Apparatus for producing a replica of repetitive waveforms having undesired voltages superimposed thereon

Claim 1

APPARATUS FOR PRODUCING A REPLICA OF AT LEAST A PORTION OF A RECURRING WAVEFORM THAT CHANGES AMPLITUDE IN A PERIODICAL MANNER AT A FREQUENCY GREATER THAN A PREDETERMINED VALUE AND HAS SUPERIMPOSED THEREON AN UNDESIRED VOLTAGE THAT DOES NOT CHANGE AMPLITDUE WITH SAID WAVEFORM, SAID APPARATUS COMPRISING, MEANS FOR SAMPLING EACH OF SAID RECURRENT WAVEFORMS WITH SAMPLES TAKEN AT LATER TIMES IN SUCCESSIVE ONES OF SAID WAVEFORMS AND PRODUCING EACH OF SAID SAMPLES AS AN OUTPUT UNTIL THE NEXT OF SAID SAMPLES IS TAKEN, SAID LATER TIMES IN SAID SUCCESSIVE WAVEFORMS INCREASING AT TIME INTERVALS THAT CAUSE SAID SAMPLING MEANS OUTPUT ATTRIBUTABLE TO SAID UNDERSIRED VOLTAGES TO HAVE A MAXIMUM FREQUENCY LESS THAN SAID PREDETERMINED VALUE, HIGH PASS FILTER MEANS CONNECTED TO SAID SAMPLING MEANS AND HAVING A CUT-OFF FREQUENCY AT SUBSTANTIALLY SAID PREDETERMINED VALUE, WAVE AMPLITUDE DETECTING MEANS CONNECTED TO SAID HIGH PASS FILTER MEANS, AND UTILIZATION MEANS CONNECTED TO SAID WAVE AMPLITUDE DETECTING MEANS.