Random access instantaneous digital-to-analog co-ordinate converter

Claim 1

A RANDOM ACCESS DIGITIAL-TO-ANALOG INSTANTANEOUS COORDINATE CONVERTER COMPRISING: TWO PAIRS OF DIGITIAL-TO-ANALOG CONVERTERS, EACH CONVERTER HAVING TWO INPUTS AND AN OUTPUT, THE FIRST PAIR OF CONVERTERS EACH HAVING A FIXED REFERENCE VOLTAGE COUPLED TO ONE INPUT THEREOF AND THE SECOND PAIR OF CONVERTERS EACH HAVING ONE OF THE INPUTS THEREOF COUPLED TO THE OUTPUTS OF SAID FIRST PAIR OF CONVERTERS, RESPECTIVELY; A DIGITAL WORK, RESPRESENTATIVE TO THE SIN O FUNCTION OF A TARGET PORITION WITH RESPECT TO A POINT OF OBSERVATION, APPLIED TO THE SECOND INPUT OF ONE OF SAID CONVERTERS OF SAID FIRST PAIR OF CONVERTERS TO PRODUCE AN ANALOG VOLTAGE CORRESPONDING TO SAID SIN O FUNCTION ON THE OUTPUT OF SAID ONE CONVERTER; A DIGITAL WORD, REPRESENTATIVE OF THE COS O FUNCTION OF THE TARGET POSITION WITH RESPECT TO THE POINT OF OBSERVATION, APPLIED TO THE SECOND INPUT OF THE OTHER OF SAID CONVERTERS OF SAID FIRST PAIR OF CONVERTERS TO PRODUCE AN ANALOG VOLTAGE CORRESPONDING TO SAID COS O FUNCTION ON THE OUTPUT OF SAID OTHER CONVERTER; AND A RANGE COUNTER FOR COUNTING OUT A DIGIT WORD, REPRESENTATIVE OF THE RANGE OF THE TARGET FROM THE POINT OF OBSERVATION, HAVING ITS DIGITAL WORD OUTPUT APPLIED TO THE SECOND INPUTS OF SAID SECOND PAIR OF CONVERTERS, IN COMMON, TO PRODUCE ANALOG VOLTAGES ON THE OUTPUTS OF SAID SECOND PAIR OF CONVERTERS OF THE RANGE AND SIN O FUNCTION AND OF RANGE AND COS O FUNCTION PROVIDING CO-ORDINATE VOLTAGES OF THE TARGET WITH RESPECT TO THE POINT OF OBSERVATION.