How to design an Arduino-based RLC metal detector using an RC …
The RC-A-354 sensor is a popular metal detector that uses an RLC circuit. It can search metals up to a distance of 3cm. At this range, it's useful for security checks or collecting metallic trash. This sensor has a copper coil about one-meter-long that serves as the inductor. It has: Two capacitors: 100 and 47uF.