e ground. The first thing you can do is to attach a weight to the end of th e rope; a wrenc h wo rks well. Pro fessional clim bers use a bea nbag with a loop o n it that's full of m etal sho t. If added weight isn't enough, clip th e en d of the haul rope carabiner into the other side of the rope. The cara biner will slide down the ro pe whe n it's lowered. You may want to also use a weight but just using a carabiner will work 90% of th e time . 30. Some ro tators have control cab le quick disconne cts, others don't. If you wan t to add a quic k disconnect featur e, th e easies t th ing to do is to use trailer plugs - they co me in a flat 4-wire polarized con figu ratio n. Get 2 sets and install one set in one direction and th e other in the o ther direc tio n. T his will

242

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roWER

res ult in the po larized plugs being in opposite directions, preve nting accidental plugging into the wrong wires . 31. One way to keep rotator control cable colors straight and co nsiste nt is to use the resistor color-code. It is: black, brown, red, orange, yellow, green, blue, violet, grey and wh ite. 32. Antenna element hose clamps invariably catc h on anything wire an tennas, guy wires, cables, etc. To minimize this annoying cha rac teristic, wrap th e hose clamp with a layer or two o f elect rical tape .

INDEX 6G-55G

Building departm ent: 10, 33, 44, 48,49, 50,51, 52, 53, 55, 58, 134, 198,206 BX towe r: 16,1 7,1 8, 75, 85, 98, 105,1 26, 211

6G : 17 20G: 17 25G: 15, 16, 17, 20,22,26,60, 74,75,85,88, 92, 98, 114, 124,15 1,1 81, 206,210,21 2, 214, 233,239 45G: 17, 20, 22,60, 75,93,98, 114,1 24,1 81,206, 210, 212, 214,233,239 55G:20,22,23, 114

A A.B. Chance Co.: 69 AA20W: 14 Alfaspid: 152, 154 Alliance HD73: 150 Aluminum tower: 13, 18, 222 AN Wireless: 17, 19 Anchor bolt s: 63,70,76,77 Antenna analyzer: 95, 98 Antenna stack: 22, 23, 119, 128, 151,1 52, 227, 241 Antioxida nt: 65, 66, 67, 124, 149,1 80, 207, 209, 213, 228, 240 ARRL (American Radio Relay League): 29, 38, 39, 40, 44, 47, 49, 50,51 ,1 20, 132,226

B Balun: 141, 148, 207, 208, 230 Basket hitch: 104 Big Bertha: 24 Bowline: 106, 110, 111

c Cable clamp s: 62, 115, 116, 117, 122 Cadwe ld: 180, 181 Carabiner: 62, 84,90, 95,99, 101,1 02,103,104,105,106, 110,11 2,127, 128,158,160, 240,241 CATS RD -l100: 151 CC&R's (Covenants, Conditions & Restrictions): 41,46 Champ ion Radio Products: 84, 99, 121, 126, 134, 147, 188, 228, 237 Chimney: 14, 15,26 Choker: 103, 104,126,127,1 57, 160 Clevis (see shackle): Clove hitch : 111 CoaxSeal: 147,239 Co ld galvanizing: 66, 135, 211, 213,214 Come-along: 77, 90, 95, 96, 105, 111, 112, 120, 125, 126, 127, 161,1 78 Conc rete: 15, 18, 24, 28, 51,52, 53, 70, 71, 74, 75, 76, 77, 79, 127, 17 1, 172, 176,212,214, 215,222

244

Up THF; TOWER

Concrete pumper: 76 Crane: 18, 19, 159, 218, 220, 233,234, 235,241 Crank- up tower: 17, 18, 20, 21, 22, 51,74,75,76,206,209, 210,21 1,215,216,235,236, 237 Create rotator: 152, 154

H BX towe r: 17 HDBX to wer: 17 Heights Towe r Systems: 18 Heliax: 142, 182 He licopte r: 43, 159 Ho usebracket: 20 Hy-Gain CD45: 150 H y-G ain H AM IV: 1228, 151, 154, 201 Hy-Gain HDR-300: 151

D Delhi tower: 18 Di llon dynamometer: 121, 122

Hy-Gai n TailTwister (f2X) : 151, 154,1 56, 201 Hy-GainTR44: 150

E Effective Mo ment: 155 E levated guy anchor: 78, 79 E moto rotato r: 152

I I.CE. (Industrial Comm unications Engineers): 179,1 84

F FAA (Federal Aviation Agency): 27,28,43,49 Fall arrest harness: 14,57,82, 84,90 Fall arrest lanyard: 57,82,83,85, 87 Figure 8 knot: 84, 111 Form: 70,71,77

Imp act hammer: 71 Installing mast: 126, 127

K KOXG: 24, 152 KlTD:40 K3LR: 222,226 K4VX: 120 K5IU: 24

G

K6l'vIYC: 151 K7FR: 141 K7PN :24

G inpo le: 7,22, 23,95,98,99, 124,1 25,1 26,1 27, 203, 220 Gorilla hook (see rebar hook):

K7RA:26 K9YC: 164 K-Fac tor: 155

Gravity mo unt: 15 Green Heron: 154 Ground ro d: 170, 171, 172, 173, 179, 180, 181

Klein cable grip: 96, 120

L

H Hand grinder: 73, 74, 85, 95, 97, 119,233

Leather safety equipment: 82 Lightning dissipater: 185

I ND EX

245

Loo s guy wire tcn sion er: 95, 121,122

Positioning lanyard: 82, 83, 84, 85,87

LXC Prime Directi ve: 22, 34, 238

Po sitive pu ll-do wn : 21 PRB -1: 29, 30, 35, 36,37, 38,44, 46,48

M MARC (Mast, Ante nna,

Pre formed guy grip: 79, 115, 117,11 8,11 9,120,21 4

and Ro tator Calculator): 134

PreLub e: 216, 237

MOY: 182,1 84, 185

Prop pitch: 153, 154,209 Pro sistel Big Bo y: 152, 154

N

N6 T V: 236

Pu lley: 20, 95,99, 100, 102, 103, 106, 124, 125,154, 159, 160, 161,162,163,193,1 94, 198, 199, 203, 205, 21 1, 215, 216, 235,236, 240

N 7YYG : 19

Pu sh-up m ast: 13

N OAX: 188,227 N 2AA: 59 N 6BT : 158

N8 DJ B: 151 NA I L: 29

R Rebar: 51, 70, 73, 74, 75, 76, 77, 96, 105,171, 222

N ational Electrical Co de (NEC) : 172,1 77

Reb ar cage: 73, 74,75,77, 171, 179

N D8L: 221, 226

Rebar ho ok: 105

o

RG -213: 139, 140, 142, 144, 145

Orion 2800: 129, 133, 152, 154

RG -8: 130, 138, 139, 140,141, 142,144,145,1 82,230

O SH A: 8, 57, 81, 82, 84, 85, 102,1 03,1 05,

Ring rotator: 152

O verhand knot: 110, 111, 112, 128,199

Rivet s: 17,229 Roof-m o unt ed towe r: 14, 15, 26 Rotating tower: 23, 24

p PE (Pro fessio nal Engineer): 22, 51, 75 Phi llvstran: 24, 115, 117, 118, 119,1 20,1 22,1 81 Pipe: 13, 15,61 ,62, 78,79,96, 99, 119, 124, 131, 132, 133, 144,169,1 70,1 73,200,202, 203 , 222, 235 Polvphaser: 179,1 81,1 84

Rust: 18, 62, 64, 66, 74, 93, 114, 135,1 56, 209, 210, 211, 213, 214,215 ,21 7, 232,233,236, 240

s Scotch Super 33+ tape: 146,1 47, 239

246

Up TH E TOWER

Scotch Super 88 tape: 146, 147, 239 ScotchKo te: 148 Screw earth anchor : 79 Self-sup porting tower: 17, 18, 19, 20,24, 69, 70, 71, 74, 77, 158,21 1,214 Shackle: 62, 79, 102, 112, 118, 122, 160, 214 Sling: 74,90,95,99, 101, 102, 103, 104, 105, 106, 120, 125, 126,1 57,1 58, 160,1 61,1 91, 200,203,205, 234 Snatch block: 99, 100, 105, 125, 162 Soil test: 52 Spaulding: 16, 18 SPGS (Single Point Ground System) : 175, 176, 182, 184 SSV tower: 17, 18, 19 Star bracket: 80 Super Titan tower: 19 Surge protector: 173, 182, 184

T TEK screws: 229 Thimble: 62, 79, 115, 116, 118 Thrust bearing: 93, 127, 128, 129,1 33, 155, 156, 240 TIA-222:5 1,52, 79, 134, 214 T itan tower: 19,98

Tor que arms : 60,79,80, 158 To\verJack: 126, 233 TowerTalk: 89, 188 Trucker 's hitch: 111, 112 Tub ing: 61,62,96,132, 133, 135, 148

u UBC (Unifo rm Building Code): 48, 49, 50, 51, 52 Ufer ground: 171, 172, 176 Unde rground utilities: 41, 71, 143 Universal Manufacturing : 18, 222

v Volunteer Counsel : 40, 49

W W3AS : 189 W3LPL: 7, 144, 222 W3TX:24 W6NL: 132,207,229 W7NI: 91 W7RM:7,27 W7WVF: 19 W7ZR/XE2DV: 23 Windload: 23, 134 Wooden po les: 12, 13 Yaesu G450XL: 150