Found in a Popular Electronics from the 90s, this game can be seen in other configurations on this site. The circuit uses components that are still common today.
This different configuration for a crystal galena radio or modernized since a diode is used, has a...
This circuit is from 1990 documentation. When we press D1 the lamp remains on for a time interval that...
This version of the test lights a lamp when the ring touches the tortuous wire. The SCR can be the...