A Developmental Wide-Band, 100-Watt, 20 DB, S-Band Traveling-Wave Amplifier Utilizing Periodic Permanent Magnets

A developmental, 100-watt, S-band traveling-wave amplifier utilizing ceramic "periodic" permanent magnets to focus the electron beam is described. The minimum peak power output of the tube is 100 watts at a gain of at least 20 db at frequencies from 2,000 to 3,800 magacycles per second. At lower power levels, a gain of 36 db has been measured in the center of the frequency band. The operating voltages for the amplifier are below 4,000 volts. The use of \´\´periodic" magnets in place of conventional solenoids or permanent magnets producing uniform magnetic fields effects a considerable reduction in the weight and size of the focusing system. Constructional features of the tube which permit operation with the \´\´periodic\´\´ magnet are discussed. The rf characteristics of this amplifier are evaluated, and the complete "package" assembly is described.