Status report on the environmentalization of traveling-wave tubes

This paper describes the effects of various environments on the performance of periodic-permanent-magnet focused traveling-wave tubes, the design considerations required to enable the tubes to operate under changing environments, and the means of determining satisfactory compliance with environmental specifications. Design considerations discussed include the ruggedization of various component structures, temperature compensation of periodic-permanent-magnet stacks, and the reduction of the effects of high altitude and humidity on tube operation. Equipment and test methods used to evaluate tube performance under simulated environmental conditions are described and both present and anticipated environmental capabilities of several traveling-wave tube designs are discussed.