Haier HTVF20R72, Service Manual

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VIF.SYS.SW (0:45.75M; 1:58.75M) OM8377
0-1 0
VIDEO.LEVEL Video Level (0~7)
0-7 7
FM.LEVEL FM Level (0~31)
0-31 16
POWER OPTION 0: 2 starts; 1: memory; 2 or 3: 1 start
0-3 0
SEARCH CHECK 0: w/out start auto search;
1: w/ start auto search
0-1
0
SEARCH SPEED 0: search slow; 1: search fast 0-1
1
AV OPTION 0: w/out AV; 1: 1-way AV input; 2: 2-way AV
input; 3: 3-way AV input
0-3 1
POSITION L/R 0: top left corner; 1: top right corner
0-1 1
BLACK BACK 0: No black back; 1: Black back
0-1 1
BLACK TRANS
0-1 1
V.MUTE P.OFF 0: video output not cut before POWER OFF;
1: video output cut before POWER OFF
0-1 0
CCD OPTION 0: CCD not used; 1: CCD used
0-1 1
V-CHIP OPTION 0: V-CHIP not used; 1: V-CHIP used
0-1 1
PASSWORD OPT. 0: V-CHIP not used; 1: V-CHIP used
0-1 1
TUNER OPTION 0:TDF-3M3 not used; 1: PHILIP UV1336B used
0-1 1
SCREEN OPTION 0:w/out curtain; 1: w/ at start; 2: w/ at close; 3:
w/ at start/close
0-3 0
SCREEN TIME
0-7 6
SCREEN HDC
0-63 0
BAND SELECT
0-1 0
3.Circuit signals processing
(1) MF amplifying circuit
Received by antanna and processed by the high frequency tuner, the television signals will be transmitted by the
tunner as 45.75MHZ signals to sound surface filter through C112 coupling after being amplified by V102, and then
the MF signals of trapped wave in sound carrier wave from sound surface filter F45U will be sent to pin 5 and 6 of
OM8377. The MF demodulation circuit of this TV set is completed through PLL carrier wave generator and outside
pressure control oscillator (T101) in OM8377. The MF frequency is adjusted by T101 adjustment, and output of
AFC is generated by a numerical control IF-PLL circuit, and read and sent to CPU by I
2
C bus for correction of MF
signals frequency deviation. The external capacitor of pin 3 decides the time constant of AGC
，
and high frequency
amplication AGC will be transmitted by I
2
C bus through pin 4 for control of high frequency tuner gain.
(2) Sound signals processing
Circuit Explanation