Daewoo DV-K580DZ-T, Service Manual

Page: 16 / 59

15
CIRCUIT OPERATION
1-3) PB MODE
When playing the tape, the signal which is picked up from the tape is amplified 60 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 circuit 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 output to pin 3 after MAIN DE-Emphasis process. If this output signal has burst,
color component will be separated by 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 2H CCD. Color signal which is input to pin 15
passes ACC in order to stabilize level, then 4.43M components will be extracted by 4.43M BPF through
Main Converter.
This 4.4Mhz color signal removes crosstalk component through X302 and is input to pin 29 of IC301
then it will be mixed with luminance signal after passing CNR circuit. Finally Y/C composite video signal
is output from pin 34.
V-OUT
V.IN
IC401
HEAD AMP
X302 2H DLY
Y-EMPH
IC302
2H CCD
IC301
VIDEO IC
PB EQ