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The Voice Of The Crystal

How To Build Working Radio Receiver Components

Entirely From Scratch

This is the gateway to finding out anything you'd want to know about my first book, The Voice of the Crystal. Scroll down for a  summary, for a table of contents, and for links to news, reviews, and a photo gallery of projects.!

About The Voice Of The Crystal

To many, crystal radio construction means purchasing electronic components. However, the very best tinkerers can build their own! In The Voice Of The Crystal, author H. P. Friedrichs reveals how to construct all of the necessary components "from scratch".

Inside this volume you will find 185 pages of practical information on the fabrication of electronic components suitable for use in building crystal radio sets. Basic theory and simple analysis is combined with dozens of examples of historical practice, work by contemporary experimenters, and construction details for many instruments fabricated by the author himself.

Inside are discussions and plans for three different homemade headphones, (including one fabricated from cigarette lighter parts,) detectors, fixed capacitors, a rotary variable condenser, single layer, spider web and basket coils, and a precision double-slider coil. Throughout, the author shares his thinking and practical experience in the construction of these devices. The Voice Of The Crystal is profusely illustrated, containing well over 120 photos and hand-prepared illustrations.

ISBN 0-9671905-0-9 Copyright 1999

The Voice Of The Crystal - Table Of Contents

The Challenge * Safety First * Basic Theory * Essential Characteristics Of A Good Headphone * The "Gallows" Headphone * The "Tin Can" * Headphone * The "Cigarette Lighter" Headphone * Essential Characteristics Of A Good Detector * Practical Detector Designs * The "Boom" Detector * Essential Characteristics Of The Condenser * The "Paper Tube" Condenser * Practical Variable Condensers * The "Roofing Metal" Condenser * Essential Characteristics Of The Coil * Thoughts On Practical Coils * Practical Variable Inductors and Coils * The "Crank" Coil * Thoughts On Simple Tuners * Some Thoughts On Antennas And Grounds * Sample Circuits And Assorted Ideas * Useful Formulas and Data * Where To Find Materials * Reference


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Photo Gallery

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(revised - 11/03/2005)