WSPR Tracker
Multiple revisions of this tracker have been made. Revision 5 as of the time of writing.
Carries 3 major components:
ATmega328P mcu
Ublox NEO 6M GPS module
SI5351 Clock Generator used as Radio Transmitter
3.3v at 25mA = 83mW transmitter
Transmits WSPR on 20m, 14,097,200Hz.
Half-wave dipole length: 33ft
Custom firmware and PCB layout.
Fabricated at JLC PCB for very thin PCBs.
Headers designed to be removed (cut off) after configuration so lighter for flight.
~5,000 mile max range.
5.5 grams with headers removed, no batteries/solar, no on/off switch.
Here is a mostly populated PCB. A few optional components left off for this particular flight.
Here is a guide showing how to populate the board.
Thanks to very thin PCBs the weight of the tracker can be materially reduced.
Holding the PCB up to the light shows just how thin it is.
Here you can see that removing the headers saves 2.5 grams.