"Stefan Wolfe" ) writes:
"Stefan Wolfe" wrote in message
...
You use it to transmit from
your serial port directly to the AM commercial band (10000 Khs) and the
other side listens on a commerical AM radio.
http://sci-toys.com/scitoys/scitoys/...ansmitter.html
Whoops, typo....S/B 1000Khz.


And wouldn't it be A2? Or have they tossed out that designation?

A2 was/is an audio tone into an AM transmitter.

It's what's used for the "code" function on all those old "no license
required" 100mW 27MHz walkie talkies with the code keys. It has
the advantage that you don't need a BFO at the receiver end.

ANd of course, there was that period in the US when the 2M phone
privilege went away for the Novice class license, but A2 continued
to be allowed, presumably because all the cheap AM transceivers had
no means of sending CW.

Michael VE2BVW