Patent ID: 6753924
Filing Date: 2004-06-22
Classification: H04N

Abstract:
An oscillation signal processing apparatus for oscillating a subcarrier to demodulate a color difference signal from a carrier chrominance signal, comprising:PLL oscillation unit that performs predetermined oscillation synchronized with a color burst signal by a predetermined PLL and outputting an oscillation output as the subcarrier; external output unit that outputs the oscillation output from said PLL oscillation unit as a reference signal for an external tuner; and PLL oscillation control unit that controls said PLL oscillation unit to stop a phase comparison operation upon start of tuning operation by said external tuner, so as to stabilize the reference signal from said external output unit; wherein said PLL oscillation unit has a burst amplification circuit which performs predetermined amplification so as to reduce amplitude variation of the color burst signal before the phase comparison operation, and wherein said PLL oscillation control unit has a switch to reduce a gain of the burst amplification circuit to a minimum.