| 摘要 |
PURPOSE:To prevent frequency characteristics, linearity, etc., from deteriorating and to eliminate beat interference and an inversion phenomenon with regard to a dubbing system for color video signals, by mixing a low-frequency converted chrominance signal and luminance signal to be frequency-modulated and by recording the mixture direct on a recording medium. CONSTITUTION:A color video signal from input terminal 1 is processed in the normal method to obtain a frequency-division multiplex signal, which is recorded on recording medium A. From this recording medium A (A'), the above-mentioned frequency-division multiplex signal is reproduced by reproducing head 12 and passed through low-pass filter 23 to obtain a low-frequency converted chrominance signal, which is level-adjusted and then applied to one input terminal of mixer 25. Further, a luminance signal to be frequency-modulated is obtained from the above- mentioned reproduced signal and the compensation of frequency deterioration, averaging of upper and lower side-band waves, compensation of the frequency decreased of a carrier component, and removal of fluctuations of amplitude are carried out to record on recording medium B the output of mixer 25 applied to the other three inputs mixer 25. By such a dubbing system, the occurrence of an inversion phenomenon can be prevented, frequency characteristics, pulse characteristics and linearity is improved and beat interference is also reduced. |
