Abstract: An electronic integrator employing an algebraically summing operational amplifier which accepts input signals of opposite polarities, relative to a reference voltage, and wherein wind-up is alleviated by diodes which are normally reverse-biased and non-conductive but which respectively become conductive to clamp the net input voltage to a positive or negative magnitude which precludes further "wind-up" of the integrator output.

Abstract: Method and apparatus by which continuously existing analog voltage command signals for various channels within a control system are changed by determined amounts and senses as a result of supplying "pulse" signals of different durations and polarities. Electronic integrators preferably operating to create linear slope changes in their outputs, and to hold their outputs steady absent any input, are receptive to the change signals ("pulses") of differing durations to create analog command signals which change by increments proportional to the time duration and in a direction corresponding to the polarity of the change signal. This permits computer control of servo devices requiring continuously-existing, changeable command signals in the same fashion as servo devices which respond directly to variable duration, pulse-type change signals.