Tracking control circuit
AssigneeSony Corporation
InventorsNorio Tanaka, Takato Narita
Life of this patent
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Abstract
A tracking control circuit for use in a composite digital video tape recorder, wherein the phase of a control signal is adjusted on the basis of a reproduced envelope signal in an interval of low correlativity to recorded contents out of the composite digital video signal reproduced by a recording head, so that the tracking position of the recording head relative to a video track is controlled to a predetermined proper position. In this circuit, accurate tracking control can be achieved at enhanced precision without enlarging the circuit scale or increasing the production cost.
Claims16
An improved tracking control circuit for precise tracking during edit mode operation of a recording device having a recording head, a playback head, and a capstan motor, and operable to play from and record on a magnetic tape, said circuit comprising:
- means for detecting the phase of a signal from said playback head;
- a detector, responsive to a signal from said record head, for reproducing an envelope signal indicative of recorded content on said magnetic tape;
- means, responsive to a timing signal, for sampling said envelope signal during a predetermined interval having low correlativity to said recorded content and producing a comparison signal therefrom;
- means, responsive to said phase signal and said comparison signal, for producing a control signal for controlling said capstan motor during edit mode of said recording device.
A method of controlling, during edit mode, the tracking of a recording device operable to play from and record on a magnetic tape having a video track thereon, said recording device having a recording head, a playback head, and a capstan motor, comprising the steps of:
- detecting the phase of a control signal reproduced from said playback head, for controlling said capstan motor;
- generating an envelope signal indicative of recorded video content on said magnetic tap using said recording head;
- sampling said envelope signal during a predetermined time interval having a low correlation with respect to said recorded video content to thereby produce a comparison signal;
- adjusting the phase of said control signal based on said comparison signal, whereby the tracking position of said recording head relative to a video track is controlled to a predetermined position.
Dependencies are inferred from the claim text.