Conan Ford wrote:


Here's an idea: use a digital frequency counter circuit, like the S-350 has,
but have a circuit that reads the value, and if it drifts without the user
touching the knob (you could tell by capacitance on the knob) have it correct
itself. You'd have to have a small motor drive to turn the mechanism.
Perhaps you could then have the lower-noise sound of an analog radio with the
non-drifting benefits of digitally tuned radios. Or, have an entirely analog
radio, except have a digital circuit to activate a motor and turn a variable
capacitor inside the radio.

Seems it would be easier to just use a Oak Hill DDR box, or whatever
with the older rig. You would have to have one heck of a slow bandspread
to be able to accurately have a motor tune the radio. Would be easy to
overshoot, etc..Their box can be used on many types of radios..You can
have analog radios that don't drift enough to notice. My Drake R4
"1965-serial #0058" is all tubes, and totally analog, and it doesn't
drift enough to worry about in the real world. The only real plus to
adding the DDR to it, would be the readout. The old drake 4 line was
pretty stable for it's time, and had the advantage of having the same
drift rate, etc, no matter what the freq. It's still quite usable even
today, even on picky SSB, or even digi stuff. Same as the Collins, that
used the similar circuit. Actually, I think Drake more copied Collins,
than the other way around. Drake used to work at Collins the way I hear
it...Then started his own company. My drake T4XB transmitter VFO is even
more stable than the tube version in the R4. It uses solid state parts
for the vfo, instead of the 6AU6 in the R4. When I run the pair, I tend
to use the xmtr vfo...MK

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