| 摘要 |
<p>PURPOSE:To avoid the signal detection level and the time setting of non-signal state from being fluctuated due to power supply voltage, by detecting the non-signal state of the signal source through the use of the delay circuit. CONSTITUTION:The circuit detects the non-signal state at the tape reproducing unit, and the signal from the signal source 1 such as magnetic tape is fed to the rectifying circuit 3 via the coupling capacitors 11, 12 and amplifier 2. The switch circuit 6 turns on and off depending on the level of this rectified voltage. Further, when the switch circuit 6 is OFF with non-signal state, the delay circuit 7 is operated to output the output from the terminal 5.</p> |
