Found elsewhere in this section, but from other sources, this circuit is from Motorola documentation. The circuit uses a triac of the time and a tripping transformer. The circuit is for 110 V network.
We found this circuit in a 1968 Electronics World. The transistors are from the era and...
There are several manufacturers of the integrated circuit used and it also admits equivalents. The circuit...
This circuit is from 1971 American documentation. Transistors are still common except for 2N2060...