>Interesting. Since the cathode is not the major player in VHF
>oscillations in traditional GG amps, I wonder how de-Q'ing the
>cathode would stabilize the PA?? Or are you talking about HF
>oscillations, that occur in tubes with large amounts of feedback
>capacitance at HF?
Could have been an HF oscillation for all I know as I didn't have a freq
counter at the time to measure them. I guess I could have used my
MFJ-259 but didn't think about that until now! Needless to say, without
the series RC suppressors on the cathode, when keyed with zero drive and
as the tune C was reduce to minimum, the grid and anode currents would
increase. Putting the RC networks in, eliminated this problem. Wether
it was HF or VHF, I can't say, but regardless the tube was stabilized.
73,
Jon
KE9NA
ps: OK, now don't bother us for another year! :-) - just kidding!
-------------------------------------
Jon Ogden
KE9NA
http://www.qsl.net/ke9na <--- CHECK IT OUT! It's been updated!!!!!
"A life lived in fear is a life half lived."
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