Pulse monitoring circuit for travelling wave tube - samples each pulse edge to disconnect tube to prevent multiple impact damage

摘要

The monitoring circuit uses two pulse sampling stages to sample each individual delay line current pulse or each demodulated HF output pulse at two successive time points (T1, T2) corresponding to the leading and trailing pulse edges. The sampled values are fed via an intermediate store to a comparator with the travelling wave tube disconnected if a disparity is detected. Pref. a switch allows the sampling stages to be selectively used to sample either the delay line current pulses or the HF output pulses. The sampling points (T1, T2) and the sampling duration are pref. optimised via a control circuit in response to the pulses being sampled. The monitoring circuit prevents damage to the tube due to the multipacting effect.