Command Logic Demodulator, Communications Satellite

Communications satellites are composed of a complex array of electronic devices that facilitate the receiving or sending of signals (known as the payload) with ground stations on the Earth, or support the operation of the satellite.

This device, a command logic demodulator, performed the second function. Its role was to ensure that a command (such as turning on a motor to reorient solar arrays) sent by ground operators was valid and correct before it gets executed.

This artifact was a back up and test device for the module that flew on Satcom 1, a communications satellite built by RCA Astro Electronics, launched in 1975, and operated by RCA Americom. Satcom 1, a milestone in communications satellite history, was one of the first satellites used by US broadcast networks (ABC, NBC, and CBS) and cable TV channels (such as TBS and CNN) to distribute their programming over large geographic areas. Since the late 1970s, distribution via satellite has helped to make cable TV a staple of everyday life in the United States and other countries.

Lockheed Martin donated this artifact to the Museum in 1998.