This game was found in Radio Electronics from the 90s. The components used are common except some that are from that time and that can no longer be found easily.
The purpose of this simple configuration, found in old documentation, is to trigger a buzzer if...
The sensor of this circuit is a large surface diode. We believe that a small solar cell can also...
This 3V-only circuit was found in old American documentation, but can be implemented with...