>Why is the output low on the higher frequencies? I agree with Carl that it
>often is a sign, but I fail to understand why. If the peak cathode current
>is available on 80m to give full output, why isn't it there on 10? I guess
>one could assume that if the gm is going down, the input impedance will
>change, but that should be seen on the other bands as well. Might be
>interesting to do an input SWR measurement with old tubes, then substitute
>new ones and see if there's a difference.
This is a question I am having too. My 4-1000A puts out several hundred
less watts on 10 meters than on 80 (1000 on 10 vs. 1700 on 80). Does the
gain of the tube drop from 80 to 10 meters that much (7 dB)? Or are
there other design problems in the amp.
Tom Rauch was saying something about the matching network's ability to
supress the third harmonic. If you read this, Tom, I would like a more
in depth technical explanation as to why this is.
73,
Jon
KE9NA
--------------------------------------------------------------------------
Jon Ogden
jono@webspun.com
www.qsl.net/ke9na
"A life lived in fear is a life half lived."
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