> Date: Mon, 27 Apr 1998 11:14:06 -0400
> From: "J.P. Kleinhaus" <firstname.lastname@example.org>
> Subject: Re: [TowerTalk] Breaking up guys
> To: email@example.com
> Cc: firstname.lastname@example.org
> Hi Tom:
> One of the suggestions I received was to model the whole sucker
> with EZNEC or a similar program. If there is no current on
> the guys, then I'm cool.
That's true. If there is *no* current there is no radiation. But
keep in mind *small* radiation effects can, under the right
conditions, add up to a large combined effect.
How would you model the wire loops through the insulators? As loads
of a certain capacitance (that's all I can think of doing!)? If so,
I would think it is very important to include the effects of the wire
loops at the ends, especially with longer guy line sections!
> I understand your comment about non-resonant lengths re-radiating.
> Most of the suggestions received are pointing to breaking up the
> guys in shorter, not longer lengths. Some even go so far as to break
> the guys every 12 feet close to the tower and then increase the
> spacing from there as you get farther away. I guess that's the
> ultimate solution to guarantee the minimum interaction.
That's what I do, always trying to keep the wires shorter than 1/8 wl
on the band of interest when within 1/2 wl of the antenna.
502 D insulators are only $2.25 each brand new from Porcelean
Products, and 1/4 inch preforms are much less than $2.00 (I've
found them as cheap as $.79 each in bulk) from utility supply houses.
EHS 1/4 inch guy line is a few cents a foot from utility suppliers
(yes, they sell EHS if you ask..as well as lower strength grades).
73, Tom W8JI
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