PSAT seems to be returning to good health. We will keep the digipeater off, but will now announce it is safe to resume PSK31 experiments.
Remember, when we ran out of power, great progress had been made with Andy's pre-compensating PSK31 uplink software (below). Here also are the latest elements for PSAT:
PSAT 1 90720U 15234.36512451 +.00008395 +00000-0 +21488-3 0 0099 2 90720 054.9897 293.1329 0244566 052.6872 309.6216 15.1526532401420
When PSAT-1 is using the PSAT-1 callsign, that means the digipeater is off. But as of now, PSK31 experimentation is authorized. 28.120 PSK31 uplink and 435.350 FM downlink.
Bob, WB4aPR
-----Original Message----- From: AMSAT-BB [mailto:amsat-bb-bounces@amsat.org] On Behalf Of aflowers@frontiernet.net Sent: Wednesday, July 15, 2015 6:41 PM To: amsat-bb@amsat.org Subject: [amsat-bb] PSAT PSK31 experimental software
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 _______________________________________________ Sent via AMSAT-BB@amsat.org. AMSAT-NA makes this open forum available to all interested persons worldwide without requiring membership. Opinions expressed are solely those of the author, and do not reflect the official views of AMSAT-NA. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://www.amsat.org/mailman/listinfo/amsat-bb