This home smoke detector circuit warns the user against fire accidents. It relies on the smoke that is produced in the event of a fire and passes between a bulb and an LDR, the amount of light falling ...

Protect your home with confidence by learning how to properly wire a combination smoke and carbon monoxide detector. This clear, step-by-step guide covers safety tips, tools needed, and how to ensure ...

At the heart of this ultra simple smoke alarm is H21A1, which is a photo-interrupter module consists of a gallium-arsenide infrared LED coupled to a silicon phototransistor in a plastic housing. The ...