[ARDF] AM A2A Modulation...

[Matthew Robbins]

Earlier, I wrote:

    ...they recommended using SSB.  That way,
I could key the PTT, and key an audio tone into the mic input.

Just to be clear, the PicCon held the PTT on the whole minute, and
then it put audio tone into the microphone input during the dits and
dahs, and no tone in the spaces.  The little jumper for HTs combined
PTT/mic input was not connected.

I did not account correctly for the SSB offset. Next time I do this,
I'll key the radio on FM (tuned to the fox frequency), and measure it
with a frequency counter, then I'll switch to SSB and the PicCon and
adjust the tuning knob until it's the same as the FM frequency.  I did
try to account for the offset by tuning around and peaking the
received signal with my Ackerly radio with it set to 146.565.  Instead
of 146.565, I was transmitting on 146.562MHz indicated.  Since the
audio tone is 600-800Hz, a 3kHz offset doesn't make sense to me, but
it did peak the whoopee tone.  I was on upper sideband (USB).  That's
what my radio defaulted to---I couldn't remember the "normal" sideband
for 2m.


Matthew
AA9YH
Cincinnati, Ohio