This rapid response amplifier uses an integrated one that is not common today but can be implemented with modern equivalents. The circuit is from an 80's manufacturer documentation.
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...