| 摘要 |
<p>PURPOSE: To automatically adjust tracking by making the width of two image heads provided in a rotating drum larger than the width of the video track of a tape, comparing the intensity of FM image signals reproduced and detecting an error voltage. CONSTITUTION: A first image head 2 and a second image head 3 are mutually installed at 180 deg. azimuth to a rotating head drum 1, the width D of heads 2 and 3 are made to be about 1.5 times larger than the width P of the video track. The second head 3 is positioned so that its lower end part conforms to the reference surface 4, and the first head 2 is positioned so that its upper end part is by the width P of the track higher than the reference surface 4. When the video track is correctly tracked, reproducing FM image signals of the same intensity are obtained in both heads 2 and 3. If the speed of the tape is fast, image signals of the head 2 become smaller than those of the head 3, while if the same is slow, image signals of the head 2 become larger. Therefore, if the speed of the tape is controlled so that image signals become same, tracking is correctly performed.</p> |
