> >Rich, the problem with getting old and having a number of amplifiers is that
> >I sometimes forget what I have. My wife claims I have too much stuff. But
> >your comment reminded me that I do have a Collins 30S-1 amplifier. It does
> >not have parasitic suppressors.
>
I do not have all of the editions, but it was after the fifteenth edition of
Bill Orr's
Handbook that parasitic suppressors started appearing on ceramic tube amp
projects therein. There are even projects in the fifteenth edition that have no
suppressors on 4-250A/4-400A tubes. Somewhere between the sixteenth and
twentieth editions did suppressors appear on all amp project articles. This
includes a few 8877 articles that had no suppression devices.
My guess is that things became progressively squirrelly as we added 160m and
WARC bands, and especially as anode voltages increased above 2500-2700 volts
to 4000 volts on the 8877 and other tubes. Also, the "miniaturization" of amps
from large racks to bread-box size played a part in this.
(((73)))
Phil, K5PC
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