Apparatus for counteracting the cathode current increase occurring during warming-up in a travelling-wave tube in response to variation in the grid-cathode distance

摘要

Apparatus for compensating the injurious increase of the cathode current occurring during the initial operation period of a travelling-wave tube when, during successive warming-up, the grid first approaches the cathode and then assumes the nominal distance therefrom. The apparatus includes a distance control device measuring the deviation between the actual grid-cathode distance and the nominal distance and generating a control signal proportional to the deviation for reducing the value of the grid voltage.