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Tower Guy's

B

Blue Jay

W9WDX Amateur Radio Club Member
Nov 16, 2008
114
10
28
77
Central Ohio
I live in the middle of 5 acres of woods with 75 to 80' trees. Getting ready to put up 80' of tower to get my 2M & 70CM antennas above the trees so I can get a dicent signal to the local repeaters, 12 miles to the 2M and about 23 miles to the 70CM. Do I need to worry about the length of the guy wires holding the tower? If so what length to avoid.
Thanks
 

avoid lengths that are the same as the distance from the guy point on the tower to the ground...I think about 20% longer?
 
At those frequencies, you will definitely have to worry about db loss. VHF/UHF are notorious for losing a great deal of signal on both TX and RX. I would only put it up no more than 30 ft up and run the best, shortest piece of coax that money could buy. NMO connectors on the antenna/feedpoint end.
Just the facts...
 
To answer the question. No, I don't think I'd worry about the guy wire lengths as far as being resonant, or signal robbers.
- 'Doc
 
Kewl...80' tower :) Get a HF yagi up there if you can too. :) :) You'll have a kick ass 2m signal at that height, too...although you'll probably want to invest in some good coax.

Are you worried about guys being resonant or is the question about structural integrity?
 
I think you should break up the guy wires so they don't become part of the system. As a reference William Orr recommended 6' lengths (between insulators) for the 11m band in a couple of his books
 
Lets see, for 70cm, that'd be about 6 inches. Lots of insulators! For 2 meters that'd be about 19 inches, not quite so many insulators. About 680 of'em for 70 cm, only about 215 for 2 meters. That's assuming just three guys at the 80 foot level. Figure thimbles and maybe 8 inches of overlap length per insulator, and at least 4 clamps for each insulator. What's that, maybe a nile and a half of guy cable, about 300 pounds of clamps, insulators and thimbles. Hope he's got a long bed heavy half ton to haul that stuff, sure don't wanna think about the shipping.
Or just do it the easy way. Put them 2 meter and 70 cm antennas on a 10 foot pole out of the top of the tower, and don't worry about it.
- 'Doc


HF is a lot easier with them insulators and stuff.
 
Never mind
I should have read a little more I just saw the HF part above
The sarcastic guy is right

Just trying to helpful
 
I was just reading on the other thread that the guy anchor point should be 80% of the height away from the base. So an 80 foot tower would have 3 guy anchors 64 feet away from the base. I would probably run at least two sets of guy wires.
 
Thanks for the replies, the concern I had was if they would be resonant or not. It will have guy's at 3 levels (30', 50' & 70') my 60+ brain does not like much movement at that height and yes it will have a 5 element and a super jay pole up on top with LMR 400 coax.
 
Is this a J-pole kit that you are talking about? One bit of advice I would want to share with you. Make the J-pole tuned up on a short pole before you get it up to the top of your tower. Otherwise, you may drive yourself crazy taking it down off of that 80 ft tower - having to do a "back 'n forth" because it hasn't been tuned first. J-poles may be cheap and work - but only after a lot of fussy adjustments - first...

If I were to have a 80 ft tower, I would get a Comet or a Diamond antenna w/NMO connector. That would be a set it up and forget about it kind of job - because they work right out of the box - no mess no fuss.
Just thinking out loud...
 
Yes it is already tuned, had it on the end of the house for a week and it is now at 50' on the TV tower, that did help the signal some and at 146.6 sw meter just barely moves and is at 1.6-1 max on the end of the band.
 
Well...

At 80 ft height...you should hit both those 2 meter and 70 cm repeaters easily..

Do not worry about the guys being resonant..
Do not simply put a J Pole up .. Do get a Comet or Diamond to put up there..
Do use really good coax ( maybe even hardline given the likelihood of going more then 100 ft )
 
C2 said:
I was just reading on the other thread that the guy anchor point should be 80% of the height away from the base. So an 80 foot tower would have 3 guy anchors 64 feet away from the base. I would probably run at least two sets of guy wires.
Click to expand...


The other thread is wrong then. The industry standard is 2/3 of the guy height,or 67%
 

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