This circuit with the NE602 was found in the February 1997 Electronics Now magazine. The NE602 integrated circuit is not very common these days.
Here we have an interesting circuit found in a 1981 publication that causes two LEDs to flash...
This circuit was found in Delco documentation from 1965. The transistor is of the time, but any...
This circuit transmits signals to an FM receiver at a distance of up to a few tens of meters. The...