[amsat-bb] Need help decoding EO-79 packets.

Jeff A. Boyd the2belo at msd.biglobe.ne.jp
Thu Apr 21 15:18:02 UTC 2016

I have been trying for weeks to set up a system to decode telemetry packets from
EO-79 (QB50P1) without success. As I am new at dealing with data from satellites
that is not already handled by a dedicated program such as FUNCube Dashboard,
which handles Doppler tracking and packet decoding all by itself, I'm still kind
of lost as to how all the required components are supposed to come together.

If I can figure out EO-79, goes my thinking, then I can go on to tackling other
BPSK 1200 baud birds such as the XW-2 constellation. I will list what I'm doing
below; if someone can please give me a sanity check it would be greatly

- Receiver: FUNCube Dongle Pro+, SDR# outputting to a virtual audio cable.
- SATPC32 tracking EO-79, correcting for Doppler, and controlling SDR#.
- AGW Packet Engine set up with "Sound Card" TNC (the other end of the virtual
audio cable), dual port, 1200 baud for each channel.
- AGW Online KISS set up to connect to the Packet Engine. WINSock remote port
- Soundmodem by UZ7HO on the same port 8000 and listening to SDR#, which
is set for USB, 4kHz bandwidth. SATPC32 is keeping the packet traces in the
center of the 4kHz passband, and I can see the traces appearing in the waterfall
in Soundmodem. The modems in Soundmodem (2 channels) are set for BPSK 1200 
baud, and the reticules match up exactly with the traces I can see in the

And Soundmodem refuses to decode a single #$%&ing thing. There is an occasional
"<NON AX.25 FRAME>" that shows up in the list, and Online KISS will show a bunch
of garbage, but this mostly occurs when there is nothing in the waterfall at all.

Several sites have said that I'm to connect something to something else using
virtual serial ports, but none of them have really given me a straight answer as
to where to connect what to what.

What am I doing wrong here? Any advice would be ridiculously appreciated.


J. Boyd, JR2TTS/NI3B
the2belo at msd.biglobe.ne.jp
Twitter: @Minus2_C

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