Build Your Own Crystal Shortwave Receiver
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This project combines two popular themes from radio history—crystal radios and shortwave (SW) listening. It's the latest addition to our "Radio Wrinkles" section, designed from scratch by resident engineer Walter Heskes.
Despite all of the advances in modern electronics, there are thousands of crystal sets in daily use throughout the world. The fidelity of tone and clarity of crystal rectification are hard to beat. What's more, crystal sets are absolutely free! A crystal receiver is powered solely by the radio waves that it pulls from the air.
We dubbed this inexpensive radio the "EconOceanic" in honor of the legendary Zenith TransOceanic family of shortwave radios. It tunes the AM broadcast band, from .5 MHz to 1.6 MHz, and most of the shortwave band, from 1.7 MHz up to about 17 MHz.
There's plenty of SW activity in these bands, so you'll hear lots of different voices, a mix of languages, and even music. In addition to powerhouse stations such as the BBC, you'll also hear non-commercial amateurs, some of whom broadcast using the dits and dahs of International Morse Code. And don't forget to set your wristwatch by the precise WWV time signals. They appear at exact multiples of 5.0 MHz across the SW bands. Listen for the calibration beeps and periodic time announcements.
We hope you enjoy this project. If you build an EconOceanic, send some email to let us know how it worked out. Walter can be reached at walterh@interworld.com.
Copyright 1997 Walter Heskes and Philip I. Nelson, all rights reserved. This radio construction project, including all descriptions, diagrams, photos, and the underlying electronic design, is published here for the noncommercial use of radio hobbyists. You may print and reproduce these project instructions for your personal use. Commercial use of this material is strictly forbidden.