The frequency multiplication effect in a gyrotron operating under conditions of a large excess of the operating current over the starting value (large supercriticality) was studied. It was shown that in a gyrotron with an operating frequency of 0.5 THz at the first cyclotron harmonic in the frequency multiplication mode at the sixth cyclotron harmonic it is possible to excite random sequences of ultrashort pulses in the range of 3 THz with a peak power of up to 200 W, which is two orders of magnitude higher than the background value.
Ginzburg et al. (Wed,) studied this question.