| 摘要 |
<p>PURPOSE:To suppress the jitter of a reproducing image by amplifying and recording a color burst signal for a prescribed period, discriminating the position relation of the recording and a head, and controlling the tracking track of each head at the time of reproduction, in a 4-head type helical scan type device. CONSTITUTION:Four pieces of video heads R, L, R' and L' are placed at the interval of 90 deg., and a tape is wound to a rotary drum by 270 deg. or above. In this state, an AND gate to which a burst signal sampling pulse is applied is opened through a time width setting circuit to which an R head switching signal is supplied. Subsequently, an amplifier 6 is controlled, and at every two frames, a color burst signal is amplified and recorded by several H periods extending from the leading of a switching signal to a vertical blanking period. At the time of reproduction, this burst signal is detected, a switching circuit for a head output is controlled, each head executes tracking of the same track as the time of recording, and the jitter of a reproducing image based on an uneven rotation can be suppressed.</p> |
