A 500 GHz TE85 mode continuously frequency-tunable gyrotron has been designed, fabricated and investigated experimentally. In the experiment, the gyrotron operates at the second cyclotron harmonic stably. The operating frequency is tuned by means of adjusting the operating magnetic field or the beam energy. The variation of the output power is also investigated. It is found that when the operating magnetic field is changed, the frequency-tuning range is much bigger than that when the beam energy is changed.

Beam energies; Experimental investigations; Frequency tunable gyrotrons; Frequency tuning range; Operating frequency; Output power; Second cyclotron harmonics

University of Electronic Science and Technology of China