Really reduced frequency detectors run on one frequency at a time. Based on Lubbert and Ross, they’re designed for entry-level hobbyists in search of cash and jewelry, but gained’t work effectively for gold prospecting or scanning saltwater beaches. The capacitive sensor’s output is connected to Arduino UNO’s analog pin#A0. This https://deanuwsmd.shotblogs.com/the-basic-principles-of-types-of-metal-detector-sensor-41257377