I put together an experimental program called DopplerPSK to compensate for the Doppler shift on the NO-84 (or NO-83) PSK31 uplink. In essence, its a PSK31 transmitter that is merged with an orbital propagator to cause your transmitted signal to drift exactly opposite to uplink Doppler effect. It does this in a phase-continuous correction so that you don’t get errors due to discontinuous frequency adjustments from controlling a radio in discrete steps.
In the case of PSAT and BricSat, it should cause your signal to stay at constant frequency in the satellite’s uplink receiver, and thus you should get a stable frequency on the FM downlink as well. In turn, this means you should be able to use your favorite PSK31 demodulating software to copy the downlink since the frequency drift should stay well within the AFC tolerance of the software.
Anyway, if there are any adventurous people who are set up to give this a go, I would be interested in seeing if it actually works.
You can find a rough quick-start guide (which contains an explanation of how it works and what you need to get started) and the application package on the rather minimalist page here:
http://www.frontiernet.net/~aflowers/dopplerpsk/dopplerpsk.html
It’s an experiment, so be prepared for disappointment. I am :-)
Andy K0SM/2
…it works great! I am the station at 1000Hz ;-)