CIRCUIT OPERATION

1-3) PB MODE

When playing the tape, the signal which is picked up from the tape is amplified 50 dB. Then luminance signal goes to pin 11 and color signal goes to pin 7 through AGC. Luminance signal of pin 11 is input to pin 39 of IC301 through PB EQ cir- cuit in order to match playback characteristic. Color signal which is output from pin 7 of IC401 is input to pin 15 of IC301. PB FM signal is demodulated by IC internal demodulator then it is input to pin 3 after MAIN DE-Emphasis process. If this output signal has burst, color component will be separated by X303. If it has burst, it is input to pin 4 of IC301 through Y- emphasis circuit. The signal which is input to pin 4 is output from pin 12 through 3.5M LPF, then it is input to pin 10 through 1H CCD. Color signal which is input to pin 15 passes ACC in order to stabilize level, then 3.58H components will be extracted by 3.58M BPF through Main Converter.

This 3.58M color signal is input to pin 25 of IC301 in order to eliminate crosstalk, then it will be mixed with luminance sig- nal after passing CNR circuit. Finally Y/C composite video signal is output from pin 34.

X302 IH DLY

V-OUT

V.IN

IC301

VIDEO IC

PB EQ

Y-EMPH

X303

Y/C

COMB

 

IC401

 

 

 

IC302

 

 

HEAD AMP

 

 

 

IH CCD

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

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Daewoo DV-K580NZ-T service manual X302 IH DLY