This Circuit can compare the Light level in an area. It uses a PN Photodiode as the light sensor and IC CA3140 as voltage comparator. The circuit is ideal as the front end of burglar alarm circuits.

This simple water level indicator will activate an active buzzer (e.g. BeStar BPT-23CX ) in order to make a noise when a certain level of water is being reached. Because the water sensor and the ...

Researchers at Yokohama National University have created a liquid-based tilt sensor that only needs simple interface electronics – some ... water sit in a ring around the edge if the sensor is level, ...