The technique of frequency measurement, and its application to telecommunications
J.E. Thwaites, F.J.W. Laver · The journal of the Institution of Electrical Engineers. Part 3, Communication engineering · 1942
Rigid frequency control has become a necessity in radio broadcasting and indeed in all forms of telecommunication, and the art of frequency measurement has likewise become of great importance. The improvement in frequency standards which has taken place in recent years is briefly outlined in this paper, and some of the methods which may be used to obtain accurate frequency measurements in terms of the improved standards are described.