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Take Me To The Gadgetory!
Knock Box (repeats rhythm used when knocking on the lid)

Posted January 14, 2013 by Chris

“Doing some initial research on automatic door knockers, I came across an excellent post describing a secret knock-detecting door. This looked like a perfect starting point, so I decided to recreate it with my own hardware. To simplify input and output, I started with a simple button for input and an LED for output. I took the code provided and modified it so that it replayed rather than validating the recorded knock pattern.”

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