| 摘要 |
PURPOSE:To attain skew correction almost not causing phase discontinuity of chrominance signal subcarrier with simple constitution by using a crystal oscillator so as to oscillate a frequency signal being 4 times the chrominance signal subcarrier frequency so as to use it as a clock of a CCD delay line, applying 1/4 frequency division to the signal so as to use it as a reference signal of an APC circuit of the reproduced color signal processing. CONSTITUTION:The crystal oscillator 18 is oscillated at a frequency being 4 times the chrominance signal subcarrier frequency. Then the output signal is inputted to a CCD delay line 19 giving a delay of 0.5H as a clock. Simultaneously, the output signal of the crystal oscillator 18 is subjected to 1/4 frequency division by a 1/4 frequency divider 20 and outputted as a signal of the chrominance signal subcarrier frequency. Moreover, the signal of the chrominance signal subcarrier frequency outputted form the 1/4 frequency divider 20 is inputted to a reproduced color signal processing circuit 7 and become a reference signal of a reproduced APC circuit. Thus, the phase of the subcarrier of the recovered chominance signal outputted from the recovered chrominance signal processing circuit is locked completely to the phase of the signal of the chrominance signal subcarrier frequency outputted from the 1/4 frequency divider 20. Moreover, the phase of the subcarrier wave of the reproduced color signal is locked to the phase of the clock signal inputted to the CCD delay line 19.
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