Abstract: A control system for the automatic adjustment of controlling elements. The ystem includes a pulse controlled servo follow-up circuit, a signal generating circuit, a sensing circuit, a system controller and a switching circuit. The system controller is either a special or small general purpose digital device which transmits a control signal to the switching circuit in response to the output of the sensing circuit. The switching circuit provides either of two variable time duration pulse control signals to the pulse-controlled follow-up circuit. One control signal will cause the follow-up circuit to provide a positive control and the other control signal will cause negative control. The amount of positive or negative control is determined by the time duration of the pulse. The signal generating device will be controlled by the output of the follow-up circuit and the sensing circuit will measure the condition of the signal generating circuit.