The circuit is from 1968, but we can use a modern one like the 741. The symmetrical power supply voltage (two batteries or source) can be from 9 to 12 V.
We found this circuit in a 70s American documentation. The integrated circuits are from that time....
The integrated circuit used in this regulator is unusual, as are the transistors. The circuit is...
This circuit was found in an old Radio Electronics, but can still be assembled as the components are...