“The first part shows me calling CQ and handling the response. The second part shows how the operator can respond to a someone else’s CQ call.”
The idea of hybrid architecture was first implemented in this form by Bob Larkin in his seminal work with DSP-10 transceiver. The details are in the ARRL book Experimental Methods in RF Design and its accompanying CD. An open secret about the EMRFD is that it is also an excellent introduction to Digital Methods and Bob is a great teacher.
I spent a rainy day in Portland with Bob discussing radio and life and that evening we were joined by Jeff Damm (WA7MLH) for an early dinner. This project was born that evening.