Digital positional control system

Claim 1

A MOTOR CONTROL SYSTEM COMPRISING: A MOTOR; POSITION MEANS COUPLED TO SAID MOTOR YIELDING A PLURALITY OF DISTINCT DIGITAL SIGNALS FOR A CORRESPONDING PLURALITY OF POSITIONS OF SAID POSITION MEANS; A SINGLE POLARITY POWER SUPPLY; MEANS INCLUDING SAID POWER SUPPLY CONVERTING SAID CODED DIGITAL SIGNALS INTO A CORRESPONDING SERIES OF ELECTRICAL SIGNALS ALL OF THE SAME POLARITY; MOTOR CONTROL MEANS INCLUDING AN AMPLIFIER FOR CONTROLLING ENERGIZATION OF SAID MOTOR; COMMAND SIGNAL MEANS SELECTIVELY YIELDING A SERIES OF DISTINCT CODED ELECTRICAL SIGNALS FOR EACH DESIRED ONE OF SAID POSITIONS OF SAID POSITION MEANS, SAID LAST MENTIONED ELECTRICAL SIGNALS ALSO ALL BEING OF SAID POLARITY; COMPARING MEANS COMPARING SAID TWO SERIES OF ELECTRICAL SIGNALS ON A DIGIT TO DIGIT BASIS AND PRODUCING ERROR SIGNALS HAVING SAID POLARITY BUT WHOSE MAGNITUDES ARE REPRESENTATIVE OF DIFFERENCES BETWEEN THE ACTUAL POSITION OF SAID POSITION MEANS AND THE POSITION CORRESPONDING TO THAT DICTATED BY SAID COMMOND SIGNAL MEANS; AND TRANSLATION MEANS COUPLED TO SAID MOTOR CONTROL MEANS FOR CONTROLLING OPERATION THEREOF IN ACCORDANCE WITH SAID ERROR SIGNALS, SAID TRANSLATION MEANS INCLUDING A TRANSISTOR AMPLIFIER HAVING A SERIES OF NULLING CIRCUITS IN ITS INPUT, SAID NULLING CIRCUITS SEQUENTIALLY DETECTING COINCIDENCE BETWEEN SAID TWO SERIES OF ELECTRICAL SIGNALS AS THE POSITION OF SAID POSITION MEANS APPROACHES THE POSITION DICTATED BY SAID COMMAND SIGNAL MEANS.