| 摘要 |
PROBLEM TO BE SOLVED: To increase the amount of information by repairing data at a detected defect place according to other read data and extracting data of a data series. SOLUTION: Data from the conveyance start end side of a track are read in sequence and stored in the memory of a data processing circuit and the conveyance distance from the conveyance start end side begins to be measured. When the data read reaches the 2nd bit of data D2, no signal is present, it is decided that data at the place is absent, and the conveyance distance (t) of the place is stored in the memory of the data processing circuit. Then the data at the absence place are repaired. Repairing is carried out by a known method using an error correction code. The data processing circuit takes a specific data analysis such as a decision on whether, for example, track data are true or false according to the distance up to the measured data defect place to take an analysis according to data D1 to D3 read out of the track. |
