This circuit, for frequencies up to 100 kHz, was found in American documentation from 1970. The circuit can serve as a reference for projects with modern equivalent components.
This circuit is from an old documentation of Radio Shack from the 70s. The transistor should...
This circuit allows the use of a milliammeter in the measurement of low frequency alternating...
This circuit was found in a 1966 General Electric documentation. It makes use of direct contact...