Hi Larry
Yes the only part of the original project that was not open source was the Firmware IC on the SI570 Digital VFO.
There are lots of designs freely available on the internet for Arduino driven DDS/VFO's just make sure that the design you choose can provide sufficient output to drive a Double Balanced Mixer (ADE-1) or add a suitable buffer stage to deive the DBM.
Any further questions please do not hesitate to post a message in the forum.
Regards
Andy de G6LBQ
