Found in an Electronic Design of the 90's, this circuit provides an additional 12 V output to a 5 V regulator. The maximum current is 200 mA.
Old phones with dials can be used in a simple home intercom system, as this circuit from Popular...
This circuit was found in the July 1992 issue of Radio Electronics magazine. The circuit has a...
This simple circuit indicates if the polarity of a load is reversed when it is connected to a...