| 摘要 |
<p>PURPOSE:To eliminate a fixed head and to perform information reproduction of high quality and stable tracking control by detecting the reproduction level difference between pilot signals at 2nd parts of two tracks adjoining to 1st parts. CONSTITUTION:In a scanning period of a magnetic head, a pilot signal f2 is outputted from a pilot selecting circuit 37, and a frequency converting circuit 31 converts the frequencies of reproduction pilot signals of the main and both the adjacent tracks with the signal f2 and then outputs components of f0-f2 and f1-f2. A filter 32 extracts only f1-f2 from those two components and a detecting circuit 33 performs envelope detection. The circuit 22 detect only signals based upon the pilot signals f1 from both the adjacent tracks and its output includes a crosstalk component from both the adjacent tracks and is proportional in its output levels (x) and (y) to the tracking error quantity. For the purpose, those detection levels (x) and (y) are compared to detect the tracking error quantity and the polarity of the deviation.</p> |
