OSCAR 4

Project OSCAR

Project OSCAR Inc. was started in 1960 by members of the TRW Radio Club of Redondo Beach, California as well as persons associated with Foothill College to investigate the possibility of putting an amateur satellite in orbit. Project OSCAR was responsible for the construction of the first Amateur Radio Satellites: OSCAR 1, launched from Vandenberg AFB in California on 12 December 1961, which transmitted a “HI” greeting in Morse Code for three weeks, OSCAR 2, and OSCAR 3.

Spacecraft

OSCAR 4 massed 15 kg and was a regular tetrahedron with edges 48 cm long. It had four independent monopole antennae and contained a tracking beacon transmitter and a communications repeater. It was powered by a solar cell array and batteries. The satellite marked the first attempt for a High Earth Orbit (HEO) or GeoStationary Earth Orbit (GEO) amateur radio satellite, later categorized by AMSAT as Phase 3 and Phase 4. Improvements from prior OSCAR satellites included a higher power (3 Watt) 10 kHz wide linear transponder (144 MHz uplink and 432 MHz downlink), due to the higher planned orbit.

Mission

OSCAR 4, along with LES-3, LES-4, and OV2-3, was launched on the third Titan IIIC test flight on 22 December 1965 at 14:00:01 UT from Cape Canaveral LC41 just one second behind schedule. From an initial parking orbit of 194 km, the Titan's Transtage boosted into a transfer orbit pending a final burn to circularize its orbit. However, this final burn, scheduled for T+6:03:04 after liftoff,

The satellite remained in operation for 85 days, until 16 March 1966, and re-entered Earth's atmosphere on 12 April 1976.

Legacy

In 1969, AMSAT-NA was founded by radio amateurs working at NASA's Goddard Space Flight Center and the Baltimore-Washington DC region, to continue the efforts begun by Project OSCAR. Its first project was to coordinate the launch of Australis-OSCAR 5, constructed by students at the University of Melbourne.

References

References

1. (2020). "Nanosatellites: Space and Ground Technologies, Operations and Economics". John Wiley & Sons, Ltd..
2. "OSCAR 1". NASA Space Science Data Coordinated Archive.
3. "OSCAR 4". NASA Space Science Data Coordinated Archive.
4. (23 May 1994). "Space Satellites from the World's Garage -- The Story of AMSAT".
5. (27 December 1965). "Titan 3 Transtage Malfunctions, Fails to Achieve Circular Orbit". McGraw Hill Publishing Company.
6. McDowell, Jonathan. "Launch Log". Jonathan's Space Report.
7. (1987). "The Orbiting Vehicle Series of Satellites". British Interplanetary Society.
8. (31 December 1999). "OSCAR 4". Gunter's Space Page.