[GreenKeys] Dovetron TU question - keying a transmitter

[Jim Haynes]

I would say from the vintage of the Dovetron that it was most common
to have a send-receive switch separate from everything else that would
turn the transmitter on when you want to transmit.  Certainly true of
earlier stuff.  The AFSK generator would run all the time, so VOX was
not used.  And before that AFSK was not used, but rather the frequency
of the transmitter was shifted by a shifter mod to the VFO.

Some of the more modern radio equipment has an FSK input that is intended
to be controlled by a keyboard DC signal and causes the transmitter to
output FSK when the radio is in the FSK mode.  That's an alternative to
feeding AFSK into a SSB transmitter to generate FSK.  So you have a lot
of choices in how to put together a station.