G. Möller, Electronic Tubes and Their Applications, translated from the 3rd German edition, edited by Prof. S. E. Khaikin, GTTI, 1934, 251 pp.

Despite the relatively large number of books devoted to electronic tubes (Barkhausen, Morkroft, Aseev, Sharov, and others), the appearance in Russian translation of the well-known book by Möller—with the method of oscillation characteristics he created, which has found wide application in radio engineering—may be warmly welcomed, all the more since the translation was made from the latest German edition, considerably revised in comparison with the earlier editions. The first chapter acquaints the reader with the basic properties of the electron discharge in vacuum and with methods for controlling it (two- and three-electrode tubes). The second chapter considers the operation of a tube as an amplifier. The central part of the book is the third chapter, which deals with the tube generator. The author develops in detail the method of oscillation characteristics, first as applied to the theory of the generator without taking grid currents into account, and then with these currents taken into account. Further, the theory of entrainment and a number of special questions are briefly considered (Barkhausen–Kurz oscillations, the quartz generator, etc.). The fourth chapter is devoted to the detecting action of the tube and its applications. Finally, the last chapter considers the physics of amplifying tubes, the conditions of motion of electrons in va-

in a vacuum in the presence of space charge, the conditions for the emission of electrons by various types of cathodes, and a number of particular questions with which anyone working with tubes must become acquainted.

The book is richly illustrated with various well-chosen numerical examples that facilitate the assimilation of the material presented.

The book demands considerable independent work from the reader, but the labor spent in reading it is repaid by the rich material it contains.

In the preface to the book the editor points out that the method of oscillatory characteristics does not make it possible to resolve all questions connected with the study of the processes occurring in a tube generator, since the nonlinearity of the characteristics requires the application of another mathematical apparatus (the works of Andronov, Witt, the editor, and others). However, new methods, requiring extensive mathematical knowledge and still insufficiently developed, cannot at present be used by broad circles of engineers and technicians, whereas the mastery of the method of oscillatory characteristics, which makes it possible to solve a whole series of practical problems, is fully accessible to all workers who know the fundamentals of higher mathematics and are able to operate with complex quantities. Therefore one may expect that Möller’s book will prove to be a useful manual for Soviet radio engineers and physicists.

H. Malov