The Ground Station High-Power Traveling-Wave Tube

This paper describes the design of the M4040 2-kw CW travelingwave tube amplifier which was developed specifically for communications applications. It was used as the final power amplifier in the Telstar transmitters at Andover, Maine, and Pleumeur-Bodou, France. It was necessary for the Telstar amplifier to meet the requirements shown in Table I. The M4040 was designed to have sufficient instantaneous bandwidth to operate anywhere in the communications band from 5.925 to G.425 gc. The design approach was a conservative one aimed primarily at delivering an operable tube in time for the Telstar experiment. The development time was approximately 18 months. In describing the M4040, we shall discuss only briefly its mechanical aspects. The prime intent is to present electrical design and operating information which may be applicable to future high-power traveling-wave tube development. Topics concerned with the electrical design of the electron gun, the beam collector, and the slow-wave structure will be discussed. Finally, some performance characteristics will be presented, accompanied by comments on the tube operation. 1829