Found in a Popular Electronics from the 90s, this circuit uses common components with several operational options, including the use of an optocoupler that allows its application in a shield.
The integrated circuit used is not common today. The circuit is from the SGS linear integrated circuits...
This circuit includes the power supply from the power grid. We found it in Radio Electronics from...
This circuit was found in the April 1998 issue of Electronics Now magazine. The circuit uses...