Found in the February 1983 Radio Electronics magazine, this circuit uses a FET and has good gain at the frequencies determined by the components. The FET is any general-purpose FET.
This circuit is from 1998 documentation. The circuit uses the TDA2002 in a bridged configuration and...
April 2017 - Mouser Electronics is making available this new component for open LED protection...
This tri-state comparator was found in a circuit manual from the 1980s, but it can be easily...