Found in the March 1989 issue of Radio Electronics magazine, this circuit is used to test printer and other cables. The indication is made by LEDs.
This circuit uses a 7812 and another regulator integrated circuit that is not very common...
The project is from a 1992 publication, but totally current by the components it uses. The LEDs...
We have a simple and useful circuit found in a 1982 documentation which generates a signal in the...