This simple optical alarm circuit was found in the 1991 Electronics Experimenter Handbook. The circuit uses a lamp as the emitter but can use LEDs.
This high sensitivity receiver of 30 nW was found in documentation from the 1980s. Integrated...
September 2016 - It can be obtained from Mouser Electronics the FAN602 integrated circuit...
This circuit was found in the component's own manual, which is not very common nowadays. Note that...