Frequency comparing systems

Claim 1

A FREQUENCY COMPARISON SYSTEM CAPABLE OF COMPARING A SIGNAL FREQUENCY WITH A REFERENCE FREQUENCY COMPRISING COMMUTATING MEANS ARRANGED IN USE TO COMMUTATE THE SIGNAL FREQUENCY WITH THE REFERENCE FREQUENCY SO AS TO PRODUCE A RESULTANT WAVEFROM CONSISTING OF ALTERNATE ELEMENTS OF THE SIGNAL FREQUENCY AND REFERENCE FREQUENCY WHEREIN EACH ELEMENT COMPRISES A NUMBER OF CYCLES OF THE REFERENCE FREQUENCY OR THE SIGNAL FREQUENCY AS THE CASE MAY BE, COUNTER MEANS ARRANGED IN USE TO COUNT A PREDETERMINED NUMBER OF CYCLES OF EACH ELEMENT OF THE RESULTANT WAVEFORM SO AS TO PRODUCE FOR EACH ELEMENT A CORRESPONDING OUTPUT PULSE WHOSE DURATION IS CHARACTERISTIC OF THE FREQUENCY OF THE ELEMENT TO WHICH IT CORRESPONDS, SUCCESSIVE OUTPUT PULSES BEING ALTERNATELY CHARACTERISTIC OF THE REFERENCE FREQUENCY AND THE SIGNAL FREQUENCY, CONVERTER MEANS FED WITH THE OUTPUT PULSES FROM THE COUNTER SO AS TO PRODUCE CORRESPONDING PULSES THE AMPLITUDE OF ALTERNATE ONES OF WHICH ARE CHARACTERISTIC OF THE REFERENCE FREQUENCY AND THE SIGNAL FREQUENCY RESPECTIVELY, SAMPLING MEANS ARRANGED SO AS TO SAMPLE THE AMPLITUDE OF EACH SUCCESSIVE CORRESPONDING PULSE, AND CAPACITOR MEANS ARRANGED SO AS TO BE CHARGED OR PARTIALLY DISCHARGED BY SAID CORRESPONDING PULSES DEPENDENT UPON THEIR SAMPLE AMPLITUDE SO AS TO PRODUCE AN OUTPUT SIGNAL CHARACTERISTIC OF THE FREQUENCY DIFFERENCE BETWEEN THE SIGNAL FREQUENCY AND THE REFERENCE FREQUENCY.