Jonathan Kaplan wrote:
>
> I took tthe sugeestion that I run a test on SWRs for
> all frequencies, both with and without the Amp on. Here's
> what I found--
<snipped>
Yes, the 40m dipole is buggered. Maybe the coax is open or shorted at the top.
The SWR's are almost always higher with the amp on -- that suggests to me that
the amp is generating lots of harmonic output, which results in more reflected
power because the antenna is not matched as well at the harmonic frequencies as
at the fundamental. But how do we explain the lower swr with the amp on the hgh
end of 20 meters? Well, note the swr on 10 -- the second harmonic of 20 -- it's
quite low! So I conclude that for some reason, possibly the way you are tuning
or driving the amp, it's output has a large harmonic content. Make sure you are
tuning and loading it according to the manual, and that your grid current is not
excessive.
73,
Vic, K2VCO
Fresno CA
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