Found in a 1968 Ferranti documentation, this circuit can be implemented with modern equivalent semiconductors. With the indicated components the load can be a lamp up to 1 A.
When more current from a digital output is needed than a single output could source or drain, a...
Using a small speaker as a microphone, this 10-LED circuit was found in the March 1992 issue of...
This is an integrated recommended for portable amplifiers, recorders, and battery powered radios. It...