Methods of diagnosis and prediction of modern thermo cathodes

Surface areas with low emissions are a major source of noise thermo cathodes, playing the role of defects. Dependence the level of the shot noise component and flicker noise component from the anode voltage can determine the noise parameters with highly informative for predicting the durability of hot cathode operation. Durability and a resource of hot cathode can be predicted based on a study of degradation of their emission properties in the forced mode.