This timer, like the previous circuits, uses a currently uncommon integrated circuit. The time is given by capacitor C1 and R2 which has the range of values indicated in the diagram.
We can assemble this circuit from a 1988 publication using more modern transistors. Thus, for Q1...
This circuit was found in an American documentation from 1966. The transistors are from that time...
This circuit was obtained in the publication 101 Electronics Projects of 1979. The circuit can be...