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] shows us ...

Here is a VLF receiver tuned to 300 kHz designed to detect the crackle of approaching lightning. A bright lamp flashes in sychrony with the lightning bolts indicating the proximity and intensity of ...

The metal detector circuit shown here must represent the limits of simplicity for a metal detector, yet the design works surprisingly well. It uses just one 40106 hex Schmitt inverter IC, a capacitor ...

A traditional early project for someone discovering a love for electronics has been for many years a metal detector. This would mean a few transistors back in the day, but today it’s more likely to ...

Armed with metal detectors, curious explorers are finding historical objects every day. For example, Bob Podhrasky, COO, senior vice president, and director of engineering at metal detector ...