A coil of wire (the transmitter) is energized with an alternating current, creating a fluctuating magnetic field. When this field encounters a conductive object, it induces eddy currents in that object. Those eddy currents generate a secondary magnetic field, which is picked up by a receiver coil.
The detector’s electronics compare the transmitted and received signals to distinguish metal targets from background mineralization. When a metal object is detected, the unit alerts the user via audio tones, visual indicators, or both.
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