We found this circuit in an 80's EDN. The circuit makes use of a MAX680, being given a table with its operating characteristics.
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...