We found this preamplifier for the 10 and 11-meter range in an old documentation for radio amateurs. The integrated circuit used is uncommon today.
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...