When you picture a metal detector, you probably imagine a device that has a long shaft with something that looks like a small steering wheel attached to the bottom end. The user walks along the beach, ...
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How Does a Motion Detector Work?

First developed for World War II, motion detectors have come a long way from the radar that pilots used way back then.
So, you've binged a few treasure-hunting shows and now you're wondering if your own old detector in the garage can find you a pirate chest. One of the first questions that may pop up in your head ...