Tuned up the SB220 last night (Hasn't been inline for a week or so).
Everything as normal.
Flip grid current meter to grid, key the exciter, PINNED (Guess I'm doing
back to back diodes today :) ) Unkey, it lightly pins reverse... Almost
didn't notice it.
Look inside, nothing "glowing", everything looks normal.
Turn it back on, try it one more time, same thing..... I tried SSB, and
keydown, no drive I had a third to half scale positive grid I.... ANY
amount of drive will cause it to pin, HARD.
The zener has been replaced with a string of 5408s and a largish cap about
10 years ago. I have had a spat of bad caps in this amp.
Haven't ripped into it, just shut it off last night and went to bed..
Bummer, 80 was open across the US.
Thanks, in advance.
--Shane
KD6VXI
--
It's a sad state of affairs when your tubes don't have handles but your
dummy load does.
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