Design and experimental study on a 263 GHz frequency-tunable gyrotron

A 263 GHz frequency-tunable gyrotron has been designed and experimental studied. The gyrotron resonator is traditional three-section cavity. The operating frequency and the output power with respect to the operating voltage, operating magnetic field and the beam current are investigated experimentally. It is found that the operating frequency changes from 263.39 GHz to 264.84 GHz and the frequency-tuning range is about 1.45 GHz, the variation of the output power is from 26 W to 463 W when the operating voltage is fixed at 20 kV and the beam current is fixed at 0.8 A but the operating magnetic field changes from 9.59 T to 9.82 T. When the operating voltage increases from 14.4 kV to 22.2 kV at a fixed operating magnetic field of 9.65 T, the operating frequency decreases from 263.68 GHz to 263.40 GHz and the and the frequency-tuning range is 0.28 GHz. Meanwhile, the output power is changed from 52 W to 424 W. When the beam current increases from 120 mA to 880 mA but the operating magnetic field is fixed at 9.65 T and the operating voltage is fixed at 20 kV, the output power increases from 21 W to 277 W and the operating frequency increases from 263.396 GHz to 263.425 GHz, the frequency-tunable range is 0.029 GHz.