![background image](http://html1.mh-extra.com/html/viewsonic/a90f-1/a90f-1_service-manual_1020116023.webp)
c). Brightness at center, contrast at maximum.
d). Adjust R827 for the voltage to 82V of D816 .
7-2 High voltage
a). Apply Chroma 2225 signals with 31.47kHz / 60Hz (640 x 480) Mode and full white pattern to the
monitor.
b). Connect AC input and power on the monitor.
c) ..Brightness at center, contrast at maximum.
d) .Adjust R176 for Normal high voltage = 25.9 kV
7-3 Full brightness setting (Timing Mode 13)
a) .Apply Chroma 2225 signals with full white pattern to the monitor.
b). Connect AC input and power on the monitor.
c). Brightness at center, contrast at maximum.
d). Adjust preset Horizontal and vertical size.
e). Set R, G, B bias and Gain (follow color temp. adjustment procedure)
f). Adjust R167 to get 29+/-1FL
7-4 OSD Adjustment (See the table below), (Enter Factory preset OSD Menu)
Turn on the monitor by pressing power switch and OSD on/off key at the same time, release power
switch and continue to press enter key, then release the enter key after display appears.
ViewSonic Corporation
20
Confidential – Do Not Copy
A
9
0f+-1
Summary of Contents for A90f+ 1
Page 57: ...12 PCB Layout ViewSonic Corporation 54 Confidential Do Not Copy A90f 1...
Page 58: ...VIDEO PWB 0414 ViewSonic Corporation 55 Confidential Do Not Copy A90f 1...
Page 59: ...KEY CONTROL PWB 0488 ViewSonic Corporation 56 Confidential Do Not Copy A90f 1...
Page 60: ...MAIN BOARD 13 Schematic Diagrams ViewSonic Corporation 57 Confidential Do Not Copy A90f 1...
Page 61: ...VIDEO ViewSonic Corporation 58 Confidential Do Not Copy A90f 1...
Page 62: ...KEY CORTROL ViewSonic Corporation 59 Confidential Do Not Copy A90f 1...
Page 63: ...POWER SUPPLY CKT ViewSonic Corporation 60 Confidential Do Not Copy A90f 1...
Page 64: ...MCU CONTROL CKT ViewSonic Corporation 61 Confidential Do Not Copy A90f 1...
Page 65: ...Time Base DeflectionCKT ViewSonic Corporation 62 Confidential Do Not Copy A90f 1...
Page 66: ...H V DYNAMIC FOCUS CKT ViewSonic Corporation 63 Confidential Do Not Copy A90f 1...
Page 67: ...14 Exploded Diagram ViewSonic Corporation 64 Confidential Do Not Copy A90f 1...