Found in American documentation from the 90s, this circuit can be applied to other operational ones. We found it in an EDN of the time. Next to the diagram is the response curve.
Found in an English publication from 1977, this circuit uses only 1 LED. Unlit means heads and lit...
The purpose of this interesting circuit found in a 1977 documentation is to complete the last...
The 709 integrated circuit is not common today. The circuit is from American technical...