Thanks for comments and suggestions
Rich, I will work on the amp. this weekend if I have the time and let you know
how things improve.
Is damping the cathode with 10R/30pf equally as good as eg. 10R i series with
the drive?.
FYI Jon, the signal were single tone carrier with 300W out (lowest possible
drive).
So no compression or IMD. Didn't try at much higher power levels. It all looked
the
same.
John, thanks for the comments on the test setup and measurement techniques.
I decided to make these provisional measurements because of the problem
with the "poor efficiency".
I will certainly make more thorough measurements taking into account you notes.
However I don't think the spectrum analyzer was overloaded, signal max. was
appx. -30dBm.
I will make a notch-filter to filter out the fundamental frequency and use the
directional coupler
for the next step.
I will get back with more information whether the high frequency signals are
harmonic related.
I only used high speed keying on 80m tying to find some instability. All other
measurements
were made with continuous carrier.
talk to you guys later
73 de Soeren, OZ1FTU
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