| 摘要 |
<p>PURPOSE:To simplify the constitution and to perform excellent leading-in for VTR, by controlling the leading-in with the reference control pulse changed in the duty ratio depending on the program. CONSTITUTION:The variable delay one shot circuit 2 is triggered with the reference control pulse differentiated via the differentiating circuit 5, the circuit 2 produces the pulse different in duty ratio according to the program in synchronizing with the reference control pulse for the leading, and this is recorded ahead the program recording of the tape 6. When this recording is reproduced, the control amplifier 8 produces the pulse at the leading and trailing of the pulse different in duty ratio, the signal corresponding to the program is restored with the pulse corresponding to the trailing, and excellent leading-in with a simple constitution can be made without the use of the control track and being affected by the power supply variation due to duty ratio.</p> |
