This circuit triggers a Sonalarme when the LED used as a sensor receives light. The circuit was found in an old documentation, but the components used are all current.
Incandescent lamps and heaters can be controlled by a low power switch using this circuit. The...
August 2016 - It can be found at Mouser Electronics the new sensors light to digital OPT3002 from...
This alarm uses several sensors that directly trigger a sensitive relay. A larger relay can be...