A frequency-locked, high power, X-band dielectric Cerenkov maser

A high-power frequency-locked dielectric Cerenkov maser oscillator is presented. The device consists of an annular electron beam traveling down a dielectric-lined waveguide (wall radius 1.74 cm, liner thickness 2-3 mm, linear in =10). A 100 kW input signal is injected into the drift tube between the diode and liner, through a rectangular TE/sub 10/ to cylindrical TM/sub 01/ mode converter. When operated with a beam current of 500 A and a total output power of 13 MW, the device displays no RF quenching through the full width of the 100 ns beam pulse. Two higher current cases with power as high as 280 MW but severe RF quenching are presented. The results are compared with linear theory, and quenching mechanisms are discussed.<
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