Hi Mark,
> I have a copy of the Antenna Handbook, but would like to know current
trends
> in non-resonant guy lengths. My guys will be about 55' long. Should I
have
> about 3' at the top, then an insulator, then 14', then 14', then 27',
then
> insulator, then anchor? Is this safe for 14, 21, 28 MHz?
I'm not sure the Handbook or programs that calculate this stuff allows for
capacitance of wire loops through the insulators. Does anyone know for sure
if they do?
If programs, length graphs, or calculations don't (and I'd bet most or all
don't) , that will mean big resonant frequency errors for higher
frequencies with multiple guy sections.
I've always meant to measure resonance in a real guy line (I sure have
enough of them), but never got a round tuit. I not only avoid ANY length
near resonance, but also any length longer than 1/2 wl on active bands for
a considerable distance away from the antenna.
> Does everyone use 504 insulators, or 502? I can get 504's from my local
> electrical supplier for only $4.55 each. I will be using 1/4" guy wire.
> Should I use "genuine" Rohn 1/4CCF clamps (forged, hot dipped) or are the
> malleable ones OK?
I use 502's, they are heavy enough! I also use EHS grips from a local
utility supplier. Grips are a lot cheaper than clamps, and faster. They
have the same rated strength as EHS guy line. I paid about $3 for
insulators and $1.65 each for grips, and $.09 per foot for 1/4 inch EHS my
last purchase. Excellent quality parts.
Just be sure you ask for specs when you buy the parts.
73 Tom
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