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.
We found this circuit in an English publication from 1980. The maximum output current depends on...
Found in an Elektor from the 90s, this TTL circuit can be used as a shield without any bouncing...
This circuit with a bargraph scale was found in a 90s Popular Electronics. The circuit measures...