Excitation of “monotron” oscillations in klystrons

A general method for calculations of starting currents of modes in klystron cavities is developed. This method allows one to determine the threshold for excitation of so-called monotron oscillations in klystrons having an arbitrary geometry of cavities and an arbitrary cross section of an electron beam. The method is used for evaluating the starting currents of monotron oscillations in a sheet beam, X-band klystron, which is currently in the design state at Calabazas Creek Research Inc.