| 摘要 |
<p>An envelope is detected from each of a plurality of reproduced video FM signals successively read out from a magnetic tape, and a shape change of the envelope in one vertical scanning period is detected in a control microcomputer. In cases where the shape of the envelope is flattened, the flatness indicates that an inclination angle of a rotational drum is appropriately set and a scanning locus of a magnetic head attached on the rotational drum agrees with a track formed on the magnetic tape. In this case, a reproduced image having no noise is obtained. Therefore, the number of increase/decrease changes in the shape of the envelope is detected as a shape value. In cases where the shape value is high, the inclination angle of the rotational drum is largely and repeatedly changed until the shape value becomes low. In contrast, in cases where the shape value is low, the inclination angle of the rotational drum is slightly and repeatedly changed until the envelope shape is flattened. Accordingly, any noise does not occur in the reproduced image regardless of whether a magnetic recording and reproducing apparatus is used in interchangeable reproduction or self-recording/reproduction.</p> |
