| 摘要 |
<p>PURPOSE:To achieve a detecting operation surely with a simple constitution, by directly giving a light to a write permission ring loading section of a tape reel and detecting the presence and the absence of the reflecting light in a magnetic tape recorder/reproducer for electronic computer. CONSTITUTION:In a magnetic tape recorder/reproducer for electronic computer, a write permission ring 22 is loaded in a groove 21a formed as a write permission ring loading section at hub side surface of a tape reel 21 and a light emitting 23 and a photodetector 24 are provided with a slope so that a light can directly touch on the loading section of the ring 22. That is, in the loading state of the write permission ring 22, the light from the light emitting element 23 is reflected at the external circumference of the ring 22, the reflected light is received at the photodetector 24 and a write permission instruction is given to a photodetection circuit.</p> |
