The heart of this diy metal detector circuit is the CS209A IC. The metal detector is built with one 100µH coil that has 40 mm in diameter and is made of 50 turns/0.4 mm wire. CS209A has one oscillator ...

The working principle of this cheap and easy to build metal detector circuit consists in mixing two equal frequencies which causes a low-frequency interference. When one of the oscillators become ...

Have you ever found yourself suddenly in need of finding a small metal object hidden in the woods? No? Well, neither have we. But we can’t say the same thing for [zaphod], who’s family was hoping to ...

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.