Development of multi-frequency gyrotron for ITER and DEMO at QST

Quad-frequency oscillation from 100 GHz to 200 GHz was demonstrated using ITER gyrotron at QST. Those RF beam passed through the center of the gyrotron window and good couples to transmission line were obtained for each oscillation. The mega-watt-class power was obtained for all frequencies. Validation of gyrotron for a demo reactor is numerically started on the basis of our multi-frequency gyrotron.