A metal detector used to be an entirely analogue instrument, an oscillator whose frequency changed with the inductance of its sense coil when a piece of metal approached. [Łukasz Podkalicki ...

it was time to build the rest of the metal detector. Look ma, no MCU! The sensor coil was made by salvaging the wire from an old fluorescent lamp ballast and winding it around the lid of a bucket ...

Sahd Metal Recycling in Columbia celebrated Earth Day a couple days early this year. Staff members conducted walking tours for the public of the company’s Lancaster Avenue metal recycling ...

This Garrett metal detector combines ease of use and versatility in a way that is unparalleled. It highlights an ACE Environmental Coverup, Easy Stow headphones ... a single coil which emits more ...

You have once bought a metal detector ... a 9” waterproof concentric coil. The concentric coil is the coil type dominating entry-level detectors because of its reasonable price. That’s also the reason ...

CNET’s expert staff reviews and rates dozens of new products and services each month, building on more than a quarter century of expertise.