Acxico 1Pcs Metal Detector Module DC 35V NonContact Sensor Module

Principle description: Q1, L1, L2, C2, C3, R1, W form a high-frequency oscillation circuit, and the potentiometer W can be adjusted to change the oscillation level gain, so that the oscillator is in a critical oscillation state, that is, the oscillator is just started to vibrate. Q2 and Q3 form a detection circuit. When the circuit is oscillating normally, when the oscillating AC voltage exceeds 0.6V, Q2 will be turned on in the negative half cycle, and the C4 discharge will be short-circuited, resulting in Q3 being cut off; when the detecting coil L1 is close to the metal object,The eddy current will be generated in the metal conductor , the energy loss in the oscillation circuit will increase, the positive feedback will be weakened, the oscillation of the oscillator in the critical state will be weakened, and the minimum energy required for the oscillation can not be maintained and the vibration will be stopped, so that Q2 is cut off and C4 is charged by R2 . Q3 turns on and pushes the buzzer to sound. According to the sound, it can be determined whether there is a metal object under the detecting coil. Detection effect: Easily and stably detect metal objects such as metal coins, steel plates, iron plates, aluminum plates, computer CDs, etc., which are about 2.5 cm away from the coil plane (circuit board).Through actual tests, the maximum detection distance can reach 5CM, and can detect mobile phones, keys and coins in the pocket. Example : if you want to detect whether there is a car passing on a road surface, because the car chassis is 0.5 meters or more from the road surface, plus cement will bury the depth of 5-10CM, therefore, buried in the ground diameter of 1 meter coil can be stable, accurate and reliable detection of whether there is a car on it, which is in highway traffic statistics, and so on. Parking area statistics are of great practical value. Package Includes: 1Pcs