Why no Direct serial port FSK?

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M0FMT's picture
Last seen: 1 year 1 day ago
Joined: 2009/11/12 - 09:35
Why no Direct serial port FSK?

The WSPR 4tone FSK has been cracked so that the wspr data can be directly modulated. This facility does not come as part of the software package. Direct modulation produces a clean signal an SSB TRX using an audio tone is transmitting a 3kHz bandwidth of noise along with the desired audio tones.
Question is why is no serial port direct keying option provided for all these weak signal software packages FT8 for instance? It makes more sense than the audio tones.