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Larry W4CSC
 
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Default wrapping ssb antenna on kevlar backstay

Bruce in Alaska wrote in
:

day. A good compromise would seem to be a resonate 1/4 Wave at say
3200 Khz would allow for far efficency at 2182 Khz, by wrapping the
helical windings tighter at the top of the antenna, give a reasonable
length of wire on the lower part to resonate with the tuner at 12 Mhz,
16 Mhz, and 22 Mhz.

Bruce in alaska


I like the idea of the Kevlar as an insulator. But, instead of making it
into some kind of untuned RF choke, why don't we make it into a TRAP SLOPER
vertical by putting traps on the Kevlar, interconnected by straight
conductors, for the upper bands, above the natural resonant length of the
whole distance from feedpoint to mast, THEN use the tuner when the length
of the backstay becomes too short.

The coils in the traps will lower the natural resonant frequency below a
straight backstay. The trap capacitors are too small to be significant at
the low frequency bands. Below the natural resonance, the traps act like
loading coils for the tuner, drawing more antenna CURRENT up the too-short
radiator, which is never bad for good radiation.

On any marine or ham band the traps are set up for, no tuner will be
required and a resonant antenna is always a better radiator than this
stupid old marine base-loaded clothes line or flagpole we're using, now.

Larry
Above 40 meters, you could leave the lossy tuner in THRU....(c;