These are the 2 10 GHZ "GunnPlexers" that I ordered. The actual size is 1.8" wide by 1.6" tall. On either side of the center metal are 2 antenna elements. 2 for transmit and 2 for receive.
When you look at the metal cover can side, under the ROHS sticker is the frequency tuning screw. The current frequency is 10,525 mhz and the units will mechanically tune down to 10,400 mhz with the tuning screw.
FM modulation is done by varying the +5 vdc to the transmitter oscillator. I am going to use an LM317 regulator that is voltage wobbled by audio. A standard circuit, look up any Solfan GunnPlexer page and use that circuit.
Be aware that the Solfan units use 8 or 9 vdc and these New units want only +5 vdc.
The receiver is a simple mixer circuit, driven by the Transmitter RF. The IF can be anything 1 to 300 mhz and I am making PCBs for 60 mhz Wideband FM, hopefully 200 khz wide.
The Tranmitter is a DRO stabilized oscillator and is a great deal better in frequency stability than the old Gunn diodes. With the wide receiver bandwidth, these units will be practically drift free.
With a 19" dish and using these unit as a splash feed, the dish will have some 33 to 36 DBs of gain and just over 6º of antenna beamwidth.