Multistage frequency measurement system utilizing predetermined frequency slip factors

Claim 1

THE FREQUENCY MEASURING SYSTEM, COMPRISING A PLURALITY OF DECREMENTAL FREQUENCY SUBTRACTIVE STAGES EACH STAGE INCLUDING A SOURCE OF FIXED REFERENCE FREQUENCY, A HARMONIC SELECTOR FOR EACH STAGE TO SELECT A PARTICULAR HARMONIC OF THE FIXED FREQUENCY FOR THAT STAGE WHICH HARMONIC CAN BE ANY ONE OF TEN HARMONICS OF THE FIXED REFERENCE FREQUENCY FOR THAT STAGE, A TUNABLE RESONANT CIRCUIT FOR EACH STAGE, MEANS TO APPLY AN UNKNOWN FREQUENCY TO THE INPUT OF THE TUNED RESONANT CIRCUIT TO SAID FIRST STAGE, MEANS TO TUNE SAID RESONANT CIRCUIT TO SAID UNKNOWN FREQUENCY AND TO PRODUCE A RESONANCE INDICATION, MEANS TO ADJUST SAID HARMONIC SELECTOR TO SELECT THE PARTICULAR ONE OF SAID TEN HARMONICS HAVING A PREDETERMINED FREQUENCY SLIP FACTOR OF NOT LESS THAN TWO WITH RESPECT TO THE TUNED FREQUENCY OUTPUT OF SAID RESONANT CIRCUIT, MIXER MEANS FOR MIXING SAID SELECTED HARMONIC WITH SAID TUNED OUTPUT, MEANS TO APPLY THE DIFFERENCE FREQUENCY BETWEEN SAID SELECTED HARMONIC AND THE TUNED OUTPUT OF THE RESONANT CIRCUIT OF THE FIRST STAGE TO THE INPUT OF THE TUNABLE RESONANT CIRCUIT OF THE NEXT STAGE, AND MEANS TO ADJUST THE HARMONIC SELECTOR OF SAID NEXT STAGE TO SELECT THE PARTICULAR ONE OF THE TEN HARMONICS THEREOF HAVING A PREDETERMINED FREQUENCY SLIP FACTOR OF NOT LESS THAN TWO WITH RESPECT TO THE FREQUENCY OF THE TUNED RESONANT CIRCUIT OF SAID NEXT STAGE WHEREBY FREQUENCY INVERSION BETWEEN SUCCESSIVE STAGES IS AVOIDED.