Pete KE9OA wrote:
I think that you can order the crystals from such companies as International
Crystal, but the synthesizer will provide a good solution. I am thinking of
using the DDS as the reference portion of a hybrid design, using a PLL to
clean up the artifacts from the DDS output.
Essentially, the DDS will tune in 500kHz steps, with an I.F. offset that can
be user programmed for the R4 and the SPR-4.
I am tossing back and forth between using an LCD or a 3 digit LED readout.

Pete,

Do you know about this (below) homebrew FS4 design?

http://www.geocities.com/hagtronics/r4.html