Telemetering system

Claim 1

A TELERMETERING SYSTEM COMPRISING A TRANSMITTER AND A RECEIVER, SAID TRANSMITTER INCLUDING CHOPPING MEANS FOR CONVERTING AN INPUT ANALOG VOLTAGE TO A FIRST FUNCTIONALLY RELATED FREQUENCY, HIGH GAIN ALTERNATING CURRENT AMPLIFYING MEANS FOR RECEIVING SAID FIRST FUNCTIONALLY RELATED FREQUENCY FROM SAID CHOPPING MEANS IN ORDER TO PRODUCE AN AMPLIFIED SIGNAL, SYNCHRONOUS DEMODULATING MEANS FOR RECEIVING SAID AMPLIFIED SIGNAL FROM SAID HIGH GAIN ALTERNATING CURRENT AMPLIFYING MEANS TO PRODUCE A FIRST FUNCTIONALLY RELATED VOLTAGE, OSCILLATING MEANS FOR APPLYING FUNCTIONALLY RELATED OSCILLATING SIGNALS TO SAID CHOPPING MEANS AND SAID SYNCHRONOUS DEMODULATING MEANS, VOLTAGE TO FREQUENCY TRANSLATING MEANS FOR RECEIVING SAID FIRST FUNCTIONALLY RELATED VOLTAGE FROM SAID SYNCHRONOUS DEMODULATING MEANS AND FOR PRODUCING A SECOND FUNCTIONALLY RELATED FREQUENCY, TRANSMITTING OUTPUT MEANS FOR DIRECTING SAID SECOND FUNCTIONALLY RELATED FREQUENCY THROUGH A TRANSMISSION MEDIUM, FIRST FREQUENCY TO VOLTAGE TRANSLATING MEANS FOR RECEIVING SAID SECOND FUNCTIONALLY RELATED FREQUENCY AND PRODUCING A FEEDBACK SIGNAL, FIRST REFERENCE COMPARATOR MEANS FOR COMPARING A REFERENCE SIGNAL WITH SAID FEEDBACK SIGNAL AND FOR APPLYING A RESULTING CONTROL SIGNAL TO SAID CHOPPING MEANS, SAID FIRST FREQUENCY TO VOLTAGE TRANSLATING MEANS HAVING A TRANSFORMER WITH A CORE CHARACTERIZED BY A SUBSTANTIALLY SQUARE HYSTERESIS LOOP BY WHICH ITS OPERATION IS SUBSTANTIALLY UNAFFECTED BY ENVIRONMENTAL CONDITIONS, SAID RECEIVER INCLUDING SECOND FREQUENCY TO VOLTAGE TRANSLATING MEANS FOR RECEIVING SAID SECOND FUNCTIONALLY RELATED FREQUENCY THROUGH SAID TRANSMISSION MEDIUM AND FOR PRODUCING A PRELIMINARY OUTPUT SIGNAL, SAID SECOND FREQUENCY TO VOLTAGE TRANSLATING MEANS HAVING A TRANSFORMER WITH A CORE CHARACTERIZED BY A SUBSTANTIALLY SQUARE HYSTERESIS LOOP BY WHICH ITS OPERATION IS SUBSTANTIALLY UNAFFECTED BY ENVIRONMENTAL CONDITIOUS SECOND REFERENCE COMPARATOR MEANS FOR COMPARING A REFERENCE SIGNAL WITH SAID PRELIMINARY OUTPUT SIGNAL IN ORDER TO PRODUCE A FINAL OUTPUT SIGNAL FOR APPLICATION TO AN INDICATOR, SAID FIRST FREQUENCY TO VOLTAGE TRANSLATING MEANS AND SAID FIRST REFERENCE COMPARATOR MEANS BEING MATCHED WITH SAID SECOND FREQUENCY TO VOLTAGE TRANSLATING MEANS AND SAID SECOND REFERENCE COMPARATOR MEANS IN ORDER TO ACHIEVE INHERENT SIMILARITY BETWEEN ANALOGOUS SIGNALS CONTROLLED THEREBY, EACH OF SAID FIRST REFERENCE COMPARATOR MEANS AND SAID SECOND REFERENCE COMPARATOR MEANS BEING CHARACTERIZED BY A ZENER DIODE WHICH PROVIDE A PRECISE COMPARISON SIGNAL, THE ZENER DIODE OF THE FIRST REFERENCE COMPARATOR MEANS AND THE ZENER DIODE OF SAID SECOND REFERENCE CHARACTER MEANS BEING SUBSTANTIALLY ALIKE, EACH OF SAID FIRST FREQUENCY TO VOLTAGE TRANSLATING MEANS AND SAID SECOND FREQUENCY TO VOLTAGE TRANSLATING MEANS INCLUDING A NON-CRITICAL PASSIVE NETWORK OF RESISTORS AND CAPACITORS, THE LINEARITY OF RESPONSE OF SAID FIRST FREQUENCY TO VOLTAGE TRANSLATING MEANS AND THE LINEARITY OF RESPONSE OF SAID SECOND FREQUENCY TO VOLTAGE TRANSLATING MEANS BEING IRRELEVANT BECAUSE OF MATCHING WHICH EXACTLY COMPENSATES FOR ANY NON-LINEARITY PRESENT.