| 摘要 |
<p>PURPOSE:To prevent unnecessary recording/reproduction by detecting a tape recording signal or presence of a reproducing signal and starting a timer with a signal absence detecting signal so as to switch the mode of a mechanism from the recording to stop, from reproduction to stop or reversible reproduction after a prescribed period. CONSTITUTION:An AD converter 13 detects the presence of a tape recording signal or a reproducing signal, applies the signal to an FF14 and the FF14 is reset by power application and mode switching of the mechanism. An AND gate 17 outputs a timer start signal during the input of non-detection signal while the FF14 is set and outputs a timer reset signal at the input of presence detecting signal while the FF14 is reset or set. A timer 29 outputs a period end signal from the start of input of the timer start signal after a prescribed period. A plunger 4 uses the period end signal so as to switch the mode of mechanism from the recording to stop, from reproduction to stop, or tape ejection or reverse reproduction through fast feeding. Thus, unnecessary recording/reproduction is prevented.</p> |
