I had a problem with efficiency on 160M on a newly constructed
amp. (yc 156)
I want to thank all those who responded both on the reflector and
privately.
Symptoms were: Tank appears resonant on 160M
80M - 15M worked fine
With 5k in on 160 I could only get
1200 watts out
Yesterday I added 1600pf (4 doorknobs) to the base of the plate
choke and noticed a
significant change in output as well as stability. It seems the larger
metal tubes
require more bypassing than found in some of the other designs.
Thanks for all the input.
73
Lynn NO9Z
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