| 摘要 |
<p>A video recorder with automatic still picture positioning senses during moving picture mode the levels of the waveform of the FM signal for successive fields and calculates a ratio from these levels. In still picture mode, the waveform levels are measured at respectively corresponding angular positions with respect to head switching pulses, and level ratios are likewise calculated. These actual level ratios are compared with set level ratios, as have been obtained from the moving picture level ratios in consideration of geometrical characteristics of the playback arrangement. From the deviations between level set values and level actual values, a respective tape position correction value is obtained. By constantly matching the level set values to the current ratios, it is ensured that the tape position correction values are appropriate for the current ratios. <IMAGE></p> |
