RAX Launch Event

The RAX (Radio Aurora eXplorer) 3U cubesat build by students at the Aerospace Department at the University of Michigan was launched on November 19 (Alaska time). The DTUsat team manned the ground station and listened for beacons as the satellite passed over DTUsat GS at DTU.

Expected orbit: 650 x 650 km, 72°

Launch site: Kodiak Island, Alaska

Expected launch time:

Zulu 01:24 - 02:54 20. November 2010.

Kodiak, Alaska 15:24 - 16:54 19. November 2010.

CPH 02:24 - 03:54 20. November 2010.

With the recent release of NanoSail D - again we have manned the GS and listens for beacons. Results will be posted at the end of this page - scroll down.

More information on the NanoSail D mission may be found here.

In total six satellites (one two-pair) will be launched on the Minotaur-4 HAPS under the STP S26 programe these are:

• FASTSAT HSV 01 170 kg
• O/OREOS (Organism/ORganic Exposure to Orbital Stress) 5,2 kg (3U Cubesat)

  O/OREOS Beacon: 437.305MHz

• Falconsat 5
• RAX (Radio Aurora Explorer) (3U Cubesat)

  RAX Beacon: 437,505 MHz (not CW, i.e. not suited for audible tracking)

• Nanosail D2 (3U Cubesat) 0,5 sec beacon every 5 sec. Mission runs on primary batteries hence mission duration is short (70-100 days to re-entry).

  Nanosail D beacon: 437.270 MHz

• FASTRAC-A -B Formation satellite, i.e. a satellite pair of 15 kg.

  FASTRAC A Beacon: 437.345 MHz

  FASTRAC B Beacon: 145.825 MHz

From left to right the satellites are: FASTSat HSV, O/OREOS, Nanosail D2, FASTRAC-A -B.

The OZ2DTU GS tracked the RAX satellite during the first pass over Denmark. While our radio clearly received beacons from the satellite the TNC was unable to decode them. On the audio recording first sign of a beacon shows up at approximately 4min and 31 sec into the recording. It seems the audio is clipped, next pass we'll reduce the Line In gain.

Click on image to hear low quality Squelch Break.

During this pass the adjusted Line In amplification gaves us a much better signal.

A better squelch break recording. In total 3 breaks are in this recoding, approx. 20 sec apart. Recording starts at 07:06:10 Local Time (UTC +1h).

We shifted the tracking of RAX 50 sec ahead, which seemingly gave a better reception. 8 min into the pass we listened for O/Oreos which have a more audible beacon (AFSK modulated). Click images below to hear the results.

RAX rec starts at 08:41:30 (UTC +1h) (1. image). First beacon at 08:41:36 we've shifted 40 sec ahead in track. At 08:41:56 we shifted 60 sec ahead in the track. 08:42:16 we were 40 sec ahead. Second image file starts at 08:42:30 (UTC +1h). First beacon (08:42:36) we're 50 sec ahead staying there for the reminder of the RAX recording. At 08:46:07 (UTC +1h), third image, we heard the first O/Oreos beacon this recording starts at 08:46:00.

The screen dump below shows the succesfull packet decoding from the RAX beacon using the SW provided by the RAX team.

Congrats with your succesfull launch, deployment and packet decoding.

Click image to enlarge

Only backgorund noise reduction every 10 seconds was received by our GS. The signal was to weak to be detected by anything but the human ear. Moving 60 sec back and forth in the pass did not yield any results.