CAS-5A Observation of potential failure

After oldbug (sorry can’t remember your name on here) asked if CAS-5A died in the Matrix Channel I started looking into it.

I began going back thru observations and found when it last had a signal at all, and then continued further back till I found one with data which also appeared to have an anomaly in it.

The following three observation contain this anomaly.
These are the GMSK
This is a Voice / the Linear Transponder

Then all observations after wards just have this single carrier that slowly get weaker over time.

This observation is 5 hours after the anomaly occurred.

This observation is 11 hours after the anomaly.

This observation is about 15 hours after the anomaly.

This observation is about 17 hours after the anomaly.

This observation from about 22 hours after the anomaly shows the voice repeater still working.

This observation is about 24 hours after the anomaly.
Data - SatNOGS Network - Observation 7383603
Voice - SatNOGS Network - Observation 7383297

This observation is about 1 day 1 hour after the anomaly.

This observation is about 1day 2 hour after the anomaly. This is the last observation I can find with any sort of signal from the satellite on its GMSK Transmitter. (No one is scheduling the CW one it seems)

This observation is the next one and has no signals. This was 1 day 6 hours after the anomaly.

This is an observation about 1 day 10 hours after the anomaly, on one of the stations that witnessed the anomaly.

After this there appears to be no other activity on either the Linear Transponder or the GMSK data. Between the Voice observation 24hr after the anomaly and when the satellite fell silent there were only GMSK observations so it is unclear if the transponder continued operating until they both when silent.

It appears to me that the satellite may have somehow locked up and drained its batteries.


look at here:


Yep, already did that’s how I found that observations when the anomaly (Which I now know is caused sometimes when someone tries to access one of the saved images.) occurred. Link for reference

I found that a previous lockup happened on the 3rd (according to some people on twitter.)
SatNOGS Network - Observation 7364643 shows it to do the same thing.

This lockup only lasted 48hrs due to a watchdog timer.

There is no observation between the lockup on the 3rd and the lockup on the 6th that is not just the locked up carrier.

This is the last observation before the observation that shows the lockup that started on the 6th, that looks to have made the satellite fall silent.

Many thanks for all the effort finding all the relevant observations.

I would like to add that the same anomaly also occured 3 days before and lasted at least 18 hours or more (i can’t tell more precisely due to 5 hours gap between the observations).

GMSK Transmitter suddenly fell silent:
2023-04-03 13:44:33

Anomaly visible, only an unmodulated carrier signal:
2023-04-03 15:13:33

Anomaly still present:
2023-04-04 08:20:49

GMSK Transmitter works again:
2023-04-04 13:28:23

System voltages were normal before and after that time:

No idea what happend…

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Seems CAS-5A is still giving us the silent treatment.

Also we do know what the anomaly was, it seems the CAS-5A has a history of sometimes locking up when commanded to downlink an image instead of properly downlinking it. The last times this occurred it re-set itself after its watch dog times elapsed. This time it seems to not be the case.