Adjustment - Haier HTX21S31 Service Manual

13. 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
f. User Remote controller
h. Video signal generator
j. 60MHz double trace oscillograph(2 units)
k. White balance adjustment instrument
2). Signal, power supply connection:
a.Connect +15V DC power supply to the +15V testing top in the main PCB.
b.Input sweep signal into IF testing top
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 109V±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.
S
optimal.
d. If alignment tool
g. Service remote controller
i. Multi-system adjustment tool
24
Adjustment