This circuit that uses potentiometer tuning, was found in a documentation from the 80's. The integrated circuit used is from that time and is a not common today.
In this application we use an additional input circuit to enable logical command with switches, sensors...
This is one of the first games that came out in the 70s. This one is from a Radio Electronics...
The figure shows how to control the counting of a 4017 with a start and stop switch. | Clique na...