Stan - For about 8 years, up until this past spring, my shunt fed tower
for 160 had a KT34XA (insulated elements, later upgraded to a KT36XA same
insulated elements) at the top and I never experienced any issue at all
running 1500 watts, even during a few contests where, as you know, you are
running "continuous" for an extended period. I've read discussion about
whether the coax should run inside -vs- outside the tower, mine ran
outside.
The current arrangement (same tower) has a Cushcraft 40 mtr beam
(insulated DE) and an A3WS (insulated DE) on it and the feedlines now run
inside the tower. I have developed a problem on 17 meters (12 mtr still
OK) with the A3WS so I am trying to assess if it is something caused by
the 160 meter shunt feeding or other cause. Still resovling that.
But, for years no problem with original set up and now no issue except as
noted on 17 meter but most likely NOT related to shunt feed & high power.
I know some folks have experienced issues but to date (thankfully) I have
not.
73 Joel W5ZN
> I have never had an issue with this on any tower I have shunt fed that had
> a Yagi at the top with insulated elements, but then again my insulators
> are
> probably a lot better than the average ones used on commerical antennas.
> I
> am thinking about shunt feeding a tower that is not mine and wanted to
> know
> whether anyone has had any issue runniing 1500 watts to a shunt fed tower
> that has a Yagi at the top with insulated elements. Im not wanting to
> ground elements and don't need additional top loading. What I would like
> to know is anyone has done any damage or melted anything.
>
> Thanks...Stan, K5GO
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