Cathode activity measurement: A modification of the dip test

A method of cathode activity measurement which yields fundamental cathode parameters has been developed. Basically, it is a modified dip test and consists of plotting cathode current vs cathode temperature. A simple geometric analysis of the data plot yields data that can be related from one tube to another and to the cathode work function. Thus, experience gained by this simple and rapid technique may be translated from one tube type to another. This technique can be used to obtain the work function as a function of cathode temperature and a method is suggested for obtaining work function as a function of current density.