This circuit was found in a 90’s Popular Electronics. The circuit is used to analyze noise in vehicles. The output must be in a low impedance headset.
This circuit allows 220 / 240V shavers to be used in the 110V network. The diodes can be general...
Found in July 1975, Radio Electronics magazine this circuit can use any operating circuit,...
Here we have in the figure the configuration of the circuit as a conventional Darlington. In this...