| 摘要 |
PURPOSE:To facilitate considerably a tape travelling control operation when the VTR parts are assembled by performing the tracking control based on the information only on some sections of a video track. CONSTITUTION:A pulse of width T1 is produced from a pulse generating circuit 32 with a delay of time Td compared with a head switching pulse. The output of a voltage comparator 21 is sampled by the pulse T1. This sampled output is held for the period of are field to eliminate the complicated tape driving control. In other words, the error information obtained from a video track is used as a tracking detecting signal after sampling it at a fixed position and for a fixed time width. Furthermore, the tracking detection output corresponding to the track linearity is extracted by shifting the sampling point to facilitate the easy checking of the linearity of a track pattern. |
