Electrocardiographic means

Claim 1

APPARATUS FOR VISUALLY DISPLAYING WAVEFORMS OF SIGNALS MAGNETICALLY RECORDED ON A TAPE, SAID APPARATUS INCLUDING THE COMBINATION OF: A FIRST PLAYBACK HEAD FOR SCANNING A TRACK ON SAID TAPE CONTAINING SAID MAGNETIC RECORDINGS AND PRODUCING TRIGGER SIGNALS IN RESPONSE TO SAID RECORDINGS, A SECOND PLAYBACK HEAD FOR SCANNING A TRACK CONTAINING SAID MAGNETIC RECORDINGS AND PRODUCING A SIGNAL IN RESPONSE THERETO, SAID HEADS BEING POSITIONED RELATIVE TO EACH OTHER SO THAT SAID TRIGGER SIGNALS OCCUR PREDETERMINED TIME INTERVALS BEFORE CORRESPONDING PORTIONS OF SAID SIGNALS FROM SAID SECOND HEAD, DISPLAY MEANS INTERCONNECED WITH SAID SECOND PLAYBACK HEAD TO RECEIVE THE SECOND REPRODUCED SIGNALS THEREFROM, SAID DISPLAY MEANS INCLUDING A DISPLAY AREA AND BEING RESPONSIVE TO THE SECOND REPRODUCED SIGNAL FROM SAID SECOND HEAD FOR PRODUCING VISUAL DISPLAYS OF THE WAVEFORMS ON SAID DISPLAY AREA, AND SWEEP MEANS IN SAID DISPLAY MEANS FOR SWEEPING ACROSS SAID DISPLAY AREA AND BEING INTERCONNECTED WITH SAID FIRST PLAYBACK HEAD FOR RECEIVING SAID TRIGGER SIGNALS, SAID SWEEP MEANS BEING RESPONSIVE TO THE TRIGGER SIGNALS FOR SYNCHRONIZING SAID DISPLAY MEANS IN RESPONSE TO SAID TRIGGER SIGNALS TO INITIATE A NEW SWEEP ACROSS SAID DISPLAY AREA TO PRODUCE A VISUAL DISPLAY OF THE SECOND REPRODUCED SIGNAL.