| 摘要 |
<p>PURPOSE:To reduce time base fluctuation of a regenerated video signal caused by vibration on a tape, such as a VTR, etc., and to measure input time of a drum FG signal and a regenerated horizontal synchronizing signal by a simple constitution. CONSTITUTION:Gain changing means 23 and 24 are provided in a phase control system, and a gain of the phase control system at the time of controlling a speed of a drum motor with a speed error detected from the regenerated horizontal synchronizing signal is set smaller than that at the time of controlling a speed with a speed error detected from the drum FG signal by the gain changing mans. Then, changeover parts 29 and 30 for changing the drum FG signal and the regenerated horizontal synchronizing signal are provided, and its poststage is connected with a counter 14 for measuring input time. Input time of the two signals is measured with one counter by changing the two signals in each mode.</p> |
