Image Number 7 for United States Patent #4587581.
Tracking control apparatus for a magnetic storage device is provided for playback of information recorded on tracks at alternating azimuth angles which correspond to mutually different azimuth angles of a pair of magnetic playback heads. The playback heads have track-wise widths which are less than the width of their associated record tracks, to prevent the attenuation of their playback signals resulting from limited playback head tracking error. A tracking control head, which has an azimuth angle of one of the playback heads, is mounted for selectively overlapping adjacent record tracks in accordance with the magnitude and direction of the tracking error of the playback heads. Signal comparison circuitry produces a tracking error signal in accordance with the difference between the output of the control head and the output of a playback head. When the storage device is magnetic tape having information recorded on slant tracks, a tape drive servomechanism, responsive to the error signal, momentarily adjusts the speed of the tape, to align the playback heads with respect to their associated record tracks.