U.S. broadcast satellites

A description is presented of design considerations for possible operational U.S. broadcast TV satellites. Constraints are related to the large area to be covered, the need for low-cost earth stations, and multichannel requirements. The status of high-power tubes is discussed, taking into account 20-watt tubes supplied primarily by European companies, tubes in the range from 100 to 250 watts developed by American and German manufacturers, and 450-watt tubes developed under the sponsorship of the German Space Agency. Attention is also given to developments in the area of high-power solar arrays, the wide-area coverage provided by U.S. broadcast satellites, aspects of multiple spot beam U.S. coverage, the technology evolution of broadcast satellites, and broadcast satellite weights.