>As a gift, I received a Knight T-175 Linear Amplifier. I found it
>listed in an old 1969 Allied Radio Catalog. It uses a pair of 6JE6A's,
>connected in parallel. It was intended for 6 & 10 meter operation, 300
>Watt output SSB, 150W CW, & 120W AM. Any others out there and still in
>use?
Kinda nice!
>
>What has me puzzled is its published Class of operation: B(2) grounded
>grid, triode connected. However, my reference books list Class B as
>push-pull. Am I reading them wrong? Any insight or comments? They
>would be appreciated.
Are you sure the tubes are paralled or are they offset by 180 degrees?
In reality, I think you could do it both ways and still have Class B
bias. A single tube running Class B GG is very possible. So you could
do it with two tubes running parallel and in phase. A very common
approach though when running two tube AB or B class amps is to offset
them in phase 180 degrees so when one device is off the other is on. I'd
bet you probably get a slightly cleaner signal this way although it adds
to the circuit complexity having to add a wide band 180 degrees phase
shift in one leg.
IMO, the class of operation is related to how the tubes are biased and
not on wether they are driven in phase or out of phase.
73,
Jon
KE9NA
--------------------------------------------------------------------------
Jon Ogden
jono@enteract.com
www.qsl.net/ke9na
"A life lived in fear is a life half lived."
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