I wasn't there at the very beginning of carrier-type AFSK, but I suspect
it was because it was the simplest, quickest and easiest way. Back
then, with tube-type VFOs, stability was always an issue and trying to
get an exact shift and make it consistent would have been difficult for
a lot of hams. Modulating a carrier with audio tones would have been
simple by comparison, either AM or FM..
Anyone around from those days? Feel free to jump in.
Bill, W7TI
----- Original Message -----
From: "WA9ALS - John" <wa9als@starband.net>
Bill, why was this done? I suppose it was more copyable than voice
under
certain conditions?
Reminds one of using a code practice oscillator on a 2M repeater...
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