On Mar 30, 2015, at 9:04 PM, John L Merrill wrote:
> Someone might correct me but FSK on this radio is actually keyed AFSK like
> it was in the FT1000 and FT990.
Starting with the FT-1000MP, the 1000-series performed FSK using the DDS chip.
They are true FSK transmitters (with all the honest and goodness, dirty FSK
sidebands :-).
You are correct about the FT1000/D and FT-990. Those generated AFSK by using a
pseudo 3-bit D/A converter (a register with resistor weights) with the clock
frequency keyed by the FSK keying line ("keyed AFSK"), so at least they are
phase continuous.
With the FT-1000MP, "RTTY" selects FSK, while "PKT" selects AFSK.
73
Chen, W7AY
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