| 摘要 |
PURPOSE:To check a servo system without including a video signal system by making in possible to select optionally phase control of a capstan motor including a video signal processing system and that independent of the video signal processing system. CONSTITUTION:When the state of a switching circuit 11 is so set by a switching control signal (b) that a phase control signal (c) from a phase control circuit 8 is supplied to an adding circuit 12, a pilot signal reproduced by a rotary head 6 is used to perform phase control of a capstan motor 1, and tracking control of the rotary head is performed with a high precision. In case of check of the servo system is an assembling process or a repair work of a VTR, the switching circuit 11 is so switched that a phase control signal (d) from a phase control circuit 10 is supplied to the adding circuit 12, and thereby, the servo system is constituted into a closed loop without passing a video signal reproducing circuit 7. |
