| 摘要 |
PURPOSE:To prevent a pattern of a receiver from becoming a black/white picture and to reduce the disturbance such as cross color and cross luminance by modulating a color difference signal with a chrominance subcarrier whose phase is inverted at least at each frame. CONSTITUTION:The frame frequency of a 1st television signal (MUSE signal) is not converted but the field frequency is left. An output of a voltage controlled crystal oscillator 35 oscillating a 4 multiple color subcarrier frequency is frequency-divided by a frequency divider 32, outputs of frequency divider 32, 31 are compared by a phase comparator 33 and a phase error component is eliminated at an LPF 34 and the resulting signal is fed to a control terminal. Thus, the oscillating frequency of the voltage controlled crystal oscillator 35 is phase-locked to a clock of High Vision signal system. |
