Kendal Goodson wrote:

Thanks Grumpy. I'll check supply voltage next. It's not a thermal
problem. The output is nice and stable until key down when it pulls.
It's also frequency stable during keydown, just on a different
frequency. The oscillator isn't keyed, so I don't think it's an
oscillator startup issue.

73,
Kenn

I'm missing something. You said that the 'driver' etc were disconnected
and the osc is not being keyed.

So what is actually being keyed?

-Bill