Many years ago when I was a teenager I remember a guy that was
building a push-pull grounded grid amplifier using 8 *811As. I never
got to see if he finished it or not. The only info I have found so far
is little more than an acknowledgment that such a circuit exist. Any
further information would be appreciated.

Jimmie

On Sat, 29 May 2010 14:36:00 -0700, JIMMIE wrote:

Many years ago when I was a teenager I remember a guy that was building
a push-pull grounded grid amplifier using 8 *811As. I never got to see
if he finished it or not. The only info I have found so far is little
more than an acknowledgment that such a circuit exist. Any further
information would be appreciated.

Jimmie

Though I may be wrong (I often am) a Grounded grid push-pull is not
possible. But I would suggest downloading the manual for the Ameritron
AL-811H amp. It only uses 4 of the tubes but adding another 4 would be
quite simple based on repetition.

Pete wrote:
On Sat, 29 May 2010 14:36:00 -0700, JIMMIE wrote:

Many years ago when I was a teenager I remember a guy that was building
a push-pull grounded grid amplifier /snip/
Jimmie

Though I may be wrong (I often am) a Grounded grid push-pull is not
possible. /snip/

I know where you are coming from. If both tubes of a push pull long tail
pair have grounded grids, it would be awkward to insert the signal.
But if the push pull setup consists of cascode tubes each side, then a
regular grid could inject the signal to modulate the grounded grid tube
cathode current in cascode, to reflect on the other leg.

Brian W