Haier TV-8888-03, Service Manual

Page: 26 / 30

26
Adjustment
IF alignment:
1). Test equipment:
a. 45.75MHz sweep generator
b. 15V/3A DC power supply (with short and over current proof)
c. Digital multi-meter
d. If alignment tool
e.
User Remote controller
f. Service remote controller
g. Video signal generator
h. Multi-system adjustment tool
i
. 60MHz double trace oscillograph (2 units)
j. White balance adjustment instrument
2). Signal, power supply connection:
Š
a. C15V DC power supply to the +15Vtesting top in the main PCB.
Š
b. Input sweep signal into IF testing top
Š
c. Connect multi-meter to PIF-TP testing top in PCB.
3). Alignment
a. Connect 45.75MHz sweep generator to IF test top in PCB
b. Adjust T101 and make digital multi-meter display 3.6V±0.05V.
(PIF-TP top can only connect to multi-meter).
Alignment and check :
a. Connect main PCB with alignment tool, input factory adjustment signal, and turn TV
on. Adjust screen control on FBT and make screen brightness relevant receive 525-
line monoscope, adjust focus control on FBT and make focus relevant.
b. Pre-adjust power voltage: adjust RP551 and make +B voltage be 136V±0.5V.
c. Check brightness, contrast, color, and sharpness: receive color bar signal and adjust
contrast, brightness, color, sharpness control, picture will change accordingly.
d. AV input check: press AV/TV button, screen will display AV mode or TV mode and
audio input signal can be observed; picture and sound must be normal.
Stereo adjustment :
Adjustment: Receive stereo signal (recommended audio: L 300Hz, R: 3KHz). Connect
two inputs of double trace oscillograph into XS601, XS602 (note: don’t make XS601,
XS602 outputs short.) Press FACTORY button on the service remote controller, enter
“ADJUST” service mode. Press “CH+” or “CH-” select “WIDEBAND” item and adjust low
frequency separation. (See figure 1) and make it Optimal (see figure)
Figure 1 Figure 2
Figure 3 Figure 4