This circuit that draws 1 out of 8 LEDs was found in an 80's American documentation. The circuit can also work with an astable using the 555 instead of the 4046 which is not a common component today.
This alarm oscillator was found in the December 1974 issue of Radio Electronics magazine. The...
In the figure we give the set-reset flip-flop configuration in which two Norton amplifiers are used in...
In this very simple circuit, the LED flashes at a frequency of 60 Hz. It is convenient to check the...