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AMSAT-bulletin om SSETI

Hr kommer den officiella bulletinen om SSETI Express:

The SSETI Express satellite launched at 06:52 UTC on Thursday, 27 October 2005 on board a Kosmos 3M launcher. One hundred and three minutes later, exactly on schedule, the first signals were heard form the groundstation in Aalborg, and two-way communication was established. In addition to several successful communication sessions with SSETI Express, two of the Cubesat passengers, UWE-1 and Xi-V, have been heard by their groundstations.

An official release from ESA stated, 22:20 CEST SSETI Express went into a safe mode due to an undervoltage caused by battery charging problems. The operations team is working actively to resume nominal operations of the satellite and is receiving tremendous help in the process from the amateur radio community. At the time of the anomaly many mission milestones had already successfully
been met.

Graham, UA/G3VZV reports, that it seems that no reliable reports of any signals have been received and the teams are reviewing all the telemetry already received to fully understand what is happening on board.Initial review suggests that there is a significant chance that the power supply problem may correct itself. Graham also advises that the command station in Aalborg is planning to try to try a blind command of the satellite into S band on mode – maybe on a Sunday am pass at 10:30 UTC.

As the statement above makes clear, ESA and the SSETI Association greatly value the input that amateur operators are providing and would ask amateurs around the world to continue to check for signals on 437.250MHz at the appropriate pass times. These signals may be short bursts of 9k6 data every 18 secs or bursts of pulse telemetry every 30 secs. Please understand that the pulse beacon decoder can produce spurious results on plain noise if over driven!

Anyone hearing anything that matches the above detail is requested to please email details to missioncontrol@sseti.org The type of the first transmissions will depend on the state of the battery. In Nominal mode – a sub 1 second burst of AX25 9k6 FSK telemetry every 18 seconds on the downlink frequency of 437.250 MHz.

In Recovery or Safe mode – simple on/off telemetry comprising 16 x 100 msec carrier pulses. This telemetry is repeated every 30 seconds in Safe Mode and every 2 minutes when in Recovery Mode. The satellite will transmit at a power of 3 watts.

A daily report of the launch campaign is being maintained at
http://sseti.gte.tuwien.ac.at/express/mop/index.php?uri=news.html This mission operations site is completely up-to-date regarding Kepler TLEs and other LEOP Launch and Early Operations Phase details.

The SERACC software, needed to decode and submit the received data to the SSETI database, together with some audio files containing recorded 9k6 signals to experiment with is also now available The ESA website about SSETI Express is at:
http://www.esa.int/SPECIALS/sseti_express/SEMARJ7X9DE_0.html

The latest version of the SSETI Express handbook can be downloaded free of charge from the AMSAT-UK website at:
http://www.uk.amsat.org/

Klla: AMSAT

By SM0TGU

Webmaster and member of the AMSAT-SM steering group.

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