Low-cost concealed wire detector circuit

The utility model discloses a low-cost concealed wire detector circuit which comprises a potentiometer RP1, a double-base diode Q1, a resistor R1 and a triode V1. One end of the resistor R1 is connected with an antenna A and the emitter electrode of the double-base diode Q1; and the other end of the resistor R1 is connected with a resistor R2, a capacitor C1, a capacitor C3, the cathode of a diode D1, a buzzer B and the negative pole of a power supply E. The concealed wire detector circuit is simple in structure and few in component, so that a produced detector is small in size and convenient to carry; meanwhile, the circuit abandons complex and only basic electronic component design, so that anti-interference performance of the circuit is greatly enhanced; and the detector has the advantages of being low in cost, convenient to carry and resistant to interference.