The Radio Handbook, Twenty-First Edition, authored by William I. Orr, W6SAI, is a comprehensive guide for amateur radio enthusiasts and electronics hobbyists. Published in 1978 by Sams & Co., this first printing edition covers a broad range of topics from basic radio communications to advanced equipment design and testing techniques. Its extensive contents include chapters on direct current circuits, semiconductor devices, vacuum-tube principles, radio-frequency power amplifiers, and specialized amateur communications systems.

This edition features updated and detailed information on HF and VHF power amplifiers, oscillators, transmitters, receivers, antennas, and electronic test equipment. It is a valuable resource for both beginners and experienced operators looking to deepen their understanding of radio technology. The book includes a glossary of terms, nomenclature of components, and practical construction practices, making it an indispensable reference for the amateur radio community.

With its authoritative content and clear presentation, the Radio Handbook by William I. Orr remains a classic in the field, ideal for collectors and practical users alike. The sturdy hardcover binding and Sams publishing ensure durability and quality for long-term use.