Potentiometric circuit arrangement

A potentiometric circuit arrangement comprising a resistive element extending between two fixed terminals, a signal-tapping member movable along the resistive element to derive a signal from the resistive element, integration means operable to integrate with respect to an integration datum a signal derived from the signal-tapping member and provide an integrated signal and feedback means including means, including a source of reference voltage of amplitude in excess of the maximum integrated signal amplitude and algebraic summing means, operable to apply to one of said fixed terminals a voltage related to the amplitude of the reference voltage reduced by the amplitude of the integrated signal and means operable to apply to the other of said fixed terminals a voltage related to the amplitude of the integrated signal but of opposite polarity, with respect to the integration datum, to the voltage applied to said one of the fixed terminals such that a voltage having a peak amplitude equal to the reference voltage exists between the fixed terminals and a null voltage, with respect to said integration datum, exists at some position between the fixed terminals, said integration means being responsive to variation of the input signal thereto by displacement of the signal-tapping member from said null voltage position towards either fixed contact to vary the amplitudes of the signals applied to the fixed terminals relative to each other to restore the null voltage to the position of signal-tapping member and to provide said integrated signal amplitude as a function of the position of the signal-tapping member with respect to the fixed terminals.