Found in an Electronics World of 1966 this circuit can be made with current power transistors. It causes colored lamps to flash to the rhythm of the audio signal applied to the input.
The integrated circuits in this application are not very common today. One consists of an A / D...
This CMOS oscillator circuit generates signals up to a few megahertz, depending on the capacitor value....
This circuit was found in a 1977 American manual. The integrated circuit is from the time....