Homemade motorcycle anti-theft alarm horn circuit diagram

Homemade motorcycle anti-theft alarm horn When someone moves the car, the vibration sensor ZC receives the vibration signal, which is amplified by IC1D, and then couples the low-level signal to the input terminal of IC1C through the differential circuit composed of C3 and R7, and the output terminal outputs high The level "l" provides power to the four-sound integrated circuit IC2 through R8. The alarm sound emitted by IC2 is driven by V2 and then amplified by V5 to produce a sound. At the same time, the "1" signal on pin 10 passes through D2 and puts pin 12 on "l" to block the input terminal. Therefore, IC1D can keep pin 11 outputting low level "0". C3 and R6 form a differential circuit. As time goes by, Extended, the potential of pins 8 and 9 rises. When it rises to the input threshold of IC1C, IC1C flips, outputs "0", the alarm stops, and enters the alert state. Lead 3 connects to the positive power supply provided by the car key. Lead 4 is connected to the horn switch.