The objective of the GoldPic 3 project is to detect coins and jewelry in shallow water and on the beach by optimizing the timing and circuitry for detecting small items. Using readily obtainable low ...

If you think of a metal detector, you’re probably thinking of a fairly simple device with a big coil and a piercing whine coming from a tinny speaker. [mircemk] has built a more modern adaptation.

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 ...