Amateur radio satellites are developed and built by many AMSAT Amateur Radio Satellite Association groups around the word and launched as secondary payloads on commercial launches. Once successfully orbiting the earth, these satellites are given OSCAR orbiting satellite carrying amateur radio designations for example AMSAT OSCAR 7 or AO7.
AO7 was launched on November 15, 1974, celebrating its 50 th anniversary this week, setting the record as the longest operating satellite.
It is often said that, in any system, the batteries are the weakest link. AO7 proved that point when the batteries failed in 1981. AO7 went to sleep for 21 years and woke up in 2002 when, miraculously, the short across the battery disintegrated and the solar panels were able to deliver power directly to the transponders. The satellite now operates when it is in sunlight.
Communicating across space
