Suppression of the slot oscillation mode in coaxial magnetrons the millimetric range wavelengths

Methods for a slot oscillation mode reactive suppression in coaxial magnetrons (CM) are considered. The limitations of the existing methods to calculate the slot - type frequency are presented. One modified version of calculations and one novel method applicable to the anode slow-wave system whose thickness of the peripheral wall is over 0.1λ_v are shown. Reactive “destruction” of the HF-field space harmonic of slot-type oscillation is considered in the process of manufacturing rectangular coupling slots of a variable height.