To add to what Tom said, Pappenfus recommends the circuit for high gain tubes,
and specifically mentions the 4CX250B and 4CX1000. There is also a caveat
against grid current, but a suggestion that IM3 of -50dB can be obtained. If
you don't have that virtual ground for RF between plate and grid which the
screen supplies, I don't see it working.
I can see how you could do it with triodes: you'd need two of them in series in
a cascode arragement. Why you would ever consider doing so other than a purely
academic exercise is another matter, unless maybe, you wanted to grid modulate
the top one for AM. It would have to be a contender for most useles circuit
idea ever, though.
73
Peter G3RZP
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