Acer AC701 User manual

1
1. DISPLAY ALIGNMENT..............................................................................2
A. TIMING & DISPLAY SIZE..........................................................................................................................2
B. PICTURE POSITION.................................................................................................................................2
C. LINEARITY ................................................................................................................................................2
D. ALIGNMENT PROCEDURE......................................................................................................................2
E. GEOMETRIC DISTORTION......................................................................................................................3
F. WHITE BALANCE ALIGNMENT ................................................................................................................4
2. CONTROL AND CONNECT LAYOUT.......................................................6
A. MAIN PCB..................................................................................................................................................6
C. PIN ASSIGNMENT....................................................................................................................................8
3. INTRODUCTION: ...................................................................................... 9
A. POWER SUPPLY.......................................................................................................................................9
B. DEFLECTION: ...........................................................................................................................................9
C. VIDEO:.......................................................................................................................................................9
D. DIGITAL CONTROLLOR:..........................................................................................................................9
4. POWER SUPPLY .................................................................................... 12
A. RECTIFIER AND FILTER CKT: ...............................................................................................................12
B. FLYBACK AND PWM CKT :....................................................................................................................12
C. SNUBBER CKT:.......................................................................................................................................12
D. SYNCHRONIZED CKT: ...........................................................................................................................12
E. POWER SAVING CKT: ............................................................................................................................12
F. DEGAUSS CKT: .......................................................................................................................................13
G. OVERLOAD PROTECTION CKT:...........................................................................................................13
5. DEFLECTION..........................................................................................14
A. SYNC RPOCESSOR:..............................................................................................................................14
B. HORIZONTAL PROCESSOR..................................................................................................................14
C. VERTICAL OUTPUT................................................................................................................................14
D. HORIZONTAL OUTPUT STAGE.............................................................................................................14
E. FLYBLACK TRANSFORMER..................................................................................................................14
6. VIDEO AMP. CIRCUIT............................................................................. 17
A. VIDEO PRE. AMP....................................................................................................................................17
B. VIDEO AMPLIFIER..................................................................................................................................17
7. TROUBLESHOOTING.............................................................................19
A. POWER SUPPLY CHECK.......................................................................................................................19
B. MONITOR CHECK FLOW CHART..........................................................................................................20
APPENDIX A: PARTS LISTS......................................................................23
APPENDIX B: P. C. B. ASSEMBLY ...........................................................36
APPENDIX C: DISPLAY UNIT ASSEMBLY ..............................................54
APPENDIX D: CRT & YOKE ASSEMBLY .................................................58

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1. DISPLAY ALIGNMENT
A. TIMING & DISPLAY SIZE
For all presetting mode shall be within the limitation:
H. WIDTH 310 ± 5mm
V. HEIGHT 232 ± 3 mm
The external control range of the data area, shall be as follows;
Max. horizontal size : full the screen
Max. vertical size : full the screen
B. PICTURE POSITION
For all presetting mode shall be within the limitation:
H.PHASE SCREEN CENTER ± 4 mm
V.CENTER SCREEN CENTER ± 3 mm
C. LINEARITY
The linearity of an image displayed on the CRT must meet the following requirements, with reference to figure
4.05 for both X and Y and axis.
The measured value of linearity shall be less than 6%(p) or 8%(s) when calculated using all lattices and shall be
less than 5%(p) or 6%(s) when calculated using adjcent lattices.
Xmax-Xmin OR Ymax-Ymin
Xmax+Xmin Ymax+Ymin
Where: Xmax,Xmin,be Calculated Same Line
Ymax,Ymin,be Calculated Same Row
D. ALIGNMENT PROCEDURE
• Warm up the monitor for at least 30 minutes before adjustment.
• Set the front of CRT to the east.
• Turn all VR set to center position.
D-1. H.V
1. Use front control key adjust the display size about 300mm, adjust VR801 Let the Plus of C824 is
28.14V in Timing 68kmode FULL WHITE PATTERN, it can be got a stable H.V.

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E. GEOMETRIC DISTORTION
E-1 Raster Rotation
SignalNo.1to6
|a - b |≤2.0 mm a
b
Bezel
E-2 Pincushion
SignalNo.1to6
Top :d1≤2.0 mm
Bottom :b1≤2.0 mm
Leftside :a1≤1.5 mm
Rightside :c1≤1.5 mm
a1
b1
c1
d1
E-3 Barrel
SignalNo.1to6
Top :d2≤2.0 mm
Bottom :b2≤2.0 mm
Leftside :a2≤1.0 mm
Rightside :c2≤1.0 mm
a2
b2
c2
d2
E-4 Trapezoid
Signal No.1 to 6
Top :d≤2.5 mm
Bottom :b≤2.5 mm
Leftside :a≤2.5 mm
Rightside :c≤2.5 mm
c
b
a
d
E-5 . Parallelogram
Signal No.1 to 6
a≤0.5 degree a
E-6 Overall Distortion
SignalNo.6only
Top :d≤2.5 mm
Bottom :b≤2.5 mm
Leftside :a≤2.5 mm
Rightside :c≤2.5 mm
c
b
a
d

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F. WHITE BALANCE ALIGNMENT
F.1.1 Select timing #6 (VESA 68K 1024X768) with crosshatch pattern, adjust both horizontal and vertical
OSD’s size control to get display size within 310x232p±2mm.
F.1.2 Disconnect R.G.B. signal inputs, adjust OSD’s brightness and G1 control to it’s maximum position.
F.1.3 Auto alignment(P103 must be short)
Use automatic alignment equipment and program to get color temperature within specified
coordinates.
F.1.4 Manual alignment
P103 must be short in order to into factory mode. Select OSD function to color temperature
adjustment.
F.1.5 For 9300( 7500 ; 6500 ) color coordinate ( notes: set the minimum value of R.G.B. bias is 0,
set the value of sub-contrast “SC” is 0 ).
F.1.6 Disable the video pattern( for a raster pattern ), set the maximum value of contrast and
brightness is 255, adjust G1 to Y=0.01 cd/mm
F.1.7 Adjust bias G to get Y=1.8
±
0.06 cd/mm
Adjust bias B to get y=297 ( y=315 for 7500 ; y=329 for 6500 )
±
5
Adjust bias R to get x=283 ( x=295 for 7500 ; x=313 for 6500 )
±
3
F.1.8 Fine tune the bias G and R for x=283 , y=297 ( x=299, y=315 for 7500; x=313, y=329 for
6500 )
±
3.
F.1.9 Select 7500 and 6500 color coordinate separately. Repeat item 2.5.5 ~ 2.5.8 to
meetspecificity.
F.1.10 Adjust brightness control to get raster is <= 0.25cd/mm, change pattern to 2 inch square.
F.1.11 Enable G signal output of pattern generator, adjust gain G to get Y=98
±
1 cd/mm
F.1.12 Enable B signal output, adjust gain B to get y=297 ( y=315 for 7500 ; y=329 for 6500 )
±
2
Enable B signal output, adjust gain R to get x=283 ( x=299 for 7500 ; x=313 for 6500 )
±
1
F.1.13 Fine tune the gain G and R for x=283 , y=297
( x=299, y=315 for 7500; x=313, y=329, for 6500 )
±
2
F.1.14 Check 150 >Y> 130 cd/mm, if not , adjust G to get Y>130 cd/mm, then repeat item 2.5.12
F.1.15 Change pattern to fall white, adjust SB to get 92< Y <113 cd/mm .
F.1.16 Select 7500 and 6500 color coordinate separately. Repeat item 2.5.11 ~ 2.5.15 to meet
specificity.
7500 X=300 Y=315
6500 X=313 Y=329

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G. PRESET TIMING
Preset Timing Chart
No
Signal Name Clock
(MHz)
Fh
(kHz)
Fv
(Hz)
Th
(uSec)
(dot)
Tsh
(uSec)
(dot)
Tfh
(uSec)
(dot)
Tbh
(uSec)
(dot)
Tdh
(uSec)
(dot)
Tv
(mSec)
(line)
Tsv
(mSec)
(line)
Tfv
(mSec)
(line)
Tbv
(mSec)
(line)
Tdv
(mSec)
(line)
Hs Vs
1 VGA
640*480(60) 25.175 31.469 59.940 31.778 (800) 3.813 (96) 0.636 (16) 1.907 (48) 25.422 (640) 16.683 (525) 0.064 (2) 0.318 (10) 1.049 (33) 15.253 (480) - -
2 VESA
800*600(85) 56.250 53.674 85.061 18.631 (1048) 1.138 (64) 1.138 (64) 2.702 (152) 14.222 (800) 11.756 (631) 0.056 (3) 0.019 (1) 0.503 (27) 11.179 (600) + +
3 VESA
1024*768(85) 94.500 68.677 84.997 14.561 (1376) 1.016 (96) 0.508 (48) 2.201 (208) 10.836 (1024) 11.765 (808) 0.044 (3) 0.015 (1) 0.524 (36) 11.183 (768) + +
4 VESA
800*600(75) 49.500 46.875 75.000 21.333 (1056) 1.616 (80) 0.323 (16) 3.232 (160) 16.162 (800) 13.333 (625) 0.064 (3) 0.021 (1) 0.448 (21) 12.800 (600) + +
5 VESA
1024*768(75) 78.750 60.023 75.029 16.66 (1312) 1.219 (96) 0.203 (16) 2.235 (176) 13.003 (1024) 13.328 (800) 0.050 (3) 0.017 (1) 0.466 (28) 12.795 (768) + +
6 VESA
1280*1024(60) 108.00 63.981 60.020 15.630 (1688) 1.037 (112) 0.444 (48) 2.296 (248) 11.852 (1280) 16.661 (1066) 0.047 (3) 0.016 (1) 0.594 (38) 16.005 (1024) + +
Tbh
Tbv
Th
Tdh
Tfh
Tsh
Tsv
Tv
Tdv
Tfv
[ H-SYNC ]
[ V-SYNC ]
[ VIDEO ]
[ VIDEO ]

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2. CONTROL AND CONNECT LAYOUT
A. Main PCB

7
B. VIDEO PCB

8
C. PIN ASSIGNMENT
C-1. Connect Table
P102 P105-P202 P104-P203
1 DETECT V-OUT AFC
2 DDC-SCL OSD-SDA GHD
3 DDC-SDA OSD-SCL G1
4 GND H-out HEATER
5 V-sync GND 5V
6 H-sync 80V
7 5V from PC 12V
8 ABL
9
10
C-2. Connect Function
P803 : H-CENTER CONN
P501 : TILT CONN
P103: PRESET CONN
P902 : DEGAUSSING COIL CONN
P804 : X-RAY TEST PAD

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3. INTRODUCTION:
C708 is a 17” multisync color monitor. The horizontal frequency range is from 30khz to
70khz, and the refresh rate is from 50hz to 160hz. The circuit includes four major parts, the
power supply circuit, the deflection circuit, the video circuit and the digital control circuit. is
the function block diagram.
A. POWER SUPPLY
Transfer AC source to DC source that supply all the circuit power. It includes:
(1) +13.5V: For horizontal and vertical deflection circuit.
(2) –11.5V: For vertical deflection circuit.
(3) +7.2V: For CRT heater, parts of video pre-amp circuit.
(4) +53V: For B+Boost circuit.
(5) +80V: For video circuit
(6) 9.2V: for MIRCO- P
Fig 2 is the function block diagram of power CKT.
B. DEFLECTION:
Produce YOKE deflection current of horizontal and vertical, CRT H.V and bias that makes
screen raster.
C. VIDEO:
amplify the video signal and add the signal to the cathode of CRT to produce video on the
screen.
D. DIGITAL CONTROLLOR:
With the EEPROM and PROGRAM, the micro-processor (u-P) control all the picture
performance.
From the key control, the user can change the H-size, V-size, V-center, H-phase.

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R B G 5V 5V
5V
12V
12V 80V
13.5V
12V12V
-12V
V-scan to DY
53V
Heater 6.3V
H.V. 25KV to CRT
Dynamic Focus to CRT
G2 Voltage 550V to CRT
-145V
13.3V
B++16V
B
+-
16V
B++16V
B
+-
16V
D/AOutput
from uP
LM1269 Video Pre-AMP UP WT62P1
NT6827
OSD generator
OSD DATA
EE-P-ROM 24C08
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
78R05
78R12
LM2467
Video Output AMP.
CRT & DY ASSY.
R
,
G
,
B out
TDA4856
H.V Sync Processor
TDA8172
Vertical Output AMP.
V-sawtooth
B
+
generator
H-Driver &
H-Scan Stage
FBT H.V generator
H-center
ADJ.
G1 ADJ.
Voltage generator
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