Found in an old Elektor, this circuit uses two 7-segment displays to indicate the volume of an amplifier. The circuit uses components that are still common today.
We found this speed control for miniature cars in an American publication from the 70s. With...
The sample and hold circuit used in analog to digital converters shown below was found in the...
This circuit was found in an English magazine from 1978, but it is still current, just change the...