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 was found in documentation from the 1980s. The transistor depends on the desired...
We found this circuit in a 1985 technical publication. The circuit uses PUTs to drive lamps....
This type of circuit, found in American documentation from the 1980s, triggers producing output...