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.
Using an operational that is not common today, but which admits a modern equivalent, we found this...
This simple source of up to 1 A can supply voltages according to the secondary of the transformer, in this...
This interference rejection circuit for telegraphy was found in a 1980s documentation for radio...