UoSat 1, 2 (UO 9, 11 / UoSAT-OSCAR 9, 11)

UoSat 2 [SSTL]

UoSAT-1 (University of Surrey Satellite) was launched on a Delta-2310 from Vandenberg AFB, as a secondary payload to the SME. It was placed into a 560 km 3am-3pm sun-synchronous orbit, and was to investigate and demonstrate the feasibility of the design, construction and launch of a scientific satellite at low cost. The satellite program was completed within a 30 month time-scale, a within a budget of 250k pounds. It was designed, built, and operated by the University of Surrey team. UoSAT-1 signals were heard, decoded and analysed by thousands of radio amateurs, schools, colleges, and universities around the world.

In April 1982, after seven months in orbit, the satellite uplink was inadvertently blocked by the downlink, preventing commands from being received. This situation lasted until September, but with the assistance of the Stanford Research Institute in the US, this situation was solved. The predicted orbital lifetime was 3.5 years, but the satellite was only to decay more than 8 years later on the 13th October 1989, whilst still operational.

The satellite structure comprises a central truss which carries 16 electronic modules.

Payloads:

• Electromagnetic and Propagation Studies Experiment
  A collection of experiments were designed to study the near-Earth electromagnetic environment and its relationship to radio wave propagation in HF to microwave bands.
• Magnetometer experiment
  A three axis flux-gate magnetometer with +-2nT resolution is included to provide precise attitude determination.
• Particle radiation experiment
  Two radiation detectors are included, the first for electrons with energies greater than 20 kEv, and the second for electrons with energies greater than 40 kEv. Each provided real-time data on solar activity and auroral events. The correlation with radio wave propagation was also to be investigated.
• HF beacons
  A set of four phase-related HF beacons at 7 ,14, 21 and 28 MHz provide a tool for HF propagation studies through te ionosphere.
• VHF, UHF and microwave beacons
  Beacons at 146, 435, 2.4 GHz, and 10.5 GHz support studies into the effects of geomagnetic and solar disturbances, local weather conditions and other phenomena on radio propagation.

UoSat 2 was similar.