This circuit is from Ferranti documentation from 1967. The operational is of the time, but the configuration is valid for modern equivalent components, including higher current capacity.
Using LM3909 integrated circuits, this circuit was found in an American documentation from the...
This circuit was found in an ancient American documentation. The components of the time are not...
This circuit with low impedance output and 900k input impedance was found in the October 1993...