A 75 Watt, 59 to 64 Ghz Space TWT

The design and performance of a high efficiency 70 Watt, 59 to 64 GHz traveling-wave tube (TWT) is described. This intersatellite communications TWT, designated the Hughes Aircraft Company Model 961HA, employs a coupled-cavity slow-wave structure with a two-step velocity taper and a four-stage isotropic graphite multistage depressed collector (MDC). This TWT achieved outstanding beam transmission, 96% with RF. This is the highest power and widest bandwidth device of this type. The tube has 45 dB of gain and 30% efficiency. This TWT is conduction cooled and weighs 13 lbs.