> Thanks for the response. I don't exactly understand it fully,
> where you are making a reference to a design flaw, or its one of those
> things you have to live with when you ad a Tuner in the configuration.
It is a design shortfall, rather than a flaw. It is juts one of those things
that misses you when you test on dummy loads or look at circuits on paper.
I actually had the same errors in my designs, and discovered them in similar
conditions. The result is I had to add a second low-pass decoupling cicuit
in the feedback path of a PIN swicth I designed, that would correct a gain
peak in the original lowpass circuit.
> It does look like from my explanation I found the problem and resolved
> it in my own way or confirmed your findings.
It drove the W4 nuts also, because when he moved his tuner from the antenna
area into the house his signal suddenly had a wide hissing noise and bad key
clicks.
The only reason I found it so quickly in his PA is because I had the same
thing happen in mine. The problem is aggravated by manufacturers using
oversized coupling capacitors.
73 Tom
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