This circuit of starting lights for auto-race was found in an English documentation from the 80's. The LEDs must be of different colors, for greater realism.
This biestable circuit was found in a Popular Electronics from the 90s. The circuit has an unusual...
This 3-step circuit for generating digital signals was found in the November 1976 issue of Radio...
This circuit for low frequency signals from the Loran guidance system was discovered in the July...