![background image](http://html.mh-extra.com/html/haier/htx21s31/htx21s31_service-manual_138159025.webp)
24
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 d. If alignment tool
f.
User Remote controller
g.
Service remote controller
h. Video signal generator i. Multi-system adjustment tool
j.
60MHz double trace oscillograph(2 units)
k
. White balance adjustment instrument
2). Signal, power supply connection:
a.C15V 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.
Adjustment
Summary of Contents for HTX21S31
Page 12: ...11 6 Net dimension Haier Net dimension ...
Page 19: ...18 11 Circuit Diagram Circuit Diagram ...
Page 22: ...21 PCB ...