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, we are going to build small circuit named metal detector circuit which is used to check the persons in shopping malls, cinema halls, etc. to ensure that person is not carrying any explosive ...

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 ...