Powerful second-harmonic gyrotron oscillator

Experimental results from a study of second-harmonic gyrotron oscillator are reported. A steady second-harmonic cavity emission has been observed at 28 GHz and waveguide mode TE/sub 02/. A peak power of approximately 30 MW has been reached with approximately 9% efficiency. For better understanding of the generation mechanism additional gyrotron experiments have been carried out with a similar cavity without a cutoff section at the exit, operating at the fundamental cyclotron harmonic.<
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