Sedsat

Students for the Exploration and Development of Space Satellite, also called SO-33

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General

Designation	25509 / 98061B
Launch date	24 Oct 1998
Country of origin	United States
Mission	Telecommunications
Perigee/Apogee	574/ 1078 km
Inclination	31.5°
Period	101 min
Launch vehicle	Delta 2 #261

Built by students at the University of Alabama's Huntsville campus.

Power problems started on 27 Oct 1998. Those were later solved but it was found the 2 receivers were not functional.

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End of life

Out of service	since 27 Oct 1998
Cause	numerous problems made the satellite mostly unusable
Decay

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External resources

sat-index articles

Technical data

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Specifications

Prime contractor	seds
Platform
Mass at launch	38 kg
Mass in orbit
Dimension
Solar array
Stabilization
DC power
Design lifetime

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Mode A transponder

Uplink

145.915 to 145.975 MHz (2 Meter band) Modulation: SSB, CW, FM, AM

Downlink 29.350 to 29.420 Mhz (10 Meter Band)
Modulation: SSB, CW, FM, AM AFSK 300 bps
Hf Packet Compatible telemetry downlink

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Mode L transponder

Uplink 1268.175 to 1268.250 MHz (23cm band)
Modulation: FSK digital data at 9.6, 19.2, 38.4 and 56 kbit/sec
Downlink 437.850 to 438.000 MHz (70 cm band)
Modulation: FSK digital data at 9.6, 19.2, 38.4 and 56 kbit/sec
Data Rate: 300 bits/sec AFSK packet data 9600 bits/sec or 57,600 bits/sec
RF output per transponder will be 3 watts average and 15 watts max

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