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.
In the original 1992 application, this passive circuit was intended for use in the car. At that...
This 1995 circuit uses an audio amplifier that is no longer common today. However, other...
This circuit is from an 80's documentation. The integrated circuit is from the time and the...