Measured performance of a phase-controlled harmonic-multiplying, inverted gyrotwystron

Summary form only given. This is a preliminary report on operation of the phase-controlled, harmonic-multiplying, inverted gyrotwystron (phigtron) which uses a magnetron injection gun (MIG) (60 kV/10 A), a combined TE/sub 00/ mode-launcher/input-coupler, a Ku-band fundamental gyro-TWT pre-bunching section, a radiation-free drift section, and a Ka-band complex output cavity. Depending on preset operating parameters, the phigtron can be operated either as an efficient, phase-locked oscillator or as a frequency-multiplying amplifier with medium bandwidth. For the oscillator, we obtained 180 kW output, 33% efficiency, 30 dB phase-locking gain, and /spl sim/1 MHz locking bandwidth around 34.4 GHz; widest bandwidth operation gave 100 kW output, 25% efficiency, 30 dB phase-locking gain and 8 MHz locking bandwidth around 34.6 GHz. For the amplifier, 150 kW output, /spl sim/20% efficiency, and /spl sim/35 dB saturated gain were measured. Amplification was in a band of 1.5% around 31.8 GHz.