Thanks to the speed course "SB220 Fundamentals 101" from new friends in
this list, I rationalized that I knew enough to buy the amp. The seller,
being a personal friend in my local radio club, allowed a three hour
test session at his station. We produced output of 1200+ watts in SSB
mode with CW drive (as an upper bound test case) on 80, 15, and 10, and
about 800 watts on 40 and 20. This was with plate current and grid
current within tuneup guidelines in the book. The power did not droop
significantly while key-down, and there was only moderate red glow of
the tubes. I don't know why the lower power on the middle bands, but
since the power on both ends was good, I made the assumption that this
is a matter of more careful tuning, or input network tweaking, etc. I'd
welcome any comments about this.
Anyway, thanks again for all the useful information and encouragement.
73 -
Bill N7DZ
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