Yesterday, I’ve noticed that Z-SAT is transmitting 9k6 GMSK instead of its regular CW beacons.
I have not been able to decode anything yet.
Either the signal is not strong enough or there are just empty transmissions.
Could somebody schedule observations in 9k6 instead of CW?
Hello, I scheduled an observation of Z-SAT this evening and acquired this. I can confirm that the satellite is not transmitting the usual CW beacon.
If other recent observation don’t include CW singals from Z-Sat, feel free to mark the transmitter as inactive in a suggestion in DB. More details how to do that you can find them in Transmitter Suggestions - SatNOGS Wiki
After a week’s poking at the signal and getting stuck I notified @EA4GPZ and gave a strong recording to him. He worked out the mystery and made a blog post and X-link
I’ve tried to add a comment to the post but obviously it didn’t work.
For those of you who like to try the BBS, this would be the comment:
Regarding the BBS, Z-Sat and the Chubusats are pretty identical.
“The usage of the BBS is (…) same as ChubuSat-2 except frequencies”According to the archived Chubusat-2 website the downlink of the BBS is at 9k6 GMSK.
Since telemetry is also at 9k6 GMSK and could be decoded with a G3RUH modem according to JA5BLZ, it’s likely that BBS downlink also uses G3RUH.However, the BBS doesn’t make use of AX.25, but of a different format.
I’ve tried to uplink a message list request and to send a message using the described format in the hope that the 9k6 signal was just an empty transmission from the BBS, but without any response or change in the signal so far.
Be aware that the uplink is at 1k2 FSK not AFSK. I don’t know if it’s also G3RUH scrambled or not.
