Adjustment - Casio CTK-591 Service Manual

DISPLAY PCB
1) Items to be adjusted:
Item
Vop voltage setting
2) Adjustment and Test Point Locations
VD5
30 pin
33 pin
VLCD
3) Equipment connection/Procedure
Input Input
Connection Point
Eye
34.9°
LCD

ADJUSTMENT

Voltmeter
(TOP VIEW)
Vop voltage setting
Set
Output
VLCD
VD5
Input Output
Adjust
Signal Connection
VR1 Voltmeter
Watching the LCD at a 34.9° angle to the horizontal, adjust Vop
voltage so that unenergized segments are seen dimly.
— 5 —
Measuring Instrument
Voltmeter
Output
Point
VLCD- Adjust for 4.2 ~ 4.3 V reading
VD5 on voltmeter under the tem-
perature 20 ~ 25 °C.
Make fine adjustment accord-
ing to the next instruction.
Adjust for