[Amps] SB-220 WARC bands

[Bert Almemo]

Thanks for all your answers and shared experiences re. my problem running my
SB-220 on the WARC-bands. All of your amps seem to be doing fine, but
unfortunately not mine.

Power out on 12 and 17m is around 400W and 30m doesn't really work at all.
The reason for the low output, compared to all of you who answered (most of
you have over 1KW out), I don't know. Are the tubes tired or do I have too
little driving power. The IC-765 only delivers 90-100W and that, I know, is
not enough to drive 2x3-500Z to full output. The output from the amp is
anywhere from 600-900W depending on band, 10-80M.

Any ideas of how to find out if the amp is healthy, tubes OK, etc?
Appreciate your input.

73 Bert, VE3OBU