Bibliography

N. N. Khlebnikov. Collection of Problems and Exercises for the Course on Electron Vacuum Devices. Edited by V. F. Vlasov. VKAS edition. Leningrad, 1948, 188 pp. Price not indicated.

In the practice of higher-education teaching, a proper combination is needed of lecture-theoretical material, calculations and exercises, and, finally, laboratory problems. If, for the theoretical courses on electron vacuum devices, we now have a certain number of corresponding textbooks and monographs, then in laboratory work something—although, admittedly, not very successful—has already been done in the past as well; as for calculations, however, almost nothing has been published on them. In this connection, in those higher educational institutions where due interest was shown in this kind of instructional work, improvisations had to be made—for example, this was the case at Kiev State University, where, as a result of three years’ practice, about 120 problems and calculations on various problems of electronics were compiled. The publication of the present book shows that work of this kind was also carried out at other higher educational institutions and, in pleasant contrast to other cases, was arranged in the form of a systematic printed edition, which is thus unique in its way.

The present book is divided into two sections: the first (pp. 5–129) contains problems and exercises; the second (pp. 130–187) contains solutions to some of the more difficult and interesting problems. The first section, which contains a total of 305 problems, is divided into 10 chapters, of which 8 are devoted to all kinds of electron tubes: from the simplest to multi-grid and UHF tubes inclusive; the remaining 2 chapters are devoted to photocells, electron-beam devices, and gas-discharge devices. Each of these chapters is divided into problems proper and then into exercises; the latter are review-and-control questions on the theoretical course. From the style of these exercises and problems and from the general plan of construction of the whole book under review, it is clear that it is based mainly on V. F. Vlasov’s well-known textbook Electron Vacuum Devices (2nd ed., 1949).

Turning to a more detailed consideration of this book, the following may be noted.

As is clear from what has been said, the main content of this problem book is devoted to various electron tubes. These problems, by their character, fall into 2 groups: in the 1st, calculations connected with physical processes in tubes are considered (calculations of cathodes, motion in the interelectrode space, static characteristics, electron currents in various elements of the tube, calculations connected with phase focusing, etc.). The 2nd group includes problems connected—

associated with the dynamic operating mode of the tube, i.e., with its external characteristic as an element of a definite electrical circuit. In all, these eight chapters contain 259 problems. These problems, as a rule, are very good and interesting; they cover a wide range of all kinds of modern tubes and have an original character. Here we encounter both comparatively simple examples, especially at the beginning of the book, and, subsequently, complex combined calculations. Solving all these problems will undoubtedly be of very great benefit, especially for students who in the future will deal not only with the operation of electronic tubes, but also with their design and development.

The two chapters (46 problems) devoted to photocells, cathode-ray devices, and gas-discharge devices have a somewhat different character; here we encounter chiefly problems of the second group, i.e., those considering the behavior of the corresponding devices as elements of an electrical circuit; this applies especially to gas-discharge devices. It should be noted that insufficient attention is devoted in a number of modern textbooks on electron-vacuum devices to a detailed account of the physics of modern textbooks on electron-vacuum devices (which, it seems to me, is wholly undeserved). Since gas-discharge devices, and above all arc-discharge devices, have firmly entered modern practice, serious study of the physics of gas discharge must be introduced into the corresponding courses on electron-vacuum devices, however difficult this may at first glance seem.

What has been said here in no way diminishes the great merits of the book under review, especially if one bears in mind that it is the first and so far the only specimen of literature of this kind. The author’s initiative, having realized so successful and useful a specimen of such literature, should be welcomed in every way. This book should undoubtedly be published in a sufficiently large edition to make it accessible to the wide circle of teachers and students of this discipline. Before that, however, it should be somewhat modified: the sections devoted to the physics of photoelectronic, cathode-ray, and especially gas-discharge devices should be expanded. Then it should be supplied with the principal reference formulas and graphs needed for calculations, as well as with the values of physical constants. Finally, it seems to me that it should omit the so-called exercises, i.e., control-and-repetition questions, which only spoil the general style of the book. Published in such a form, this book will undoubtedly be a very valuable teaching aid. So successful an example of this book makes still more urgent the question of publishing a collection of problems and calculations in physical and technical electronics in the broad sense of the word.

N. D. Morgulis