This circuit was obtained from an Electronic Design of 1968. The circuit uses components of the time that can eventually be exchanged for current equivalents.
This is a typical source of the time (1989) using the well-known regulator integrated circuit 723....
Found in American documentation from 1964, this circuit uses transistors from that time, which are not...
In the circuit of the figure, we have an application different from 4093. The astable...