HAM Radio is not just 'old-fashioned' short wave radio - in some parts it is very close connected to current research and teaching. In this case Amateur-satellite service which is according to ITU Radio Regulations "a radiocommunication service using space stations on earth satellites for the same purposes as those of the amateur service." There are lots of Amateur radio satellites - most famous: The OSCAR series which is an abbreviation for Orbiting Satellite Carrying Amateur Radio.

Our interest tends to miniaturized satellites in academic contexts, especially the CubeSat projects within the TUBSAT series at our university.

TUBSAT

The Chair of Space Technology at TU Berlin develops own satellites with contribution of researchers and students from different fields of studies. Successfully launched satellites are pooled as TUBSAT missions and there are several since 1991. Some of them are carrying amateur radio transceivers and depending of the mission status they are or will be activated for public usage. Usual approach in early stages of the mission is to send some telemetry for reception only. Later on it could be possible to activate also a digipeater.

The specs of current amateur-satellite services:

  • QRG: 435.950 MHz
  • Modulation: 4k8/9k6-GMSK
  • CW beacon: Morse telegraphy via FM subcarrier (F2A)
  • Telemetry: detailed information regarding link and telemetry format here
  • Digipeater: 4k8 only, 10 sec RX interval in idle mode to save energy (TNC#0, pause, TNC#1, pause, ...)

# NORAD Name Call QRG** CW beacon Telemetry Digi Sat bus TX PWR protocol
8 35933 BEESAT DP0BEE disabled broken yes 0.5 W Mobitex
9 39136 BEESAT-2 DP0BEF 435.9485 disabled yes, interval TBD disabled 0.5 W* Mobitex-NX
- 41604 BIROS DP0BIR TBD TBD TBD Mobitex-NX
11 41619 BEESAT-4 DP0BEH disabled yes, over Europe disabled 0.5 W Mobitex-NX
12 42829 TechnoSat DP0TBA disabled TBD TBD*** TUBiX20 1.0 W Mobitex-NX

* BEESAT-2 TNC#0 is weaker
** caused by drift of the TX hardware which can't be corrected
*** after end of mission ~ 08/2018

Additional links: