What Happened to Cat’s-Whisker Detectors? The Crystal Contact Behind Battery-Free Early Radios
895 views · Sep 30, 2026 · People & Blogs
Comments · 4
@craxd1 · 6 hours ago (edited)
Does anyone remember building a crystal set as a kid? I did when I was about ten, and that led me into the electronics field I pursued.<br><br>You should do one on the old copper oxide diodes. You'll find these in the oldest tube testers, and they're important. I have the original book by the man who invented them in 1920.
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