This fader or fader was found in a 90s Popular Electronics. The circuit uses transistors that are equivalent to BC548. Input and output cables must be shielded.
Found in an American publication of 1968, this circuit makes use of a pilot light of the time. It...
This circuit was found in documentation from the 1980s requiring a variable power supply from 0 to...
This car alarm was found in an American '80s documentation. The circuit automatically activates...