Ah, 'well, yes that goes without saying' to quote Dr. Franken-stein. But of
course anytime you put beams up the side of a tower and rotate them you have to
take into account the guy wires hitting the boom or elements. Of course, if
it's a stand alone tower this does not come into play. Just something you have
to deal with. But I still want do it and I've even though of using a 2 element
quad on my particular setup. I like quads and know I can build another one.
Tuning can be a chore. But I don't know why there aren't more of them. They
work.
But yes, make sure whatever antenna you put up doesn't contact the guys...
Terry
KI7M
> On December 5, 2018 at 8:54 AM "Bob Shohet, KQ2M" <kq2m@kq2m.com> wrote:
>
>
> For various terrain and property line related reasons I have had to go
> shorter than and significantly longer than the 80% with specific legs of my
> two towers, as short as 65% and as long as 130%. This also has an effect on
> the tensioning of the guy wires – and which needs to be taken into account.
>
> What is often not realized until after the fact is that if your intention is
> to stack multiple antennas and rotate them separately, either on sidemounts
> or ring rotors, using less than ~ 80% may compromise or eliminate your
> ability to stack and rotate the “in-between” antennas because they will
> likely get caught in the guy wires. And, if there is not enough extra
> clearance, even if you can safely rotate under the guy wires on a calm day,
> on a day when it is windy or icy or both, you might not clear those same guy
> wires! It is quite remarkable to see just how much those guy wires can move
> and bounce around in violent T-storm or worse!
>
> Depending on the band, length of the boom and elements, proposed height of
> the antenna, heights of the guy wire attachment points and proximity to the
> antenna, radius of antenna (mounted on the rotator) from the tower legs
> (especially if side-mounted) and other factors, 80% may not be enough either;
> but it will at least get you “in the ballpark” and give you some viable
> options.
>
> 73
>
> Bob KQ2M
>
>
> From: Grant Saviers
> Sent: Wednesday, December 05, 2018 11:17 AM
> To: cqtestk4xs@aol.com ; towertalk@contesting.com
> Subject: Re: [TowerTalk] guying distance
>
> Except that a PE can change this with the proper analysis. Also, a post
> plus deadman end is a way to geometrically shorten the 80%. Look at
> commercial guyed towers and they often have a shorter guy anchor to base
> perecent (ie steeper guy angles).
>
> Grant KZ1W
>
> On 12/5/2018 7:42 AM, Bill via TowerTalk wrote:
> > Rohn specifies 80% of the height for their towers..25, 45, 55, 65 all the
> > same.
> > Bill K4XS/KH7XS
> > _______________________________________________
> >
> >
> >
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> >
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