At 11:09 PM 1/31/97 -0500, Larry Higgins wrote:
>I tried coax stubs several years ago. RG8 worked fine on the exciter.
>When I fired up the amp there was a blinding flash at the base of the
>tower. The RG8 had metamorphosed into charcoal. The coax was foam
>dielectric; never thought of using teflon coax; that sounds like a great
>idea, and it's proven.
>
Another viewpoint: I used to use coax stubs as capacitors but stopped
doing so after I made some measurements which showed significant
resistive loss (several ohms) in long stubs using RG 213. I never
fried any lines but the idea of tolerating any loss in a vertical antenna
system did not appeal to me. The teflon dielectric lines or hardline
would probably be better although I haven't measured any. Since the
loss tends to decrease with shorter lengths, using coax for short stubs
is probably OK, however.
73, John W1FV
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