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Monos pattern
10-step gray scale
10-step gray scale
3-5. VCOM-DC Adjustment
1. Preparation
• AC adaptor or voltage regulator
• Photo sensor / photo sensor amplifier (C2719)/Low-Pass filter)
• Digital oscilloscope
2. Adjustment procedure
(1) Turn POWER on while pressing DISP key and MENU button simultaneously
(2) Quickly press keys in the order of FLASH key, FLASH key and MENU key.
(3) Select / Execute 50PERCENT GRAY.
(4) Monitor the photo sensor amplifier output via a low-pass filter of cutoff frequency 60Hz.
Monitoring the oscilloscope screen, adjust VR321 to minimize 60Hz ripple waveform.
3. Notes
Perform the adjustment after you replaced the LCD display module or L-PCB Assy.
4. Connection diagram / block diagram
Photo diode
S1153
L.P.F
Photo sensor amp.
C2719
Minimize the
ripple components
Oscilloscope
LCD
QV-8000SX
(Reference) Simplified adjustment method
Take an image of the monoscope pattern using the camera, and adjust VR321so that the 10-
step gray scale will be in its best condition.
Summary of Contents for QV-8000SX
Page 1: ...R QV 8000SX OCT 1999 without price KX 714 Ver 2 Dec 1999 ...
Page 38: ... 36 63 All parts separated 62 Remove DP panel 61 Unhook DP panel from behind and push it out ...
Page 45: ... 43 C PCB PCB K714D C PRINTED CIRCUIT BOARDS ...
Page 46: ... 44 D PCB PCB K714D D ...
Page 47: ... 45 L PCB PCB K714D L ...
Page 48: ... 46 MD PCB PCB K714D MD ST PCB PCB K714D ST ...
Page 49: ... 47 SCHEMATIC DIAGRAMS C PCB PCB K714D C CIRCUIT ...
Page 50: ... 48 D PCB PCB K714D C CIRCUIT ...
Page 51: ... 49 L PCB PCB K714D C CIRCUIT ...
Page 52: ... 50 MD PCB PCB K714D C CIRCUIT ...
Page 53: ... 51 ST PCB PCB K714D C CIRCUIT ...
