New Amateur Radio Satellite Project

AMSAT-UK Chairman Martin Sweeting, G3YJO, has announced that an Amateur Radio transponder will be part of the European Space Agency’s (ESA) Student Space Exploration and Technology Initiative (SSETI) “Express” satellite. Onboard will be a 2.4 GHz transmitter and a 437 MHz receiver. The pair will be turned into an amateur FM voice transponder after the transmitter serves initial telemetry duty.

“These frequencies will enable the many amateurs who already have AMSAT OSCAR 40 equipment to use it in an exciting new way,” Sweeting said. Sweeting told participants at the 2004 AMSAT-UK Colloquium July 30-August 1 that AMSAT-UK has arranged with the ESA to provide–at very short notice–an S band transmitter for the SSETI Express. The 2.4 GHZ transmitter will become the downlink of the single-channel FM U/S transponder. Holger Eckart, DF2FQ, will provide the UHF receiver.

An AMSAT-UK team is developing the 2.4 GHz downlink exciter, switching-mode power supply and control interfaces. A 3 W 2.4 GHz power amplifier–identical to the one flying in the recently launched AO-51 “Echo” spacecraft–already has been completed. The S band antennas consist of three flat-plate patches, engineered and produced by Wroclaw University of Technology in Poland.

The SSETI Express is believed to be the first-ever pan-European student satellite with more than 100 students and their teachers at several European universities working on the project. The 2.4 GHz downlink transmitter will send satellite telemetry and data at 38.4 kb/s before being switched over to voice transponder operation once onboard experiments have been completed.

Spacecraft integration is due to start this month at the ESTEC laboratories in the Netherlands. Plans call for launching the 80 kg spacecraft into a 680 km sun-synchronous orbit next April from Plestek, Russia.