Magnetic tape apparatus

Claim 1

MAGNETIC TAPE APPARATUS COMPRISING, IN COMBINATION: A MAGNETIC TAPE CARRYING IN STACKES EXTENDING TRANSVERSELY THEREOF A MAGNETIC RECORD OF A FREQUENCY-MODULATED SIGNAL HAVING A PREDETERMINED MODULATION RANGE; DRIVE MEANS FOR TRAVERSING SAID TAPE THROUGH A REPRODUCING POSION; A ROATATING MEMBER AT SAID REPRODUCING POSITION CARRYING A PLURALITY TRANSDUCER HEADS; GUIDE MEANS AT SAID REPRODUCING POSITION CONSTRAINING SAID TAPE TO EMBRACE SAID MEMBER WHEREBY SAID TRANSDUCER HEADS ENGAGE SAID RECORDS TRACKS IN SUCCESSION TO REPRODUCE SAID SIGNAL THEREFROM; AN OUTPUT TERMINAL; A PLURALITY OF GATING MEANS EACH OPERABLE TO CONNECT A RESPECTIVE ONE OF SAID TRANSDUCER HEADS TO SAID OUTPUT TERMINAL; A SIGNAL GENERATOR YIELDING A STANDARD SIGNAL HAVING A FREQUENCY WITHIN SAID MODULATION RANGE, FURTHER GATING MEANS OPERABLE TO CONNECT SAID SIGNAL GENERATOR TO SAID OUTPUT TERMINAL, AND GATE CONTROL MEANS OPERATING SAID GATING MEANS TO CAUSE SAID STANDARD SIGNAL TO BE CONNECTED TO SAID OUTPUT TERMINAL IN PLACE OF SAID REPRODUCED SIGNAL DURING A PORTION OF THE PERIOD IN WHICH EACH AND TRANSDUCER HEAD IS OPERATIVE.