>
>Typical amateur amps are actually rather modestly shielded at
>VHF. They rely heavily on low impedance on the anode and
>cathode of the tube to hold direct VHF radiation on TV channels to
>a minimum.
I thought that most of the TVI reduction came from the low pass action of
the tank circuit. Or are we saying the same thing?
>If the cap was "parallel resonant" with a high impedance, the amp
>would likely be a nightmare in many ways.
Tom, help me understand something here. One of the things that can cause
an amp to oscillate is a low impedance path from the anode to ground. If
a high impedance is introduced at the resonant frequency it can prevent
the oscillations from occuring. This is definitely what I believe I've
done with my amp and I have no nichrome in the anode and no resonant dip
at 80 MHz (typical for 4-1K) either. So help me reconcile your statement
and my experience.
73,
Jon
KE9NA
--------------------------------------------------------------------------
The Second Amendment is NOT about duck hunting!
Jon Ogden
jono@enteract.com
www.qsl.net/ke9na
"A life lived in fear is a life half lived."
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