Observation 1006461: Taurus-1 (99902)

Regarding Observation 1006461

IQ raw spectrum for this possible Taurus-1 at:
http://swigerco.com/1006461.raw

Or this should work now:
http://satnogs-iq-cwv.s3-website-us-east-1.amazonaws.com/1006461.raw

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
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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)

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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
https://twitter.com/scott23192/status/1174174927710240769

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."

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Was able to demod some voice fragements from observation
https://network.satnogs.org/observations/1026508/

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:
http://satnogs-iq-cwv.s3-website-us-east-1.amazonaws.com/1026508.raw

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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