Electronics Pergamon Press 1965. p. 615. Printed in Great Britain
envisage making use of semiconductor devices will wish to supplement this chapter with a reading of a more detailed treatment of circuit design. The final chapter is entitled “Miscellaneous semiconductor devices” and includes a brief description of the properties of tunnel diodes, controlled rectifiers and field-effect transistors. Each chapter has several associated numerical problems, but only a brief bibliography is supplied. The book is well printed, apparently free from typographical errors and at 18s. it represents excellent value for money. It deserves a place on many bookshelves.
M. J. MORANT, Introduction to Semiconductor Devices, Harrap, London, 1964, pp. 126. 18s. THIS is a very useful little book that would be of interest to not only students of electrical engineering and physics but also those professional workers who were brought up on thermionic valves and who now find themselves using semiconductor devices with little more than a pictorial knowledge of the basic physical processes involved. The author concentrates, in four of the six chapters, on the physics of semiconductor materials and semiconductor devices and in so doing establishes clearly that the monograph is aimed primarily at those readers who are looking for a satisfactory explanation of the microphysical processes involved in the operation of semiconductor devices without having to delve into textbooks on pure semiconductor physics, but who seek a more closely argued account than is available in the introductory chapters of most “applications” books. This account is lucid and eminently readable and although the mathematics used will be well within the grasp of most readers, the treatment is sufficiently rigorous to give the reader easy confidence in the relationships derived. Semiconductor materials have so much greater diversity of application than thermionic emission ever did that a knowledge of the fundamental processes involved and an ability to make quantitative comparisons between device materials is important for any worker who hopes to understand new devices, or who is called upon to evaluate the potentialities of, say, the tunnel diode in a particular application. It is in this area of activity that the first four chapters of this monograph will prove their worth. Chapter 5 discusses the transistor as a circuit element and the four terminal network h parameters are derived in terms of a low-frequency equivalent circuit. The chapter continues with a brief discussion of high-frequency effects, a short description of the construction of three types of transistor and a few notes on the use of the transistor as a switch. Many of those readers who
R. N. THOMAS Bedford College, London, N. W.1
Solid-State Electronics pp. 615-616. J.
Pergamon Press 1965. Vol. 8, Printed in Great Britain
J. DOWNING, Modulation Systems Prentice-Hall, 1964. pp. 214, 66s.
IT IS the purpose of this book to present a unified approach to the analysis of established forms of communication system, using statistical methods and the now well known mathematical representations for random noise. The first section of the text forms a very concise but valuable outline of probability theory, spectral analysis and correlation theory, and the mathematical representation of narrow-band Gaussian noise. Readers who have some knowledge of the above topics will appreciate the clear manner in which they are presented and will also find the section most useful for reference purposes. Other readers will probably need to refer to some of the sources mentioned in the text for a full treatment of certain topics. The next section deals with the effects of noise on the performance of amplitude modulation and angle (phase or frequency) modulation com-