I have a basic prototype up and running with the WSPR transmitter. A photo is attached.
It puts out only 10 milliwatts (much less than that by the time it gets to my antenna) and was heard in several places across the US tonight on 20 meter band well after sunset. I track reception reports using WSPRnet.org. A screen shot of those hearing me is attached.
The furthest was W0PAS in Eastern Ohio. That comes out to 155,590 miles per watt!!! Not bad for a radio the size of a matchbook.
Thanks Gary for helping me test it out.
The GPS receivers came today, so that's my next project. I've learned my programming skills leave a lot to be desired! I programmed up the telemetry module yesterday. It converts NMEA lat/lon to grid square, and encodes the altitude and temperature into the telemetry format.