This interesting circuit in which the LED display is circular imitating a common clock appeared in the Radio Electronics magazine of May 1977. The power supply is included.
We found this circuit on the internet. The components are current, and the time depends on C1...
This circuit was found in an English publication of 1982. The operational can be replaced by an...
With this luminous remote control, which we found in a 1990 publication, using a flashlight you...