The integrated circuit used in this regulator is not common today. The circuit is from a technical documentation from the 80's and is only used as a reference for eventual repair.
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...