wrote:
I guess back to the drawing board. What I was thinking was to use a
genny as VFO to
inject a carrier into a buffer amp driving a CW amplifier.

What is a "genny?"

'Genny' means "regenerative receiver circuit", typically a direct
conversion regenerative mixer/oscillator followed by an audio amplifer.
Sometimes preceded by an RF amplifier to help prevent the carrier from
radiating back into the antenna.

Where's the PWM coming from? You could have a stock sine wave oscillator
driving a PWM modulator built as a relaxation oscillator, but somewhere you
need the modulation.

(Of course, doing this in the analogue domain kills most of the advantage,
but it still might e worth trying).

There's plenty of them out there but only recently did I see a few that
used tubes wired in space charge mode for 12V operation. One of the
designs slapped on a crystal oscillator as QRP transmitter to create a
full transciever, but why not simply use the regenerative oscillator as
a VFO into the transmitter?

Because the regenerative oscillator isn't exactly stable, to begin with.
Also, if you're running a switching output stage, you need a PWM signal
whose duty cycle in some way corresponds with the waveform you want to
produce, and that takes a bit more than just a simple free-running oscillator
(which is what a regenerative amplifier is if you crank that regen control
up too much).
--scott
--
"C'est un Nagra. C'est suisse, et tres, tres precis."