This book was written by a long-time member of the Xtal Set Society, Mr. Phil Kinzie. It chronicles the fascinating history and development of the crystal detector, including the reasons for its brief dominance of the radio market after the turn of the century. Starting with the discovery of solid-state rectification and then through the development of the crystal detector the reader learns about great inventors such as Pickard, Braun, Dunwoody, and others. Radio fundamentals such as antennas, ground, lightning protection, tuned circuits, and detection are covered for the beginner. The unending compromise between selectivity and sensitivity is discussed for the crystal set designer. Advanced topics such as the use of multi-tuned circuits and wave traps follow for the serious experimenter. Great background for any crystal radio enthusiast.