Remarks on Determining Some Leaky-Flux Filament Transformer Parameters of High-Power Electronic Tubes

A leaky-flux filament transformer is used in a method for restricting the filament switching on current surge. Considering a lossless filament transformer, a correct design formula is derived for the open-circuit secondary voltage of the transformer. This is compared with a formula given in the literature [2], and the relevant error is calculated. Useful universal plots are given which permit a quick determination of the open-circuit secondary voltage. References are given [1] to other details on the design of filament current-surge restricting devices for high-power electronic tubes.