[aprssig] Standard 2400 baud AFSK tones?

scott at opentrac.org scott at opentrac.org
Wed Nov 10 20:57:29 EST 2004

What are the standard tones used for 2400 baud AFSK?  I found one reference
that says they should be 1775 and 3250 hz.  Others make references to
TCM3105s overclocked to 7.3728 or 8 MHz, but don't specify the tones
produced.  Based on the standard frequency of 4.433 MHz, I'm assuming those
should be 1996 / 3659 and 2166 / 3970.

I'm attempting to test the OpenTracker at 2400 baud just for kicks, but all
I've got to test with is AGWPE, which doesn't seem to specify the tones used
anywhere.  None of the above have worked, which means that either I've got
the wrong tones, or there's just something else wrong with my modulator.



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