One of my new obsessions is building metal detectors. BFO’s are great for “probes” (ie close range detector for searching the larger area scanned by your bigger detector).

An Arduino can measure time, a coil and a resistor will create a delay proportional to the circuit values, and metal around the coil will change the coil’s inductance.

A new Instructables page has been created to make an eco-friendly DIY metal detector using an Arduino Mega just been combined with a 3.2 inch TFT LCD ...