| 摘要 |
PURPOSE:To obtain a video signal having no missing part at the special reprodution mode by means of the automatic scanning tracking (AST) by providing a gate circuit detecting a reproducing signal period of two rotary magnetic heads respectively so as to obtain a head output switching signal by the gate circuit. CONSTITUTION:The signal reproduced from the video track recorded on a magnetic tape 1 by the 1st rotary magnetic head 8 and the 2nd rotary magnetic head 9 is amplified by the 1st and 2nd amplifier circuits 10, 11 and reproducing signals A, B are fed to a changeover switch 15. Gate circuits 12, 13 output gate signals C, D for a period when the reproducing signals A and B are a prescribed level or over so as to detect the presence or absence of the reproducing signal. The gate signals C, D are fed to a head output changeover signal circuit 14 so as to form a head output switching signal E rising at a position delayed by a prescribed time from the leading of the gate signal C and descending at a position delayed by prescribed time from the leading of the gate signal D. The switch 15 is changed over by the head output switching signal E. |
