I've finally gotten all of the bugs out of my SB-1000 and made various
improvements.
I added vacuum-relay QSK and replaced the parasitic supressor (thanks, Rich),
put in
a soft-start circuit, added a glitch resistor (thanks, Carl), replaced the plate
choke with an Ameritron AL80B part (thanks to several who suggested this). I
replaced the arc-damaged band switch contacts for the 160-meter padder and
added a
corona washer (thanks, Tom) to prevent a recurrence of this.
The guy who originally built this amp got bored or something when he got to the
plate
circuit, because he did a lousy job (it's funny that the rest of the amp seems
to be
built carefully). I completely redid it, and while I was at it replaced the
leads
from the switch to the coil with 1/4" strap. I made sure all grounds were good.
When I got done, I found that my input SWR problems on 17 meters had gone away!
I
now get full output on all bands (800 watts CW, maybe a little less on 10
meters),
including 18 and 24 mHz. I haven't blown any fuses or heard any arcs.
Thanks again to anyone who I didn't mention who answered my numerous posts
asking for
help.
Vic, K2VCO
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