Downlink Frequency: 145.827MHz Transmit Power: 250mW Launched: 1 March 1984 NASA Catalog Number: 14781 Altitude: 680km Format: 1200bps FSK telemetry every 30 seconds
UO-11 is apparently running in a default mode controlled by the watchdog timer, 10.3 days ON and 10.4 days off. I have no idea where we are in that schedule but it was transmitting telemetry as it climbed over the horizon tonight.
I had just completed a new cable for the 2m antenna and wrapped it around the antenna rotator. The pre-amp is still down here in the shack, but I connected the FT-736R regardless and listened in. I could clearly hear the signal so I connected a cable from a tap I have wired into the discriminator, plugged it into my sound-card and started recording into Audacity. I would have liked to decode things live, but I was not yet setup and the signal was weak without the pre-amp.
Offline I setup MIXW as a decoder. I expect other versatile digital sound-card packages will work too. The trick is to use RTTY but set the RX Frequency to 1800, the Baud Rate to 1200 and the Shift to 1200. The Character Set is ASCII-7.
I got very few decodes, but I could see partial frames like this:
UOSAT-2 @ ?170506Y072046 00000`010`01020002036FFTVffvvV| 10001110000120003Q30002140005150004Y60007l70006180009190008 2000022100032200002f001240062500m20004Z50052800A29 00B f00 331000232`01320000000735000636000537000028`00B9000A )4000`441000542000$3000744000050`14000247`003$8000x;Np00DE 500805510005"000753006541001+,3Ff6Vv&SF+4 6080E&15FC1620105633341644$026410C620026700016800E6900 D
I hope to remount the pre-amp tomorrow, or at the weekend at the latest. So more to come as I try to decode some of the data.
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