AMSAT is a name for amateur radio satellite organizations world-wide, but in particular the Radio Amateur Satellite Corporation, Silver Spring, Maryland, near Washington DC. AMSAT organizations design, build, arrange launches for, and then operate (command) satellites carrying amateur radio payloads, including the OSCAR series of satellites. Other informally affiliated national organizations exist, such as AMSAT Germany (AMSAT-DL) and AMSAT Japan (JAMSAT).

History

AMSAT-NA was founded in 1969 in Washington DC to continue the efforts begun by Project OSCAR. Its first project was to coordinate the launch of OSCAR 5, constructed by students at the University of Melbourne. Some design modifications were needed and were made by AMSAT members, and the satellite was successfully launched on January 30, 1970 on a NASA Thor Delta launch vehicle.

AMSAT's next launch was AMSAT-OSCAR 6 (AO-6) on October 15, 1972. AO-6 was AMSAT's first long-life satellite, and was built with participants from Australia and West Germany. Command stations in Australia, Canada, Great Britain, Hungary, Morocco, New Zealand, the United States and West Germany controlled the satellite, contributing greatly to its 4½ years of service. Further launches continued to emphasize international cooperation, with AMSAT-OSCAR 7 (AO-7) launching with a new transponder developed and built by Karl Meinzer and AMSAT Germany (AMSAT-DL). AMSAT Japan (JAMSAT) contributed a transponder to AMSAT-OSCAR 8 (AO-8).

In order to launch its satellites, AMSAT has worked with space agencies and commercial launch contractors to develop new ways to take advantage of unused areas of launch vehicles. In return, AMSAT sometimes can negotiate a reduction or waiver of launch costs. One of the most significant is the Ariane Structure for Auxiliary Payloads (ASAP), developed and manufactured in partnership with the European Space Agency in 1990 for use on its Ariane IV launch vehicle. AMSAT was again able to take advantage of unused space with the launch of AMSAT-OSCAR 40 (AO-40), occupying unused space on an Ariane V.

Satellite Phases

The AMSAT Phase system describes an amateur satellite based upon its capabilities or mode of operation and roughly parallel the development of amateur satellites.

• Phase 1: No solar cells (battery-powered only), short-lived, technology test-bed. Must be able to orbit to be classified as a satellite.
• Phase 2: Long life using solar cells, communications capabilities, Low Earth Orbit.
• Phase 3: Long life, more powerful communications, telemetry and command systems. Highly elliptical orbit, usually a Molniya orbit; usually the initial orbit is a Geostationary transfer orbit, onboard propulsion systems boosting it to its final orbit. Because of the highly elliptical orbit, the satellite remains over an area for long periods of time, allowing amateurs longer contacts through the satellite..
• Phase 4: Amateur satellite in Geostationary orbit. Phase 4 amateur satellites have been designed, but not built, though they have received favorable attention.
• Phase 5: Spacecraft capable of lunar or planetary missions.

Satellite Mode

Mode descriptions for currently operational satellites.

Mode A: Uplink 2M   Linear  Downlink 10M
Mode B: Uplink 70CM Reverse Downlink 2M
Mode J: Uplink 2M   Reverse Downlink 70CM
Mode K: Uplink 15M  Linear  Downlink 10M
Mode T: Uplink 15M  Linear  Downlink 2M

Active Amateur Satellites

For the latest list of active satellites and their operational frequencies, please consult the AMSAT's Weekly Satellite Reports that I post in the Amateur Radio RAC/ARRL bulletins forum.

Scanner and Radio Communications Ring Owner: David Bate Site: ScannerDesk and VA3DBJ