TDA0161 metal detector circuit diagram

These metal detector circuit diagrams are based on the TDA0161 monolithic integrated circuit designed to detect metal body detection by detecting changes in high-frequency eddy current losses. For detecting metal, the TDA0161 requires an external LC tuned circuit.

The output signal is determined by the change in supply current. This current has nothing to do with the supply voltage, whether it is high or low, the presence or absence of close metallic objects. This metal detector circuit uses two LEDs to provide a visual indication of the presence or absence of a metal coil around it. To adjust the circuit you need, make sure there is no metal coil nearby and then set the trimmer to "middle position". After that, you need to adjust the trim of the course to turn the LED on and the trimmer to turn the LED off.

The electronic circuitry of this detector operates over a wide range of input voltages from 4 -35 volts. If you want, you can use other values ​​for the CX capacitor and L1 inductor (changing this value will affect the oscillation frequency and detection range).