Project Echo: 960-mc, 10-kw Transmitter

This paper describes the 960 mc, 10-kw output radio transmitter used in Project Echo.* The main transmitter unit and its input stage driver unit are standard commercial equipments supplied by the Federal Telecommunication Laboratory, f These units were selected from a number of those available, since they came closest to our particular requirements for wideband FM transmission. These general requirements were that the transmitter could (a) deliver 10 kw of RF power into a 50-ohm load at a frequency of about 900 ± 2 mc; (b) be frequency-modulated over the audio frequency band with deviations of ±200 to 300 kc; and (c) be used with other types of modulation such as single-sideband (SSB), double-sideband (DSB), interrup* Although this equipment was designed by the Bell System as part of its research and development program, it was operated in connection with Project Echo under Contract NASW-110 for the National Aeronautics and Space Administration. f Division of International Telephone and Telegraph Corporation. 1041