XOCECO LC17H3S, Руководство по обслуживанию

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2.Adjustment and calibration deacription
2.1 Method to enter factory menu
Push MUTE-MENU-OK-SLEEP key in turn at the interval of 1 second
2.2 Adjustment and calibration equipment
Digital multi-meter, signal generator (with SCART/RGB signal output), oscillograph,
PC set ( preset the program of flash written), K7253(VGA signal generator), CA210
(LCD white balancer) DVD displayer, TV with SCART connector 1 set, IF signal
generator
2.3 Written program
Writing the memory unit N4, N20, N303, N302
2.4 Main board adjustment and calibration
a) Main board X501 Connect infra-red receiving board (as per connect diagram),
insert the output plug of power supply adapter(FSP048-1AD101C for 15,
FSP060-1AD103 for 17,20’) into X1, when the indication lamp of infra-red receiving
board should be in red
b) Connect PC set. Run FLASH N20 upgrade program, push POWER key on the
remote control set, when the indication lamp of infra-red receiving board should be in
red
c) About 4 minutes later, indication lamp of infra-red receiving board turns to
yellow/blue (LC-15H4 S/17H4 S/20H4 S), measure L102 PIN2 5.0 V,L107 PIN2 3.3
V, N10 PIN2 1.8 V, and N12 PIN2 1.8 V.
d) Write DDC program
2.4 TV board adjustment
2.5.1 IF adjustment
a) Input DV 5V into TP2, input 12V to TP6, Input 5V to TP4 and input 0V to TP5,
monitor voltage of TP3, input 38.9 MHz signal to TP1, and use a non-inductance screw
driver to adjust IFT L207 so that TP3 voltage is 1.65V
b) Input DC 5V into TP2, input 12V to TP6, Input 0V to TP4 and input 5V to TP5,
monitor voltage of TP3, input 33.9 MHz signal to TP1, adjust
potential meter RP202 to
set TP3 voltage to 1.65V.
c) Connect IF line of tuner, control line L and L’: three disconnected points in total.
2.5.2 Connection of the complete set
Connect main board, TV board, infra-red receiving board (as per connect diagram),
push POWER key on the remoter control set, when the indication lamp of infra-red
receiving board is in yellow/blue (LC-15H4 S/17H4 S/20H4 S),measure PIN2 of
N301to be 3.3 V on TV board, one end of SMT conductance L632 to be 5V, another
end of SMT conductance L632 to be 12V.
2.5.3 AGC Adjustment
Receive D-8 signal of 60 db, measure the voltage of positive pole of D201 with DC
potential meter.
Adjust potential meter RP201 to make reading of potential meter just decrease below
4.0V.Input 100db from antenna, the picture should not appear non-synchronized and
distorted, input weak signal of 35 dB--40 dB, color should not disappear, picture
synchronizes, normal sound.
2.6 Wht balance adjustment ( Use LCD special white balancer CA210,K7253 signal