We found this circuit in a Popular Electronics from the 80s. It is a game of reaction speed for 3 competitors. Indicator LEDs are used.
This circuit was found in ancient American documentation. Diodes are general-purpose types. |...
This 80's General Electric circuit is guarded by the noise-guard for operating current. The...
This circuit was found in the January 1975 Radio Electronics magazine. The diodes are current...