AOC CM-736 User manual

SERVICE MANUAL
M621
CM-736
17” MICRO CONTROLLED
COLOR MONITOR

THESE DOCUMENTS ARE FOR REPAIR SERVICE INFORMATION ONLY. EVERY REASONABLE
EFFORT HAS BEEN MADE TO ENSURE THE ACCURACY OF THIS MANUAL; WE CANNOT
GUARANTEE THE ACCURACY OF THIS INFORMATION AFTER THE DATE OF PUBLICATION
AND DISCLAIMS LIABILITY FOR CHANGES, ERRORS OR OMISSIONS.
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TABLE OF CONTENTS
PAGE
1. SPECIFICATIONS FOR CM-736 COLOR MONITOR
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3
2. PRECAUTION AND NOTICES .................................................................................... 4
2- 1 SAFETY PRECAUTIONS .................................................................................. 4
2-2PRODUCT SAFETY NOTICE 4 ............................................................................
2-3SERVICENOTES ............................................................................................
5
2-4HIGH VOLTAGE WARNING.............................................................................
5
3. OPERATION ......................................................................
6 ......................................
3- 1 OPERATION INSTRUCTIONS ...........................................................................
6
3-2 D-SUB/BNc
CONNECTOR...............................................................................
7
4. TIMING DIAGRAM &TABLE ..................................................................................... a
4- 1 EXTERNAL CONTROL..................................................................................... 8
4-2 DIGITAL FEATURES .......................................................................................
a
5.ADJUSTMENT 10 .........................................................................................................
5-l ADJUSTMENT CONDITIONS AND PRECAUTIONS .............................................10
5-2MAINADJUSTMENTS....................................................................................
10
5-3EXTERNAL CONTROLLED FUNCTION...............................................................
11
5-4 ALIGNMENT PROCEDURES.............................................................................
11
6.
PCB LAYOUT ........................................................................................................... 14
6- 1 MAINPCBLAYOUT....................................................................................... 14
6- 2 CRT PCB LAYOUT......................................................................................... 15
6-3 SMPS PCB LAYOUT....................................................................................... 15
6-4SIGNAL
PCB LAYOUT.................................................................................... 16
7. BLOCK
DIAGRAM (VIDEO VERT &HORI)...................................................................17
BLOCK DIAGRAM (SMPS)
.....................
...................................................................
la
8.TROUBLE
SHOOTINGG
............................................................................................... 19
8-
1 NoRASTER ............................19
......................................................................
8-2 ABNORMAL VIDEO ON CRT SCREEN .............................................................. 20
a-3ABNORMAL
WHITEE BALANCE.........................................................................20
8-44 NOBLANKINGWORK....................................................................................
21
a-5 H.OSC/DEF/HVV CIRCUITFAULT......................................................................
21
B-6F/v CONVERTERAND ASSOCIATEDCIRCUIT..................................................22
a-7UNSTABLE
SYNCHRONIZATION HORIZONTALL
.................................................22
8-8a POWERSUPPLY TROUBLESHOOTINGCHART.................................................23
9. MECHANICAL OF
CABlNET FRONT DIS-ASSEMBLY...................................................... 24
9- 1 MECHANICAL DIS-ASSEMBLY .......................................................................... 25
10 LOCATION OF ADJUSTMENT VR OF P.C.B................................................................ 26
11.PURITYADJUSTMENT
.............................................................................................
27
12. CONVERGENCE ADJUSTMENT
.
.....................................................
28 . .
............................
13.PARTSLISTING....................................................................................................... 29
14.SCHEMATICDIAGRAM............................................................................................ 53
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1. SPECIFICATIONS FOR CM-736 COLOR MONITOR
CRT:
DISPLAY:
INPUT
SIGNAL:
POWER
SOURCE:
OPERATING
CIRCUMSTANCE:
DIMENSIONS:
WEIGHT:
EXTERNAL
CONNECTION
Size:
Dot Pitch:
Screen:
Deflection:
Size:
Color Processing
Capability:
Resolution:
Video
Bandwidth:
Video Signal:
Sync. Signal
Type:
Power Supply:
Power
Comsumption:
Operating
Temperature:
Humidity:
Monitor:
Carton
:
Net (Gross):
Signal Line:
17-inch Diagonal F lat Square Type
0.26mm/0.28mm
Non-Glare Screen; anti-static; VLMF (OPTION)
90” Degree
(300± 10)mm X (225± 15)mm; External Adjustable
Unlimitted Color (Depend on Interface Card and Software Pro-
gram)
Up to 1280 X 1024
125
MHz/(-3 dB)
R.G.B. Analog 0.7 Vpp or 1.0 Vpp; 75 ohm
H.V. Seperated, TTL; or H.V. Composite, TTL; or Sync. on Green
0.3 Vpp (for Video 0.7 Vpp) and 0.43 Vpp (for Video 1 .O Vpp)
AC
9OV ~ 264V, 50Hz/60Hz, Auto-Range
130W Max.
5” to 40” Ambient
20% to 85% Relative, Non-Condensing
356(W) X 249(H) X 385(D) mm
455(W) X 450(H) X 460(D) mm
48.2 (52.8) Lbs
15 Pin D-type Connector or BNC Connector
For
SERVICES
Cherry Road,
Oxfordshire, OX9
351894
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2. PRECAUTIONS AND NOTICES
2-1
SAFETY PRECAUTIONS
1. Observe all caution and safety related notes located inside the display cabinet.
2. Operation of the display with the cover removed, may cause a serious, shock hazard from the
display power supply. Work on the display should not be attempted by anyone who is not
thoroughly familiar with precautions necessary when working on high voltage equipment.
3. Do not install, remove or handle the picture tube in any manner unless shatter-proof goggles are
worn. People who are not so equipped should be kept away while handling picture tube. Keep
picture tube away from the body while handling.
4. The picture tube is constructed to limit X-RAY radiation to 0.5
mR/HR. For continued
protection,use the designated replacement tube
only, and adjust the voltages so that the designat
-ed maximum rating at the anode will not be exceeded.
5. Before returning a serviced display to the customer, a thorough safety test must be performed
to verify that the display is safe to operate without danger or shock. Always perform an AC
leakage current check on the exposed metallic parts of the cabinet, such as screwheads. Test
method for current leakage is described as follow.
(a) Plug the AC line cord directly into rated AC outlet (do not use a line isolation transformer
during this check).
(b) Use an AC voltameter having 5000 ohms per volt or with more sensitivity in the following
manner
: Connect a 1500 ohms 10 Watt resistor, paralleled by a O.15mfd, AC type capacitor
between a known good earth ground (water pipe, conduit, etc.) and the exposed metallic
parts simultaneously. Measure the AC voltage across the combination of 1500 ohms
resistor and
0.15mfd capacitor.
(c) Reverse the AC plug at the AC outlet and repeat AC voltage measurements for each exposed
metal
lic part.
(d) Voltage measured must not exceed 2.8 volts RMS. This corresponds to 2 milliamp AC.
Any value exceeding this limit constitutes a potential shock hazard and must be corrected
immediately.
2-2 PRODUCT SAFETY NOTICE
Many electrical and mechanical parts in this chassis have special safety visual inspections and the
protection afforded by them cannot necessarily be obtained by using replacement components
rated for higher voltage, wattage, etc. Before replacing any of these components read the parts list
in this manual carefully. The use of substitute replacement parts which do not have the same safety
characteristics as specified in the parts list may create shock, fire, X-RAY radiation or other
hazards.
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2-3 SERVICE NOTES
1. When replacing parts or circuit boards, clamp the lead wires around terminals before soldering.
2. When replacing a high wattage resistor (more than
1W of metal oxide film resistor) in circuit
board, keep the resistor about 5mm away from circuit board.
3. Keep wires away from high voltage or high temperature components.
4. Keep wires in their original position so as to reduce interference.
2-4 HIGH VOLTAGE WARNING
Operation of monitor outside of cabinet or with back removed may cause a serious shock hazard,
Work on this modelshould only be performed by those who are thoroughly familiar with precautions
necessary when working on high voltage equipment.
Exercise care when servicing this chassis with power applied. Many
B plus and high voltage
terminals are exposed which, if carelessly contacted, can cause serious shock or result in damage to
the chassis, Maintain interconnecting ground lead connections between chassis and picture tube
dag when operating chassis.
Certain HV failures can increase X-ray radiation. Monitor should not be operated with HV levels
exceeding the specified rating for the chassis type. The maximum operating HV specified for the
chassis used in this monitor is
26KV± 1KV
with a line voltage of 120/24OV AC. Higher voltage may also increase possibility of failure in HV
supply.
It is important to maintain specified values of all components in the horizontal and high voltage
circuits and anywhere else in the monitor that could cause a rise in high voltage or operating supply
voltages.
No changes should be made to the original design of the monitor. Components shown in
the shaded areas on the schematic should be replaced with exact factory replacement parts. The use
of unauthorized substitute parts may create a shock, fire or other hazard.
To determine the presence of high voltage, use an accurate, high impedance, HV meter connected
between second anode lead and CRT dag grounding device. When servicing the High Voltage
System, remove static charge from it by connecting a
10K ohm resistor in series with an insulated
wire (such as a test probe) between picture tube dag and 2nd anode lead. (AC line cord disconnect-
ed from AC power outlet).
The picture tube used in this monitor employs integral implosion protection. Replace with tube
of the same type number for continued safety. Do not lift picture tube by the neck. Handle the
picture tube only after discharging the high voltage completely.
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3. OPERATION
3-l OPERATION INSTRUCTIONS
Follow these step-by-step instructions for proper monitor installation.
1. Be sure that the power switch is in the“Off” position before plugging in the power cord and
applying any AC power.
0
8
2.
3.
4.
5.
Cl
0 0
7
1
RGB ANALOG
INPUT INPUT LEVEL
0
2
AC SOCKET.
BNC
0.7V/l.OV INPUT LEVEL SWITCH.
Plug the power cord into the inlet socket after Step (1) has been verified. The diagram shown above
(rear view of exterior) shows proper hookup location of inlet socket (marked as
0 in the diagram).
Connect the signal cable terminals. One end to the monitor, the other end to the computer and/or
other signal source (Please don’t connect BNC type and D-SUB type cables simultaneously).
The input level
“0.7V” or ” 1 .OV” (marked as Q in the above diagram) is determined by the installed
display card. (Please refer to the Owner’s Manual of your display card).
After the above steps have been performed, you can now
position and enjoy your High Resolution Color Monitor. press your power switch to the “On”
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3-2 D-SUB/BNC CONNECTOR
A. D-SUB 15 PIN CONNECTOR
_a 0 uu2;;; i;;i; ;;u; 0
5 2 3 4 1
GND G B NC R 10 7 8 9 6
GND GND GND GND NC
B. BNC ANALOG SIGNAL
11 GND
12 NC
13 H.SYNC
14 V.SYNC
15 NC
BNC ANALOG INPUT
oooc;o
CONNECTOR
R
G/SYNC
SYNC, ON GREEN
RED
H/V SYNC ON
GREEN
COMPOSITE SYNC SEPARATE SYNC
RED RED
GREEN GREEN
B
BLUE BLUE BLUE
H/HV
-
H/V SYNC H-SYNC
V
--
V-SYNC
-
: means NO-CONNECTION
H : means HORIZONTAL
V: means VERTICAL
H/V : means COMPOSITE SYNC
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4. TIMING DIAGRAM & TABLE
4-l External control
SYMBOL
c
@
ITEM
1 POWER SWITCH
DESCRIPTION
- CONTROLS ON/OFF POWER TO THE
MONITOR
m
2 ON/OFF INDICATOR - LED (WHEN LIT) GIVES VISUAL
CONFIRMATION OF POWER ON
(>
3 CONTRAST
- ADJUSTS THE CHROMA CONTRAST
(INTENSITY) OF THE PICTURE
-a-
4 BRIGHTNESS
- ADJUSTS THE ILLUMINANCE OF THE
PICTURE
00
5 6 H-CENTER - ADJUSTS THE H-PHASE
(HORIZONTAL PLACEMENT) OF THE
PICTURE
me
7 8 H-SIZE - ADJUSTS THE H-SIZE (WIDTH) OF
THE PICTURE
8B
9 10 V-CENTER
- ADJUSTS THE V-PHASE (VERTICAL
PLACEMENT) OF THE PICTURE
mm 11 12 V-SIZE
- ADJUSTS THE V-SIZE (HEIGHT) OF
THE PICTURE
DEGAUSS 13
DEGAUSSING - IMPROVES AND MAINTAINS
OVERALL PICTURE PURITY
4-2 Digital Features
1.
2.
This monitor has adapted an advanced CPU to control the H-CENTER, the H-SIZE, the V-CENTER,
the V-SIZE, and it will auto memory the image features whenever the user changed them.
This monitor includes fourteen sets of factory preset timing (See the following table) and
twenty-
one sets of user’s new timing.
TIMING DIAGRAM
I
II
-_-I
H. VIDEO
I!
B
+ D< ,
1
I
H. SYNC
-tCL A
z
I
V. SYNC
A = HORI. SYNC. PERIOD.
B = HORI. ACTIVE TIME.
C = HORI. SYNC. WIDTH.
D = HORI. BACK PORCH.
E = VERT. SYNC. PERIOD.
F = VERT. ACTIVE TIME.
G = VERT. SYNC. WIDTH.
H = VERT. BACK PORCH.
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TIMING TABLE
MODE TIMING A (µS) B (µS) C (µS) D (µS) E (mS) F (mS) G (mS) H (mS) H-SYNC V-SYNC HORL
POLARITY POLARITY FREQUENCY
1. VGA 350 31.91625.42 3.813 1.76514.33 11.171 0.064 1.915 POSITIVENEGATIVE
31.47KHz
2. VGA 400 31.91625.42 3.813 1.76514.33 12.7660.064 1.117NEGATIVEPOSITIVE
31.47KHz
3. VGA 480 31.77625.421 3.813 1.74816.68215.2520.064 1.049NEGATIVENEGATIVE
31.47KHz
4. 800 x 600 ( -1 28.44422.2222.00 3.44417.77817.0660.057 0.626 xX
35.156KHz
8514A
5. INTERLACE 28.14622.8023.919 1.15811.49810.8080.113 0.563 xX
35.528KHz
UVGA
6. 640 x 400 26.41320.317 1.27
4.063 11.88610.5650.079 1.004NEGATIVEPOSITIVE
37.86KHz
UVGA
7. 640 x 350 26.41320.317 1.27 4.063 11.88610.5650.079 1.004 POSITIVENEGATIVE
37.86KHz
UVGA
8. 640 x 480 26.41320.317 1.27 4.003 11.88610.5650.079 1.004 POSITIVE POSITIVE
37.86KHz
9. 800 x 600 (=)I 26.40 20.00 3.20 2.10 16.57915.8400.106 0.634 xX
37.879KHz
10. 1024 x 768 20.66215.5422.06 2.521 16.65415.951 0.124 0.475 XX
48.399KHz
8514A
11. NON-INTERLACE 20.65115.6672.303 1.251 13.75412.4320.124 0.475 xX
48.432KHz
VESA
12. 17.70713.6531.813 1.92014.27213.5990.106 0.478 XX
56.476KHz
1024 4 768
13. 64K 15.68611.6201.489 1.99716.73716.0620.047 0.596 xX
63.750KHz
14. 75K 13.2929.846 1.815 0.769 14.22213.611 0.186 0.426 xX
75.23KHz
( x : Don’t care positive or negative)
3.
4.
When the new timing be traced, the CPU will auto memory it. And this monitor able to memory twenty-one
sets of new timing at the same time.
When twenty-one sets of new timing are full of the memory and the twenty-second new timing be input-
ted. The CPU will erase the first new timing which will be replaced by the twenty-second new timing, and
so on ,.. (that is say, this monitor can support unlimited new timings).
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