Found in a Popular Elecronics from the 90s, this circuit appears in other versions in this section and on the website. The circuit draws one of 10 LEDs and has a sound effect produced during the draw.
This diagram from a 1967 documentation shows how to switch high voltage neon lamps with 5V TTL...
This semi-proportional temperature control was found in old American documentation. The components are...
Found in a Popular Electronics from the 90s, this circuit makes use of an unusual integrated...