| 摘要 |
<p>PURPOSE:To prevent malfunction when erasing a tape, by making always to be in normal state automatically by means of a logical circuit when taking out a cassette. CONSTITUTION:If a changeover switch 3a of an LL changeover switching circuit 3 is closed, the output of the circuit 3 becomes level H to set an FF8, whose output Q becomes level H. Therefore, the second track of a tape becomes to be sound recording authorized state through an OR circuit 9, and the first track becomes to be sound recording prohibit state through an NOR circuit 10. The output of a normal changover switching circuit 4 becomes level H, if a changeover switch 4a of the switching circuit 4 is closed, to reset the FF8 through an OR circuit 11, and its output becomes level L. Thus, both of the first and the second tracks are given sound recording authorized state, if the miss erasing preventive tip of a cassette is not broken. If the cassette taking-out operation is performed, the output of an eject detection circuit 5 becomes level H and is supplied to the circuit 11, and the following operation is the same as when the switch 4a is closed.</p> |
