Independent gain and bandwidth control of a traveling wave maser

摘要

An X-band traveling wave maser of the folded-comb type is provided with two figure-eight coils for gain and bandwidth control. One figure-eight coil covers the full length of the comb structure for bandwidth adjustment of an external magnetic field. The other figure-eight coil covers a central half of the comb structure for independent gain adjustment of the external magnetic field. The half of each figure-eight coil at the turn around end of the comb structure is oriented to aid the external magnetic field, and the half of each figure-eight coil at the input-output end of the comb structure is oriented to buck the external magnetic field. The maser is pumped in the push-push mode with two different frequencies.