First operation of Ka-band high-current relativistic gyrotron

The results of the first operation of a pulse Ka-band gyrotron with output radiation power more than 110 MW are presented. The gyrotron was excited by electron beam with a current of up to 2 kA and particle energy of up to 500 keV, formed by an explosive emission cathode with subsequent transverse velocities pumping in a non-uniform field produced by a short coil (kicker) to a state with a pitch-ratio of about 1.