We found this circuit in the March 1995 issue of Electronics Now magazine. The circuit has a frequency range determined by C1 and R3. The signal generated is square.
Here we show how two 4017s can be cascaded to count above 10. The circuits are driven by a square...
The circuit in the figure represents a typical application of a phototransistor exciting a relay...
This circuit, in fact, what it does is a reactivation of the batteries through a brief pulsating...