Suggested by Maxim in documentation from the 90s, this circuit has its response curve given next to the diagram as well as the formulas for the component calculations.
The circuit shown is from an old European publication. In it we have the way to activate a relay...
We found this circuit in a European publication from the 1990s. Transistors are still common types...
This circuit was found in an American documentation and can be added to common amplifiers of any...