This book was developed from the lecture notes of a special war time training course given at the Graduate School of Engineering, Harvard University, for officers of the Signal Corps who were graduate ~lectrlcal engineers. It is therefore somewhat abbreviated and designed to emphasize essentials for immediate practical application. It also reflects in high degree the results of experience in methods of presentation for such a course.
There are four chapters, comprising the work. The first on transmission lines is concerned with the behavior of lines at radio frequencies, their use for the transmission of power, the use of short sections of line as reactances and for impedance matching, their use in the measurement of frequency, and the measurement of impedances at radio frequencies. Antennas, which is the beading of Chapter Two, opens with a qualitative introduction to general electromagnetic theory and proceeds through the topics of the driven antenna as a circuit element, coupled antennas and transmission lines, the receiving antenna as a circuit element, electromagnetic field of antennas and arrays, and closed circuits as antennas. The same general principles are applied in Chapter Three to circuits of a different type. Here, ultrahigh frequency circuits are discussed, including the coaxial line, resonant and nonresonant circuits. The last chapter is devoted to wave propagation. This is somewhat brief. It brings out the essential facts governing ground-wave an d sky-wave propagation, and relates these to well known scientific principles to show that the newly described phenomena are in reality wholly natural and understandable. This treatment is largely non-mathematical.
In the back of the book are problems for exercise, many of them with answers, and a subject index. There is a logical sequence to each treatment in the book. It should have considerable post-war use as a text and reference.
R. H. OPPERMANN.