Resonant cavity vircator driven by a thermionic cathode electron beam gun

A resonant cavity vircator (virtual cathode oscillator) driven by an electron beam emitted from a broad-area thermionic cathode is tested. Narrow-bandwidth (1.0 MHz at the -3 dB level) excitation of the TM/sub 023/ mode of a cylindrical resonant cavity is observed at a frequency of 986 MHz with a pulselength of 1.2 mu s. The single-cavity-mode excitation is attributed to the constant-voltage and -current electron beam emitted from the thermionic cathode.<
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