[VK2TPM] Built the QRPGuys AFP-FSK Digital Transceiver III kit

[VK2TPM via rec.radio.amateur.moderated Admin]

marxy's musing on technology

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Built the QRPGuys AFP-FSK Digital Transceiver III kit

Posted: 15 May 2022 09:31 PM PDT
http://blog.marxy.org/2022/05/built-qrpguys-afp-fsk-digital.html

A QRP Labs QDX digital transceiver kit is on order but in the mean time I
was looking for information on the technique Hans uses to modulate the
Si5351 from a computer generating FSK modes, such as WSPR. The manual
mentions that the way it works is to measure the frequency of the audio
coming in from the computer and then directly set the Si5351 frequency.
This means there's no mixing and no