Observation 1006461: Taurus-1 (99902)

Regarding Observation 1006461

IQ raw spectrum for this possible Taurus-1 at:

Or this should work now:

Still working on getting re-acquainted with s3 permissions etc - let me know if this works for anyone:

$ aws s3 cp s3://satnogs-iq-cwv/1006461.raw 1006461.raw

Packets decode using gr-satellites / lilacsat1.py with the message debug block enabled, using raw iq with gqrx in USB at 9.6k offset below, udp to ./lilacsat1.py
(tip of the hat to k4kdr tweets for a clue https://twitter.com/scott23192/status/1172553961984974848)


another one s3://satnogs-iq-cwv/1006462.raw

Might be misleading frequency for Voice - I observed nothing on 436.760MHz last night https://network.satnogs.org/observations/1020725/ - turns out the activity was around 435.834

wanting to record iq spectrum to decode audio. Found this note from: https://amsat-uk.org/2019/09/13/taurus-1-with-codec-2-launched/
" (no response on 436.760 MHz when transmitting on 145.820 MHz)” Note: this was sent before it was realized Codec2 voice and the telemetry were on the same frequency."


Was able to demod some voice fragements from observation

but not much intelligible, from the pretty weak signal, sample: http://swigerco.com/taurus_1026508_fragments.wav

raw iq is at http://satnogs-iq-cwv.s3-website-us-east-1.amazonaws.com/ or direct if listing script not working:

converted from short to float as usual with:
$ sox -es -b16 -r48k 1026508.raw -ef 1026508_fc.raw

Then used this version grc script derived from k4kdr’s: http://swigerco.com/demod_taurus-1-satnogs.grc
which was changed to use file input instead of udp, removed Plan13 since you already doppler correct, and fixed a file sink name to something generic.

But wait, it gets even uglier - the gr-lilacsat scripts were created with an older version of python ‘Construct’ 2.8.21 or earlier, and gr-satellites now uses version 2.9 - SO I check out an older version of gr-satellites that works with 2.8.21
$ sudo pip install construct=2.8.21
$ git checkout 40319495558fafc910253b68b616235d72b6304c
rebuild and then above script works, and outputs the audio sample above.

Now just need a better signal :wink:

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