Series Modulation

In this paper it is pointed out that the type of modulating system used in any given case depends to some extent upon the particular type of service involved. The limitations of existing types of control are discussed, and a detailed theoretical and experimental investigation of the so-called series type of modulation is reported. Operating data, in the form of graphs, are presented for those existing tubes which because of their characteristics are adapted for use in connection with this type of control. The advantages and limitations of the series method are outlined, and the desirability of an improved tube for use as a series modulator is stressed.