[Milsurplus] BC-9 again

[Hubert Miller]

re the BC-9 frequency shift again. I wanted to know if anyone had a handle on how much the tube operating point alone would shift the frequency.
I asked on a couple other groups. Wha t i learned is that i had grossly overestimated this effect. In fact one fellow had already done a lot of
experimenting with the single-tube free-running oscillator as a single tube transceiver. He opined that that frequency shift was not that large and
the effect could be useful for the BFO-type offset. It seems the effect is well less than a kHz on the frequencies we are talking about. One fellow
mentioned in a VFO the B+ change at these steps to be about 250-300 Hz. So in the case of the BC-9 mystery, the tube effects are minor, and it's
practically all due to the particular design of the circuit.
As Ken commented, the parts values were empirically arrived at. Absolutely !
-Hue
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