| 摘要 |
PURPOSE:To accurately estimate the degree of deterioration of a magnetic recording medium by securing a recording section following to a header section as a reading and writing frequency recording area and advancing the content of the recording area step by step at every reading out or writing operation. CONSTITUTION:A detect signal DP is commonly supplied to one of each AND input of FFs F1-F3 and, as a result of such connection, count data CD composed of each set output A, B, and C of the FFs F1, F2, and F3 are increased by one in response to the detect signal DP. The data CD are supplied to a writing circuit WC through a switch MW and written in the same header section as that, from which reading out data RD are read out and the header section in which 58 is initially recorded is updated to 68. Since this update is performed whenever a BOT detecting circuit DC detects a BOT mark, the header section records the summed result of the reading out or writing frequency of a magnetic tape. Therefore, the degree of deterioration of a magnetic recording medium can be estimated accurately. |
