This circuit is from a documentation from the 70s. The circuit uses logic gates of the time, which in many cases were arrays of transistors allowing use as audio amplifiers, as in this case.
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...