| 摘要 |
PURPOSE:To improve the preciseness of index signals by removing a phase error in the index signal detected by a false sigal generated so as to include the phase error due to chromatic scanning, color and luminance signals. CONSTITUTION:A chromatic scanning signal generator 12 produces a chromatic scanning signal from a color signal from a terminal 15, a subcarrier from a terminal 7 and an output from a frequency converter 5 and the chromatic scanning signal is inputted to an adder 13 to generate a false signal composed of a luminance signal and a color sinal. The false signal is inputted to the frequency converter 5 through a multiplier 7 and a band pass amplifier 8 and the phase error is made to ''0'' by obtaining the frequency of the difference between the frequency of the false signal and that of an index signal from a filter 4. The sum of the frequency of the false signal and that of the color signal is found by a sum frequency converter 9 and composed with the luminance signal by the adder 10 to obtain a writing signal. Thus, preciseness of index signals can be improved. |
