| 摘要 |
The present invention is intended for use in a signal reproducing system of the type having at least one rotary transducer for scanning traces across a movable record medium, such as a magnetic tape, to reproduce signals from previously recorded record tracks. Each transducer is supported on a displaceable support member that is responsive to control signals to displace the transducer relative to the record tracks. The record medium is movable at a speed which may be less than, equal to or greater than the speed at which the signals originally were recorded. A frequency generator generates speed representing pulses whose frequency is a function of the speed at which the record medium is moved. A cyclical, or resettable, counter cyclically counts the speed representing pulses. A level generator generates a signal level corresponding to the count then present in the counter at the time that a transducer advances to the middle portion of a scanning trace. The generated signal level is used as a control signal to correspondingly displace the transducer support member. This displacement provides general compensation for the deviation between the scanning trace of the transducer and the record track which is scanned thereby. In a preferred use of the present invention, the signal reproducing system is a VTR, and tracking compensation is provided for slow or fast modes of reproduction. In accordance with another feature, a sawtooth signal having a period equal to a head scanning period, and an amplitude determined by the speed at which the record medium (or tape) is moved is added to the generated level in order to provide substantially continuous error correction of the head scanning trace.
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