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5. Adjusting Procedure
5-1 Adjustment conditions and precautions
1.
Approximately 30 minutes should be allowed for warm up before proceeding.
2. Adjustments should be undertaken only on those necessary elements since most of them have been carefully preset
at the factory.
5-2 Main adjustments
NO.
FUNCTION LOCATION
DESIGNATION
1.
14V ADJ
PCB - MAIN
VR903
2.
B + ADJ
PCB - MAIN
VR902
3.
SCREEN ADJ
FLY BACK TRANS
T402 SCREEN VR
4.
FOCUS ADJ
FLY BACK TRANS
T402
FOCUS
VR1&VR2
5.
ABL ADJ
PCB - MAIN
AB in factory OSD
6.
FUNCTION ADJ -MENU
PCB - MAIN
(SW101)
-UP
▲
PCB - MAIN
(SW102)
-DOWN
▼
PCB - MAIN
(SW103)
-SELECT
PCB - MAIN
(SW104)
5-3 Adjustment method
1. 14V, B + & HV voltage adjustment:
A. Chroma-2000 Signal generator or PC equivalent set mode 1, VGA 640
X
480 pattern 1.0.
B. Connect a DC Volt meter between TP901 and ground, then adjust VR903to be 14VDC.
C. Connect a DC Volt meter between TP902 and ground, then adjust VR902 to be 65.5 VDC.
2. Factory preset Timings Adjustment:
A. Press
Key to show OSD window press Up or Down Key to switch the functional controls.
B. Press the Up Key to select the "ZOOM" function, then press the MENU Key. While do not release the MENU Key
until the OSD window changed to the Factory preset window.
C. The Factory preset window contains the following functional controls. Select one of the control. Then press the
Up/Down Key to adjust its value for the optimum picture.
ViewSonic Corporation
Confidential - Do Not Copy
G90fB-4
13
Содержание G90fB-4
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Страница 53: ...11 PCB Layout Diagrams 11 1 Main PCB Layout ViewSonic Corporation Confidential Do Not Copy G90fB 4 50...
Страница 54: ...11 2 CRPC Board Layout ViewSonic Corporation Confidential Do Not Copy G90fB 4 51...