The Molniya-3 group of four satellites was used to create the Orbita communications system for northern regions of the Soviet Union. The land segment used a 12 m diameter parabolic antenna, pointed automatically at the satellite using autonomous electromechanical equipment. Although primarily for civilian applications, later versions were part of the Soviet YeSSS Unified Satellite Communications System. Trials of this version began in the 1980's, with the system being accepted by the military in 1983-1985.