First-Generation RCA Direct Broadcast Satellites

In October 1982, the Satellite Television Corporation (STC), a subsidiary of the Communications Satellite Corporation (Comsat), contracted with RCA Astro-Electronics to design, develop, and manufacture the first direct broadcast satellite for use in the United States. The contract is for two spacecraft with an early 1986 launch from either Kourou, Guiana, or Kennedy Space Center, Florida. The program is on schedule with all designs finalized, component qualification virtually complete, and the first spacecraft undergoing integration. Although the system will be implemented in phases, some recent design changes will permit the two collocated satellites to deliver six DBS channels to the entire conterminous United States (CONUS), three channels per satellite. Orbital location will be 110° W longitude, which is one of the eight orbit locations specified for the United States at the Regional Area Radio Conference (RARC) in 1983. Each channel is designed to generate 220 W of RF power in the 12.2-12.7 GHz band at the beginning of life; an allowance is made for TWTA efficiency degradation with life to provide 200 W of RF power at the end of life. The three channels per spacecraft are provided whenever the spacecraft is illuminated by the sun, with no requirement for eclipse operation. Each spacecraft has the capability to transmit in either of two different coverage configurations: it can provide coverage to CONUS or to half-CONUS at an increase in e.i.r.p. of approximately 3 dB. This provides additional margin should STC need the higher e.i.r.p. in the future or provides for a flexible time-zone coverage of the United States.