Transistor servo system

Claim 1

IN A SERVO SYSTEM, THE COMBINATION COMPRISING: AN ERROR POTENTIOMETER AND A REBALANCING POTENTIOMETER, EACH CONNECTED ACROSS A SOURCE OF DIRECT CURRENT, SAID ERROR POTENTIOMETER INCLUDING A FIRST MOVABLE CONDUCTIVE TAP AND SAID REBALANCING POTENTIOMETER INCLUDING A SECOND MOVABLE CONDUCTIVE TAP; A WIDEBAND AMPLIFIER OPERATIVELY BIASED BY SAID SOURCE AND HAVING AN INPUT CIRCUIT AND AN OUTPUT CIRCUIT, SAID INPUT CIRCUIT BEING CONNECTED ACROSS SAID TAPS; A REVERSIBLE DIRECT CURRENT MOTOR CONNECTED IN THE OUTPUT CIRCUIT OF SAID AMPLIFIER, SAID OUTPUT CIRCUIT INCLUDING MEANS FOR ENERGIZING SAID MOTOR FROM SAID SOURCE IN ONE DIRECTION WHEN THE VOLTAGE AT SAID FIRST TAP INCREASES WITH RESPECT TO THE VOLTAGE AT SAID SECOND TAP, AND FROM SAID SOURCE IN THE OPPOSITE DIRECTION WHEN THE VOLTAGE AT SAID FIRST TAP DECREASES WITH RESPECT TO THE VOLTAGE AT SAID SECOND TAP; A NEGATIVE FEEDBACK CONNECTION FROM SAID MOTOR TO SAID INPUT CIRCUIT, SAID CONNECTION COMPRISING A MECHANICAL COUPLING BETWEEN THE SHAFT OF SAID MOTOR AND SAID SECOND TAP; AND A REGENERATIVE FEEDBACK CONNECTION FROM SAID OUTPUT CIRCUIT TO SAID INPUT CIRCUIT WHEREBY OSCILLATIONS ARE SET UP IN SAID AMPLIFIER, SAID OSCILLATIONS HAVING A FREQUENCY AND AMPLITUDE DEPENDENT ON THE MAGNITUDE OF VOLTAGE DIFFERENCE BETWEEN SAID FIRST AND SECOND TAPS.