| 摘要 |
<p>PURPOSE:To provide a magnetic recording and reproducing device capable of deciding the usable limit of a magnetic tape by detecting the deterioration rate of a running magnetic tape. CONSTITUTION:The tension of tape is measured by a pair of rotational posts 5, 5 provided at the back and forth of a fixed post 6 which is arranged in a running system of magnetic tape, and when a coefficient of friction of the magnetic tape 2 calculated from the ratio of these tape tensions exceeds the usable limit value set in advance, an alarm for this state is issued, thereby the usable limit of the aforementioned magnetic tape 2 is notified. The serious accidents such as a stop of magnetic tape running, etc., can be prevented beforehand, and also the time to replace the magnetic tape can be known.</p> |
