Automatic frequency control system for high frequency transmitters

Claim 1

IN A WAVE GENERATING SYSTEM HAVING MEANS FOR PRODUCING HIGH FREQUENCY ELECTROMAGNETIC OSCILLATIONS, AN AUTOMATIC FREQUENCY CONTROL SYSTEM INCLUDING IN COMBINATION, A CAVITY RESONATOR CONTAINING A FERRITE MATERIAL FOR SUSTAINING OSCILLATIONS, MEANS FOR COUPLING A PORTION OF THE GENERATED WAVE TO SAID RESONATOR, MEANS FOR APPLYING A MAGNETIC FIELD TO THE FERRITE MATERIAL IN SAID RESONATOR, SAID MAGNETIC FIELD HAVING A UNIDIRECTIONAL COMPONENT FOR ESTABLISHING THE RESONANT FREQUENCY OF SAID RESONATOR AND AN ALTERNATING COMPONENT FOR PRODUCING FREQUENCY DEVIATION ABOUT SAID RESONANT FREQUENCY, SAID UNIDIRECTIONAL COMPONENT BEING APPLIED INDEPENDENTLY OF SAID ALTERNATING COMPONENT AND BEING LARGE WITH RESPECT TO SAID ALTERNATING COMPONENT SUCH THAT SAID RESONATOR IS TUNABLE BY SAID UNIDIRECTIONAL COMPONENT IN THE ABSENCE OF SAID ALTERNATING COMPONENT, DETECTOR MEANS COUPLED TO SAID RESONATOR TO PROVIDE A SIGNAL HAVING AMPLITUDE MODULATIONS INDICATIVE OF THE FREQUENCY DEVIATIONS PRODUCED BY SAID ALTERNATING MAGNETIC FIELD COMPONENT, AND MEANS RESPONSIVE TO SAID DETECTED SIGNAL TO CONTROL THE FREQUENCY OF OSCILLATIONS PRODUCED BY SAID WAVE GENERATING SYSTEM, WHEREBY SAID RESONATOR MAY BE PRETUNED IN THE ABSENCE OF THE ALTERNATING COMPONENT OF SAID MAGNETIC FIELD, THEREBY TO FUNCTION AS AN AUTOMATIC FREQUENCY CONTROL REFERENCE AND A FREQUENCY MONITOR IN SAID SYSTEM.