We found this circuit in the Radio Electronics magazine of December 1972. It generates signals in 6 frequency bands, being indicated for experimental applications with TTL circuits.
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...