| 摘要 |
PURPOSE:To commonly use a preamplifier for each system, by selecting the speed ratio of each system so as to equalize the frequencies at the white peak approximately, in dubbing a video signal of television systems. CONSTITUTION:A discrimination circuit 40 is connected to a synchronizing separation circuit 18 for the switching of speed ratios N1 and N2, and a reference signal generator 27, speed error detection circuits 26 and 35 are controlled with this discrimination signal, the discrimination signal is picked up at a terminal 11e and the frequency dividing ratio of the reference signal generator 27 is switched. Further, the speed of the circuits 26 and 35 is switched with the discrimination signal and the revolving speed of a capstan motor 31 and a drum motor 39 is switched to N1 or N2 times the normal speed. |
