UNISAT-6 first video from orbit and its first three months of operations

UNISAT-6 has travelled over 73 million kilometers since its launch, completing over 1656 orbits. During this period the satellite has transmitted more than 16 megabytes of recorded telemetry and 518 pictures. Even if these numbers might not be very spectacular in today’s standards, it is a great achievement for a satellite communicating in UHF with a bandwidth of 9600bps.

From those 518 pictures, around 450 were made in very low resolution in order to get a video of the satellite while rotating, those videos have been already downloaded and have been posted in our Youtube channel in order to share them with you. But we did not want to make it too easy for you! Most of these videos are yet secret and the URLs are broadcasted by UNISAT-6 text beacon. This is our personal way to thank the radio amateurs community, that has been sending us telemetry of the satellite every day. If you want to be the first one in watching any of these videos, you will have to point your antennas to our satellite and listen up carefully! Otherwise you will have to wait that we make them public some days after the broadcast of the satellite.


UNISAT-6 video over Europe recorded on the 27th of July 2014 starting at around 9:22 UTC.
The camera that we have installed on Unisat-6 is a COTS that was intended to be used only during the first 48 hours of mission, the only modification we made was to change its plastic structure with aluminum. Since it is still working we have made some room in our daily UHF telemetry downloads to get pictures once in a while.

Camera on UNISAT-6

Camera on UNISAT-6

UNISAT-6 is flying with three packets of batteries, two of them non rechargeable that were used for the first month of operations and the release of the cubesats. Now the satellite is relaying completely in the main battery packet and the solar panels, both working well up to this point, the other two backup battery packets are now fully depleted.

If you don’t want to invest much money but you still want to hear UNISAT -6 while it passes over your home, you can just use a small SDR and a 9dB homemade Yagi antenna, or you can even use a low-end handset to listen to it.

Waterfall of reception of UNISAT-6. The signal fades while rotating

Waterfall of reception of UNISAT-6. The signal fades while rotating

During these three busy months we have been getting used to the operations of the satellite from the ground. The satellite passes over our antennas around four to five times a day, with a duration of a little over ten minutes per pass. This makes the operations a big challenge, especially when critical events happen on board and there are very few minutes to decide your ground commands carefully in order to not harm the satellite.

If you have been following us on twitter (@gaussteam), you already know that the satellite has entered in Safe Mode three times over the last three months of operations, all the three events were related to the internal flash memory handling of the satellite. Two of the events were triggered due to an operation error while handling it, the other event was a latch up generated while passing over the South Atlantic Anomaly that was cleared after power cycling the satellite for around 100ms. All these events were correctly handled by the onboard systems, halting non critical operations and calling home for diagnostics and help.

We have also completed the works on the ground station, we have now ended two weeks of full automatic operations without the need of operators. We now have a weekly meeting to decide the operations of the satellite and within a few minutes all the commands for the following week can be loaded on the ground station than then properly handles the commanding and the download of telemetry or picture data. If any anomalies occur, the ground would always send a warning email to the operators on call and halt the operations waiting for human control.

UNISAT-6 automatic ground station software

UNISAT-6 automatic ground station software

We are now working on ground with the engineering model to change the radio reception from 9600 to 1200 bauds in order to make easier the uploading of commands or the future “digipeater” onboard the satellite.

Stay tuned with UNISAT-6, await for a picture gallery and more videos that are coming in its beacon!

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