On Wed, 7 Apr 1999 08:12:19 -0500 (CDT), you wrote:
>Well I'll take your word on it. So now....what to do. I in the process of
>installing a 110-120ft 25g tower but I'm not sure what to do with the top
>set of guys. Fiberglass is out. I been read the past few sets of threads
>on diffent guy materials and it seems there are a few options. Which on is
>the best though. I purchased enough guy wire for the entire instalations.
>should I break up the top set with the porcelain insulator type or is their
>some combination of Philis. and insulators that is better? Your thoughts on
>this would be greatly appreciated.
Remembering that the only element on a yagi which is actually resonant
at the operating frequency is the driven element (all the others are
long or short)...
If you are only going to have 20/15/10 at the top, then break them up
into non-resonant. IF, however, you intend to do 30/18/12 along with
that, there is no "non-resonant" length that will not at least mess up
the f/s or f/b, or create an unfortunate null, on one of the bands.
In the 30 thru 10 case, as a minimum the models infer using
phily/fiberglass as guys on anything within a 1/2 wave on the lowest
freq in use up there. Convert the phily to steel at a lower level.
If you plan to use stacks on that tower, you might as well bite the
bullet and plan to sell most of your steel guy line. Guys are awful
hard to change once all the stuff is in the air.
Best 'o luck.
Guy
>KK5LC
>Shane Dugas
>Prairieville, LA
>Shane@eatel.net
73, Guy
--. .-..
Guy Olinger, K2AV
k2av@qsl.net
Apex, NC, USA
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