Using a 709 integrated circuit this circuit was found in the June 1972 issue of Radio Electronics magazine. More modern operational equivalents can be used. The power supply is symmetrical.
This game was found in an old Popular Electronics. The unijunction transistor can be 2N2646. The...
This circuit interrupts the power supply when grounding is missing. The circuit is from an old...
In figure 1 we have a circuit that turns on after a certain time and then turns off, also after a...