Radio physics course [antikvár]

PREFACE This second revised and enlarged edition, represents the result of an effort to include in a single book, all of the material required for a complete up to date course in radio. It has been written especially for use as a text book for radio courses in technical high schools, trade schools, and by custom radio set builders and the thousands of technical and nontechnical persons who desire to gain an insight into the working of radio receivers, sound amplifier equipment, photoelectric cells and devices, television equipment, and sound motion pictures, either for their own knowledge and satisfaction or as a means of earning a livelihood. The book is also adapted for home study by those who cannot attend a school. The title "Radio Physics" has been applied in the sense that physics is mainly an explanation of common things. Radio Physics is then an explanation of the common things in radio. Every attempt has been made to bring this edition up to date with descriptions and illustrations of the modern forms of radio equipment which are now being employed. Those readers who are familiar with the first edition, will quickly see that all obsolete material has been dropped in this edition. Even though this has been done, the addition of a complete electrical course for radio students, and the thorough revision of the radio section and addition of new material which was necessary to keep the book up to date, has resulted in a large increase in the number of pages. Every attempt has been made to further the usefulness of the book as a text on radio for the use of even the most non-technical persons. The topic sections are numbered for easy reference, and larger more readable type has been used throughout this edi-tioh. Enough carefully selected review questions for the questioning of entire classes, have been included at the end of each chapter. In the preparation of the text, the requirements for a thorough practical knowledge of modern radio, have constantly been kept in mind. Involved technical discussions have been omitted wherever possible. An attempt has been made to present the subject matter as clearly, and in as simple language, as possible A complete course in electricity, and some work in sound, has been added, as a result of the suggestions of a large number of radio instructors who have used the first edition in their courses. The author has always felt that a thorough training in the fundamentals of both d-c and a-c electricity should first be obtained, before making any serious attempts to study radio. This is even more necessary now than ever before, because of the refinements in design and almost universal ix.