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Title:
AUTOMATIC FREQUENCY CONTROL CIRCUIT
Document Type and Number:
Japanese Patent JPH0294927
Kind Code:
A
Abstract:

PURPOSE: To improve picture distortion occurring when a VTR is reproduced in a special manner by supplying AFC(automatic frequency control) error voltage to the AFC circuit of a horizontal deflection circuit using another AFC circuit to be used when a flicker reduction circuit is composed.

CONSTITUTION: The control circuit is equipped with a phase detecting means 3 to compare the phase of a horizontal synchronizing signal with the phase of a horizontal reference signal and a filter means 4 to smooth the output voltage of the phase detecting means 3 and generate the AFC error voltage. Further, the AFC error voltage from the filter means 4 is superimposed on a voltage controlled oscillator 12 of an automatic frequency control circuit 30 of the horizontal deflection circuit. Consequently, this AFC circuit 10 superimposes the error voltage from the AFC circuit for generating a clock signal on the error voltage of the AFC circuit for deflecting voltage, and a skew which cannot be followed up by the AFC circuit to generate a clock can be corrected by the deflection circuit AFC circuit 10. Thus, the picture distortion to occur in a part having no noise bar when a video tape recorder is reproduced in the special manner can be improved.


Inventors:
TSUNETOMI YOSHINOBU
KAWABUCHI SEIJI
SARUGAKU TOSHIO
NAITO HIDEFUMI
Application Number:
JP24649188A
Publication Date:
April 05, 1990
Filing Date:
September 30, 1988
Export Citation:
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Assignee:
SONY CORP
International Classes:
H04N5/50; H04B1/16; H04N5/12; (IPC1-7): H04B1/16; H04N5/50
Domestic Patent References:
JPS6287391U1987-06-04
JPS62159980A1987-07-15
JPS6223284A1987-01-31
JPS5271922A1977-06-15
JPS63185171A1988-07-30
Attorney, Agent or Firm:
Sada Ito (1 person outside)



 
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