This third-order Butterworth filter was found in American documentation from the 1980s. Formulas for component calculations are attached to the diagram.
This circuit was found in a Popular Electronics from the 90s. The circuit uses general purpose...
This circuit was found in an American publication from the 1970s. The circuit uses components from...
This 4-competitor TTL speed game was obtained in a 1980s documentation, but can still be easily...