Thermionic peak voltmeters for use at very high frequencies

This paper refers to the two sources of error experienced when using peak voltmeters at frequencies of 20 megacycles per sec. or higher, namely, the error due to resonance and that due to the time of flight of the electrons from anode to cathode in the rectifying diode. In the case of the parallelplane diode the latter appears to impose the severer limitation, and it is shown that very short times of flight are necessary. An approximate method of estimating this error with diodes of other geometric form is suggested, and a convenient arrangement of peak voltmeter for use at high frequencies is described.