Garry, you are presuming that all radios generate AFSK internally. Perhaps
your radio does it that way. One of mine (FT-1000D) does, but another I
have (IC-756PRO) does not.
All the KAM can do is furnish the "FSK" logic signal to the radio. What
happens then depends on the radio.
My FT-1000D internal AFSK method appears to work adequately, but I suspect
that it _probably_ has a slightly dirtier signal (low level junk near the
M/S freqs) than my 756PRO.
The weaker signals on the band in last weekend's RTTY contest would have
been much easier to copy if more of the guys nearby them had their (sound
card generated) AFSK actually under control.
Jerry W4UK
At 07:47 10/11/02 +0000, garry@ni6t.com wrote:
>You say your KAM "actually keys true FSK," but that is not correct. The KAM,
>and all other "FSK" sources, provide logic-level outputs that do not
>directly manipulate the frequency generator in your radio, but which select
>dividers in the radio that provide tones to modulate your SSB transmitter
>downstream from your microphone preamps. IOW, you are merely generating AFSK
>with logic levels, and most certainly do not eliminate your audio stages.
>What it does free you from is the necessity to worry about microphone gain
>and the status of your compressor.
>
>73,
>
>Garry, NI6T
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