Communications

PHASE 3B (AO-10)

Amateur Radio Satellite (Elliptical Orbit) · AMSAT

AMSAT-OSCAR 10 / Phase 3B (AO-10), launched in 1983 into a highly elliptical orbit designed to give amateur radio operators hours of continuous contact rather than the brief passes typical of low-orbit satellites. A failed upper stage left it in a lower, more decayed orbit than planned, and an onboard computer failure in 1986 forced operators to control it using only manual commands for years — remarkably, hams kept it useful anyway, and weak signals from it were still being detected decades later.