| 摘要 |
<p>PURPOSE:To display the tape position capable of being easily seen without a complicated configuration by positively feeding back the output of the comparator to one input side of this comparator and by connecting it to the output side of the delay circuit to make it ON or OFF. CONSTITUTION:Both pulse widths of a pulse signal, which is generated in relation to the rotation of the reel by the rotary pulse generator 1, and a reference pulse, which is formed according to the said pulse signal, are compared with each other in the comparator 4, and the fact that the number of rotations of the reel reaches a fixed value is detected to activate the alarm device at a fixed position of the tape. The output of the comparator 4 is connected to the output side of the delay circuit 3 through the feedback circuit 12, and is positively fed back to the input side of the comparator 4. The tape position is displayed in the display circuit 6 by turning on or off the output of the comparator 4 according to the pulse signal, no malfunction of the comparator 4 will take place even though a noise is produced in the comparator because the noise is absorbed by the capacitor C2 of the delay circuit 3.</p> |
