[Dzl] starts his write up with an explanation of how most oscillator based metal detectors work. This one differs by using an Arduino to read from the metal detecting coil. The circuit starts with ...

The same holds true for a lot of microcontroller designs including [rgco’s] clever metal detector that uses very little other than an Arduino. The principle of operation is simple. An Arduino ...

Using motion detectors ... block any heat signatures approaching from the side. Of course you can use multiple sensors and outputs to trigger different effects depending on your needs. The Arduino ...