Possibilities for multifrequency operation of a gyrotron at FZK

We investigate the possibility of multifrequency operation of a 140-GHz gyrotron, which is designed to operate in the TE/sub 22,8/ mode at 140 GHz and the TE/sub 19,6/ mode at 111 GHz or the TE/sub 17,6/ mode at 105 GHz, for which existing equipment can be used. The present calculations compute beam properties for a given set of coil currents, accelerating voltage and current, and then use these beam properties to compute the output power and efficiency. These calculations are performed separately for each mode.