Electron ballistics in high-frequency fields

This, the final lecture of a series on Electron Ballistics, is not a summary of the material which has been previously presented but rather it is an attempt to show how the ballistic approach can be extended to the analysis of high-frequency devices. Much that might otherwise be said about ultrahigh frequencies cannot be said because of secrecy requirements. However, there is considerable material which can be presented, within the limits of the necessary security regulations, which may be of interest to those who are not already well acquainted with the subject. I will, perforce, not be able to say anything specific about actual devices utilizing the principles to be discussed.