The circuit diagram of the door opening alarm is shown in Fig. 1. It is built around hall sensor MH183 (IC1), pnp transistor BC557 (T1), npn transistor BC547 (T2) and a few other components.

Here is a simple tilt sensor based switch circuit diagram which is built using a mercury based tilt sensor. This sensor is place on a box, so when someone opens the box, the buzzer connected with the ...

Ultrasonic Sensor Module: Ultrasonic sensor HC-SR04 is used here to detect the presences of any person at the door. The sensor module consists of ultrasonic transmitter, receiver and the control ...

New Sensor Bares Faults In Smallest Possible, Most Advanced Circuits Date: May 12, 2003 Source: Brown University Summary: A new scanning microscope developed at Brown University can uncover ...