This simple circuit can work with either 4.5 V or 6 or 9 V if a 1k resistor is added in series with the set of LEDs. The circuit is from an old French publication.
This circuit was found in Intersil's 1992 documentation consisting of a test for ADc0801 and...
This 60's shield or driver employs germanium transistors. The circuit is from a 1960 Gernsback...
The circuit shown in the figure on the right can be used on a data transfer bus with the use of an...