This circuit has an interface for a multimeter or electronic voltmeter. We found it in a 90s Electronic Engineering. The sensor is an unusual component today.
This two-transistor MW radio was found in a publication from 1958. It uses one of the oldest type...
Found in a 1988s Radio Electronics, this circuit uses transistors of general use to increase the...
This circuit can be applied to other 3-terminal regulators and equivalent transistors can be used....