| 摘要 |
PURPOSE:To eliminate a deficiency of a vertical synchronizing signal even at a special reproducing mode in terms of tape speed and to prevent a switching point from fluctuation by detecting a equivalent pulse of a reproduced image signal of an amplifier circuit and a decoding circuit provided on plural rotational magnetic heads so as to switch a head output. CONSTITUTION:Signals reproduced by the 1st and 2nd rotational magnetic heads 8 and 9 from an image track recorded on a magnetic tape 1 are amplified by the 1st and 2nd amplifier circuits 10 and 11. Demodulating circuits 12 and 13 decode reproduced signals A and B to image signals, and reproduced image signals can be obtained. Equivalent pulse detection circuit 14 and 15 are set so that they can output equivalent pulse detection signals at a position of 1.25H from a start of an equivalent pulse; therefore vertical synchronizing signals will not be lacking at a two-fold speed mode, and moreover image signals recorded on the magnetic tape 1 can be reproduced without fluctuation of a switching point 7. |
