> Someone sent me this comment when the subject of FSK readouts came up.
> Any thoughts on his plan?
The only problem with using 915/1015 (1 KHz) or any other "low" audio
tones with AFSK is the chance that over driving the microphone input
of the transceiver will produce harmonics that will get transmitted.
The problem is particularly a problem with tones 1 KHz and below since
the 3 KHz harmonic content *will* make it through the IF filter in most
rigs. 3 KHz is right on the "knee" of the response of most modern
rigs.
73,
... Joe, W4TV
On 2/6/2012 3:44 PM, Bill wrote:
> Someone sent me this comment when the subject of FSK readouts came up.
> Any thoughts on his plan?
>
> "You don't have to pick the 2.1 kHz offsets for tones, I use the
> 915/1085 (that is, 1 kHz +/- 85 Hz) to make the spotting arithmetic easy
> (about 1 kHz)."
>
> Bill Marx W2CQ
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