In the figure we have one of the many ways to program the counting of a 4017. The circuit uses additional gates and was found in the Radio Electronics magazine of April 1989.
This circuit appears in several versions in publications of the time and can be modified by...
This interesting circuit of the American publication Electronics Handbook Volume XIII 1993 shows a...
This simple SCR alarm circuit was found in an old Poptronics, but can be easily assembled as all...