Amateur radio satellites. For over a third of a century a series of OSCAR satellites have been launched in a variety of configurations and by many nations.
The first Oscar Phase I amateur satellite was launched piggyback with Discover 36. A group of enthusiasts in California formed Project OSCAR and persuaded the United States Air Force to replace ballast on the Agena upper stage with the 4.5 kg OSCAR I package. The satellite was box shaped with a single monopole antenna and battery powered. The 140 mW transmitter onboard discharged its batteries after three weeks. 570 Amateurs in 28 countries reported receiving its simple 'HI-HI' morse code signals on the VHF 2 meter band (144.983 MHz) until January 1, 1962. The speed of the HI-HI message was controlled by a temperature sensor inside the spacecraft. OSCAR I re-entered the atmosphere January 31, 1962 after 312 revolutions. Additional Details: Oscar 1.
OSCAR II was launched piggyback with a United States Air Force satellite. OSCAR II was very similar to OSCAR I. Differences included (1) changing the surface thermal coatings to achieve a cooler internal spacecraft environment, (2) modifying the sensing system so the satellite temperature could be measured accurately as the batteries decayed, and (3) lowering the transmitter power output to 100 mW to extend the life of the onboard battery. OSCAR II lasted 18 days ceasing operation on June 20, 1962 and re-entered June 21, 1962.
OSCAR III was launched piggyback with seven United States Air Force satellites. Weight 16.3 kg. It was the first amateur satellite to operate from solar power and relay signals from Earth. OSCAR III was the first true amateur satellite relaying voice contacts in the VHF 2 meter band through a 1 W 50 kHz wide linear transponder (146 MHz uplink and 144 MHz downlink). OSCAR III's transponder lasted 18 days. More than 1000 amateurs in 22 countries communicated through the linear transponder. The two beacon transmitters continued operating for several months.
Note: Designed, built, and tested, a predecssor, OSCAR* was never launched. Similar in design to OSCAR I and II, OSCAR* contained a 250 mW beacon with phase-coherent keying. OSCAR* was never launched as the workers decided to focus their efforts on the first relay satellite -- OSCAR III.
OSCAR IV was launched piggyback with three United States Air Force satellites. The launch vehicle had a partial failure and placed the spacecraft in a low orbit preventing widespread amateur use. Orbit 29120 x 168 km. Inclination 26.8 degrees. Period 587.5 minutes. Weight 18.1 kg. Four monopole antennas. OSCAR IV was built by the TRW Radio Club of Redondo Beach, California. It had a 3 Watt 10 kHz wide linear transponder (144 MHz uplink and 432 MHz downlink). In operation until March 16, 1966. Re-entry April 12, 1976. Total operation 85 days. OSCAR IV provided the first US-Soviet amateur link.
Australis-OSCAR 5 was launched piggyback with ITOS-1 (TIROS-M weather satellite. Weight 17.7 kg (9 kg of which was battery mass). Box shaped 304 x 431 x 152 mm. 2 meter monopole and 10 meter dipole antennas. It was the first amateur satellite to be remotely controlled. Built by students at The University of Melbourne, Melbourne, Victoria, Australia. Battery powered, Australis-OSCAR 5 transmitted telemetry on both 2 meter (144.050 MHz at 50 mW) and 10 meter (29.450 MHz at 250 mW) bands that operated for 23 and 46 days respectively. Passive magnetic attitude stabilization was performed by carrying two bar magnets to align with the Earth's magnetic field in order to provide a favorable antenna footprint. The University of Melbourne compiled tracking reports from hundreds of stations in 27 countries.
AMSAT-OSCAR 6 was launched piggyback with ITOS-D (NOAA 2). AO-6 was the first phase 2 satellite (Phase II-A). Weight 16 kg. Box shaped 430 x 300 x 150 mm. Quarter-wave monopole antennas (144 and 435 MHz) and half-wave dipole antenna (29 MHz). Firsts: complex control system using discrete logic; satellite-to-satellite relay communication via AO-7; demonstrated doppler-location of ground station for search and rescue; demonstrated low-cost medical data relay from remote locations. Equipped with solar panels powering NiCd batteries, AO-6 provided 24 V at 3.5 W power to three transponders. It carried a Mode A transponder (100 kHz wide at 1 W) and provided store-and-forward morse and teletype messages (named Codestore) for later transmission. AO-6 lasted 4.5 years until a battery failure ceased operation on June 21, 1977. Subsystems were built in the United States, Australia, and Germany.
AMSAT-OSCAR 7 was launched piggyback with ITOS-G (NOAA 4) and the Spanish INTASAT. The second phase 2 satellite (Phase II-B). Weight 28.6 kg. Octahedrally shaped 360 mm high and 424 mm in diameter. Circularly polarized canted turnstile VHF/UHF antenna system and HF dipole. Firsts: Satellite-to-satellite relay communication via AO-6; Early demonstrations of low-budget medical data relay and doppler location of ground transmitters for search-and-rescue operations were done using this satellite. AO-7 was operational for 6.5 years until a battery failure ceased operation in mid 1981. Additional Details: Oscar 7.
AMSAT-OSCAR 8 was launched piggyback with LandSat 3 (ERTS 3) and PIX. The third phase 2 satellite (Phase II-D). Weight 27.2 kg. Box shaped, 33 cm high, 38 x 38 cm. Circularly polarized VHF canted turnstile, UHF quarter wave monopole, and HF half-wave dipole antenna system. Another cooperative international effort (United States, Canada, Germany and Japan). AO-8 had a similar store-and-forward service as AO-7 and carried Mode A (145.850-900 MHz uplink and 29.400-500 MHz downlink) and Mode J (145.900-146.000 MHz uplink and 435.100 MHz downlink (inverted)) linear transponders and telemetry beacons on 435.095 MHz and 29.402 MHz. AO-8's primary mission was for educational applications and amateur communications. It was in operation for six years until the battery failed on June 24, 1983.
The satellite never obtained orbit. Weight 92.2 kg. Mode B (435 MHz uplink and 145 MHz downlink) transponder and 145 MHz beacon. VHF and UHF helix wide beam antenna.
AMSAT Oscar 10, registration no D-R 001. Scientific and communication satellite for the amateur radio service. Frequency plan: Transponder U: 435.1 MHz (uplink), 145.9 MHz (downlink), Bandwidth +/- 75 kHz. Transponder L: 1269.45 MHz (uplink), 436.55 MHz ( downlink), bandwidth +/- 400 kHz. Two beacons adjacent to passband. Launch vehicle Ariane L6. First amateur satellite with onboard propulsion (which did not function entirely correctly, due to collision with launch vehicle after separation - hence the not-quite-Molniya-orbit). Computer control failed December 1986 due to radiation damage to memory. As a result, ground control stations have no control over the spacecraft. However, when the orientation is favourable (with respect to the Earth and Sun), OSCAR 10 continues to provide good Mode B service. If users coorperate, OSCAR 10 may provide many more years of service. Project Management: AMSAT-NA (Jan King, W3GEY) and AMSAT-DL (Karl Meinzer, DJ4ZC). Spacecraft sub-systems: Contributed by groups in Canada, Hungary, Japan, United States and West Germany. Spacecraft: Spin Stabilised with Magnetorquers: Power: 50 W solar array, 2 NiCd batteries. Payload: Transponders/Beacons: Mode B: Type: Linear, inverting, 50W; General Beacon: 145.809 MHz (Carrier); Engineering Beacon: 145.987 MHz; Uplink: 435.030-435.180 MHz; Downlink: 145.975-145.825 MHz. Mode L (no longer operational): Type: Linear, inverting, 50W: Beacons: 436.020, 436.040 MHz; Uplink 1269.450 MHz (800 kHz); Downlink 436.550 MHz.
Japanese Amateur Satellite. JAS-1 (Fuji). Amateur satellite communications. Development of amateur satellite technology. Launch vehicle H-I (two-stage) test flight no. 1. Launch time 2045 GMT. Launching organization NASDA. Fuji-OSCAR 12 was launched piggyback with a Japanese experimental geodetic satellite Ajisai (EGS). Weight 50 kg. 26-sided polyhedron, 40 x 40 x 47 cm. FO-12 was the first Japanese amateur satellite developed by the Japan Amateur Radio League (English version) with system design and integration performed at NEC. FO-12 was taken out of service November 5, 1989 because of battery failure.
AMSAT-OSCAR 13 was launched by the first test flight of the Ariane 4 launcher. Size 600 x 40 x 200 mm. AO-13 was the third in a series of Phase-3 type high-altitude, elliptical orbit amateur communications satellites. It was built by an international team of radio amateurs led by Dr. Karl Meinzer of AMSAT-Germany. It carried four beacon transmitters and four linear transponders. AO-13 also contained a digital communications transponder called RUDAK-1. However attempts to get the experiment operating failed. Operational life span was 8 years. Careful analysis of AO-13's orbit in early 1990 by Victor Kudelka, OE2VKW revealed that resonant perturbations exist which lead the satellite into a negative perigee altitude. The perigee was down to 150 km by August 1996 which drastically increased atmospheric drag on the satellite until it reentered the Earth's atmosphere December 5, 1996.
Spacecraft engaged in research and exploration of the upper atmosphere or outer space (US Cat B).
JAS-1b 'Fuji-2'. Continuation of amateurradio services of JAS-1; extension of amateur radio communications area; advancement of amateur radio technology. Launching organization NASDA. Launch time 0133 UT.
Experimental comsat; prototype of medium altitude satellite to be deployed in a constellation of 32 to 45 satellites in 1997-2001. Also carried amateur radio transponders; also performed geological research. Routine communications, collection and relaying of information in the interests of the Ministry of Geology of the USSR and other branches of the country's national economy, and the development of communications between amateur radio-operators.
Operated by Radio Amateur Club de LeSpace.
ITAMsat was built by AMSAT-ITALY. Its mission was to store and forward amateur radio messages.
UNAMSAT was an AMSAT Microsat class amateur radio satellite built by UNAM, the Autonomous University of Mexico.
Subscale amateur radio model of Sputnik 1. Reentered July 29.