Samsung AN15VS, AN551V, AN551S Service Manual

COLOR MONITOR
Chassis Model AN15V* 551V, 551S
56V, 56E
Manual
SERVICE
COLOR MONITOR CONTENTS
1. Precautions
3. Disassembly & Reassembly
4. Alignment & Adjustments
5. Troubleshooting
6. Exploded View & Parts List
7. Electrical Parts List
8. Block Diagram
9. Wiring Diagram
10. Schematic Diagrams
CONFIDENTIAL
WARNINGS
1. For continued safety, do not attempt to modify the circuit board.
2. Disconnect the AC power before servicing.
3. When the chassis is operating, semiconductor heatsinks are potential shock hazards.
1-1-1 Servicing the High Voltage and CRT :
WARNING: A high voltage adjusted to the wrong
value may cause excessive X-ray emissions.
1. When servicing the high voltage system, remove the static charge by connecting a 10 kohm resistor in series with an insulated wire (such as a test probe) between the chassis and the anode lead.
2. When troubleshooting a monitor with excessively HV, avoid being unnecessarily close to the monitor. Do not operate the monitor for longer than is necessary to locate the cause of excessive voltage.
3. High voltage should always be kept at the rated value, no higher. Only when high voltage is excessive are X-rays capable of penetrating the shell of the CRT, including the lead in glass material. Operation at high voltages may also cause failure of the CRT or high voltage circuitry.
4. When the HV regulator is operating properly, there is no possibility of an X-ray problem. Make sure the HV does not exceed its specified value and that it is regulating correctly.
5. The CRT is especially designed to prohibit X-ray emissions. To ensure continued X-ray protection, replace the CRT only with one that is the same or equivalent type as the original.
6. Handle the CRT only when wearing shatterproof goggles and after completely discharging the high voltage anode.
7. Do not lift the CRT by the neck.
1-1-2 Fire and Shock Hazard :
Before returning the monitor to the user, perform the following safety checks:
1. Inspect each lead dress to make certain that the leads are not pinched or that hardware is not lodged between the chassis and other metal parts in the monitor.
2. Inspect all protective devices such as nonmetallic control knobs, insulating materials, cabinet backs, adjustment and compartment covers or shields, isolation resistor-capacitor networks, mechanical insulators, etc.
3. Leakage Current Hot Check (Figure 1-1):
WARNING: Do not use an isolation transformer during
this test.
Use a leakage current tester or a metering system that complies with American National Standards Institute (ANSI C101.1, Leakage Current for
Appliances), and Underwriters Laboratories (UL Publication UL1410, 59.7).
4. With the unit completely reassembled, plug the AC line cord directly into a 120V AC outlet. With the unit’s AC switch first in the ON position and then OFF, measure the current between a known earth ground (metal water pipe, conduit, etc.) and all exposed metal parts, including: metal cabinets, screwheads and control shafts. The current measured should not exceed 0.5 milliamp. Reverse the power-plug prongs in the AC outlet and repeat the test.
Figure 1-1. Leakage Current Test Circuit
1-1-3 Product Safety Notices
Some electrical and mechanical parts have special safety-related characteristics which are often not evident from visual inspection. The protection they give may not be obtained by replacing them with components rated for higher voltage, wattage, etc. Parts that have special safety characteristics are identified by
on schematics and parts lists. A substitute replacement that does not have the same safety characteristics as the recommended replacement part might create shock, fire and / or other hazards. Product safety is under review continuously and new instructions are issued whenever appropriate.
Components identified by on schematics and parts lists must be sealed by a soldering iron after replacement and adjustment.
AN15V* 1-1
1 Precautions
1-1 Safety Precautions
!
DEVICE UNDER TEST
TEST ALL
EXPOSED METAL
SURFACES
(READING SHOULD
NOT BE ABOVE 0.5mA)
LEAKAGE CURRENT
TESTER
2-WIRE CORD
ALSO TEST WITH
PLUG REVERSED (USING AC ADAPTER PLUG AS REQUIRED)
EARTH
GROUND
CONFIDENTIAL
1. Servicing precautions are printed on the cabinet, and should be followed closely.
2. Always unplug the unit’s AC power cord from the AC power source before attempting to: (a) remove or reinstall any component or assembly, (b) disconnect PCB plugs or connectors, (c) connect all test components in parallel with an electrolytic capacitor.
3. Some components are raised above the printed circuit board for safety. An insulation tube or tape is sometimes used. The internal wiring is sometimes clamped to prevent contact with thermally hot components. Reinstall all such elements to their original position.
4. After servicing, always check that the screws, components and wiring have been correctly reinstalled. Make sure that the area around the serviced part has not been damaged.
1. Immediately before handling any semiconductor components or assemblies, drain the electrostatic charge from your body by touching a known earth ground. Alternatively, wear a discharging wrist­strap device. To avoid a shock hazard, be sure to remove the wrist strap before applying power to the monitor.
2. After removing an ESD-equipped assembly, place it on a conductive surface such as aluminum foil to prevent accumulation of an electrostatic charge.
3. Do not use freon-propelled chemicals. These can generate electrical charges sufficient to damage ESDs.
4. Use only a grounded-tip soldering iron to solder or desolder ESDs.
5. Use only an anti-static solder removal device. Some solder removal devices not classified as “anti-static” can generate electrical charges sufficient to damage ESDs.
5. Check the insulation between the blades of the AC plug and accessible conductive parts (examples: metal panels, input terminals and earphone jacks).
6. Insulation Checking Procedure: Disconnect the power cord from the AC source and turn the power switch ON. Connect an insulation resistance meter (500 V) to the blades of the AC plug.
The insulation resistance between each blade of the AC plug and accessible conductive parts (see above) should be greater than 1 megohm.
7. Never defeat any of the +B voltage interlocks. Do not apply AC power to the unit (or any of its assemblies) unless all solid-state heat sinks are correctly installed.
8. Always connect a test instrument’s ground lead to the instrument chassis ground before connecting the positive lead; always remove the instrument’s ground lead last.
6. Do not remove a replacement ESD from its protective package until you are ready to install it. Most replacement ESDs are packaged with leads that are electrically shorted together by conductive foam, aluminum foil or other conductive materials.
7. Immediately before removing the protective material from the leads of a replacement ESD, touch the protective material to the chassis or circuit assembly into which the device will be installed.
Caution: Be sure no power is applied to the
chassis or circuit and observe all other safety precautions.
8. Minimize body motions when handling unpackaged replacement ESDs. Motions such as brushing clothes together, or lifting your foot from a carpeted floor can generate enough static electricity to damage an ESD.
9. Indicates ESDs on the Schematic Diagram in this manual.
1 Precautions
1-2 AN15V*
CONFIDENTIAL
1-3 Electrostatically Sensitive Devices (ESD) Precautions
Some semiconductor (solid state) devices can be easily damaged by static electricity. Such components are commonly called Electrostatically Sensitive Devices (ESD). Examples of typical ESD devices are integrated circuits and some field­effect transistors. The following techniques will reduce the incidence of component damage caused by static electricity.
1-2 Servicing Precautions
WARNING1: First read the “Safety Precautions” section of this manual. If unforeseen circumstances
create conflict between the servicing precautions and safety precautions, always
follow the safety precautions. WARNING2: A high voltage adjusted to the wrong value may cause excessive X-ray emissions. WARNING3: An electrolytic capacitor installed with the wrong polarity might explode.
AN15V* 2-1
2 Product Specifications
2-1 Specifications
Picture Tube: 15-Inch (38 cm): 13.8-inch (35 cm) viewable,
Full-square flat-face tube, 90˚ Deflection, Semi- tint, Non-glare, Invar shadow mask, Anti-static silica coating, 0.28 mm Dot pitch
Scanning Frequency Horizontal 30 KHz ~ 55 KHz (Automatic)
Vertical 50 Hz ~ 120 Hz (Automatic) Display Colors Unlimited colors Maximum Resolution Horizontal 1024 Dots
Vertical 768 Lines Input Video Signal Analog, 0.7 Vp-p positive at 75 , internally terminated Input Sync Signal Separate Sync : TTL level positive/negative Maximum Pixel Clock rate 65 MHz
Active Display Horizontal : 267 mm ± 4 mm, Vertical : 200 mm ± 4 mm Input Voltage AC 90 ~ 264 Volts, 60 Hz / 50 Hz ± 3 Hz Power Consumption 80 Watt (max) Dimensions (W x D x H)
With Base 14.01 x 14.92 x 14.54 Inches (356 x 379 x 369.5 mm) Weight (Net/Gross) 11.5 kg (25.35 lbs) / Standard : 13.3 kg (29.32 lbs), Special : 13.4 kg (29.54 lbs) Environmental Considerations Operating Temperature : 32°F ~ 104°F (0°C ~ 40°C)
Humidity : 10 % ~ 80 % Storage Temperature : –4°F ~ 113°F (–20°C ~ 45°C) Humidity : 5 % ~ 95 %
• Above models comply with SWEDAC (MPR II) recommendations for reduced electromagnetic fields.
• Designs and specifications are subject to change without prior notice.
Item
Description
CONFIDENTIAL
CONFIDENTIAL
2 Product Specifications
2-2 AN15V*
2-2 Pin Assignments
5
15
Figure 2-1. Male Type Figure 2-2. Male Type
Sync Type
Pin No.
Macintosh
Separate
1 2 3 4 5 6 7 8
9 10 11 12 13 14 15
Red Green Blue N-C GND (DDC Return) GND-R GND-G GND-B N-C GND-Sync./Self-Test N-C DDC Data H-Sync. V-Sync. DDC Clock
GND-R Red H/V Sync. Sense 0 Green GND-G Sense 1 Reserved Blue Sense 2 GND V-Sync. GND-B GND H-Sync.
2 Product Specifications
AN15V* 2-3
QRS
P
O
Video
Sync
Sync
Horizontal
Vertical
CDE
P
O
B
A
Video
Sync
Sync
Separate Sync
2-3 Timing Chart
This section of the service manual describes the timing that the computer industry recognizes as standard for computer-generated video signals.
C D
A
O
E
B
P
Video
Sync
Sync
Video
Q R S
A : Line time total B : Horizontal sync width O : Frame time total P : Vertical sync width C : Back porch D : Active time Q : Back porch R : Active time E : Front porch S : Front porch
fH (kHz) A µsec B µsec C µsec D µsec E µsec fV (Hz) O msec P msec Q msec R msec S msec Clock
Frequency (MHz)
Polarity H.Sync
V.Sync Remark
IBM VESA
800/85 Hz 800 x 600
VGA3/60 Hz
640 x 480
VGA2/70 Hz
720 x 400
31.469
31.778
3.813
1.907
25.422
0.636
70.087
14.268
0.064
1.080
12.711
0.413
28.322
Negative
Positive
Separate
31.469
31.778
3.813
1.907
25.422
0.636
59.940
16.683
0.064
1.048
15.253
0.318
25.175
Negative Negative Separate
43.269
23.111
1.556
2.222
17.778
1.556
85.008
11.764
0.671
0.578
11.093
0.023
36.000
Negative Negative Separate
53.674
18.631
1.138
2.702
14.222
0.569
85.061
11.756
0.056
0.503
11.179
0.019
56.250
Positive Positive
Separate
640/85 Hz 640 x 480
Table 2-1 Timing Chart
Mode
Timing
37.500
26.667
2.032
3.810
20.317
0.508
75.000
13.333
0.080
0.427
12.800
0.027
31.500
Negative Negative Separate
640/75 Hz 640 x 480
CONFIDENTIAL
CONFIDENTIAL
2 Product Specifications
2-4 AN15V*
Memo
3-1-1 Before making Disassembly
1. Disconnect or power cord from the monitor.
2. With a pad beneath it, stand the monitor on its front with the screen facing downward and the base close to you.
3-1-2 Cabinet Disassembly
1. Remove the Stand from the monitor. (Refer to Stand manual)
2. Remove 2 screws on the Rear cover.
3. Incline the monitor by lifting the rear of the monitor.
4. Push the Opening jig each groove along the top of the monitor till it makes a “ttak” sound. (2 grooves : Left and Right, Make sure each snap is disengaged.)
5. Pull the Rear Cover up off the monitor.
AN15V* 3-1
3 Disassembly and Reassembly
This section of the service manual describes the disassembly and reassembly procedures for the AN15V* monitor.
WARNING: This monitor contains electrostatically sensitive devices. Use with caution when
handling these components.
3-1 Disassembly
Cautions: 1. Disconnect the monitor from the power source before disassembly.
2. To remove the Rear Cover, you must use the special opening jig tool.
Figure 1
Figure 2
Figure 3
Figure 4
CONFIDENTIAL
6. Remove the Shield.(TCO 95)
7. Using pinch-nose pliers or ling-nose pliers, acrefully disconnect the Anode Cap from the CRT.
Warning: Do not touch the Anode contact
on the CRT (High Voltage may remain).
3-1-3 Removing the CRT Socket PCB
1. Complete all previous steps.
2. Lift up the Video Spring and remove the CRT Socket PCB from the CRT.
3. Disconnect all connectors on the CRT Socket PCB.
4. Using a solder iron, disconnect Ground (GND) on the back of the Video Shield and remove the Shield Cap.
5. Remove the screw on the front of the Shield Socket.
6. Desolder the 4 tabs on the CRT Socket PCB and remove Shield.
7. Place the Video PCB on a flat, level surface that is protected from static electricity.
3-1-4 Removing the Main PCB
1. Complete all previous steps.
2. Disconnect the Degaussing Coil at CN603 on the Main PCB.
3. Disconnect all easily accessible ground wires on the PCB and Bottom Chassis.
4. Disconnect the DY connector at the CN404 connector on the Main .
5. Using the jig, release the snaps (2) connecting the Front Cover and the PCB then lift up the Bottom to separate the two Shield.
6. Disconnect the Sub PCB connector at the CN201 connector on the Main PCB.
7. Remove the screws on the back and along each side of the Bottom Chassis.
8. Carefully lift the Main PCB Assy and remove the remaining ground wires.
9. Place the Main PCB Assy on a flat, level surface that is protected from static electricity.
3-1-5 CRT Ass’y Disassembly
1. Complete all previous steps.
2. Straighten the Degaussing Coil Assembly coated metal ties and lift the Coil Assy from the CRT.
3. Remove the four corner screws and lift the CRT up and away from the Front Cover Assembly and place it on a padded surface.
Caution: Do not lift the CRT by the neck.
If you will be returning this CRT to the monitor, be sure to place the CRT face downward on a protective pad.
3 Disassembly and Reassembly
3-2 AN15V*
CONFIDENTIAL
3-2 Reassembly
Reassembly procedures are in the reverse order of Disassembly procedures.
Figure 6
Figure 7
Figure 5
4-1-1 Before Making Adjustments
4-1-1 (a) ORIENTATION
When servicing, always face the monitor to the east.
4-1-1 (b) WARM-UP TIME
The monitor must be on for 30 minutes before starting alignment. Warm-up time is especially critical in color temperature and white balance adjustments.
4-1-1 (c) SIGNAL
Analog, 0.7 Vp-p positive at 75 ohm, internal termination Sync: TTL level, negative/positive
4-1-1 (d) SCANNING FREQUENCY
Horizontal: 30 KHz ~ 55 KHz (Automatic) Vertical: 50 Hz ~ 120 Hz (Automatic)
Unless otherwise specified, adjust at the 800 x 600 mode (54 KHz/85 Hz).
4-1-2 Required Equipment
The following equipment may be necessary for adjustment procedures:
4-1-2 (a) DISPLAY CONTROL ADJUSTMENT
1. Non-metallic (–) screwdriver:
1.5, 2.5, 3 mm
2. Non-metallic (+) screwdriver:
1.5, 2.5, 3 mm
3. Digital Multimeter (DMM), or Digital Voltmeter
4. Signal generator, or DM200 software
5. Personal computer
4-1-2 (b) COLOR ADJUSTMENTS
1. All equipment listed in 4-1-2 (a), above
2. Color analyzer, or any luminance measurement equipment
AN15V* 4-1
4 Alignment and Adjustments
This section of the service manual explains how to make permanent adjustments to the monitor. Directions are given for adjustments using the monitor Interface Board Ver. 1.1 and software (Softjig).
4-1 Adjustment Conditions
Caution: Changes made without the Softjig are saved only to the user mode settings. As such, the
settings are not permanently stored and may be inadvertently deleted by the user.
CONFIDENTIAL
4 Alignment and Adjustments
4-2 AN15V*
CONFIDENTIAL
4-2-1
HIGH VOLTAGE
Signal: 800 x 600 (54 KHz/85 Hz) Display image: Full White Pattern Contrast: Maximum Brightness: Maximum Limit: 25.0 kV ± 0.2 kV
Measure the hight voltage level at the anode cap. High voltage should be within the limit as above.
4-2-2 CENTER RASTER
Adjust VR401 so that the back raster comes to the center when you apply each basic mode.
SCREEN VOLTAGE ADJUSTMENT
This can only SDI CRT conditions. Signal: 800 x 600 (54 KHz/85 Hz) Display image: Dont care Contrast: Minimum Brightness: Minimum Limit: 480 ± 10V
Adjust screen VR of T501.
4-2-3 Centering
Centering means to position the center point of the display in the middle of the display area. Horizontal size and position and vertical size and position control the centering of the display.
Adjust the horizontal size and vertical size to their optimal settings: 267 mm (H) x 200 mm.
Adjust the horizontal position and vertical position to 5.0 mm of the center point of the screen.
|A – B| 5.0 mm. |C – D| 5.0 mm.
Figure 4-3. Centering
4-2-3 (a-1) HORIZONTAL SIZE ADJUSTMENT CONDITIONS
Scanning frequency: 54 KHz/85 Hz Display image: Crosshatch pattern Brightness: Maximum Contrast: Maximum
Use control bar after selecting SIZE B+ in left menu to adjust the horizontal size of the display pattern to 255 mm . (Tolerance: ± 4 mm.)
4-2-3 (a-2) HORIZONTAL SIZE ADJUSTMENT
Use control bar after selecting H-SIZE in left menu to adjust the horizontal size of the display pattern to 267 mm . (Tolerance: ± 4 mm.)
4-2-3 (b) VERTICAL SIZE ADJUSTMENT CONDITIONS
Scanning frequency: 54 KHz/85 Hz Display image: Crosshatch pattern Brightness: Maximum Contrast: Maximum
Use control bar after selecting “V-SIZE” in left menu to adjust the vertical size of the display pattern to 200 mm. (Tolerance: ± 4 mm.)
4-2-3 (c) HORIZONTAL POSITION ADJUSTMENT CONDITIONS
Scanning frequency: 54 KHz/85 Hz Display image: Crosshatch pattern
Use control bar after selecting H-POSITION in left menu to center the horizontal image on the raster.
4-2-3 (d) VERTICAL POSITION ADJUSTMENT CONDITIONS
Scanning frequency: 54 KHz/85 Hz Display image: Crosshatch pattern
Use control bar after selecting V-POSITION in left menu to center the vertical image on the raster.
4-2-4 Linearity
Linearity affects the symmetry of images as they appear on the screen. Unless each row or column of blocks in a crosshatch pattern is of equal size, or within the tolerances shown in Table 4-1 an image appears distorted, elongated or squashed.
Horizontal Linearity = 2x x100
Vertical Linearity = 2x x100
Table 4-1
Preset Mode : 54KHz / 85Hz
Pre-load Mode : Refer to Timing Chart
4-2 Display Control Adjustments
C
A
DISPLAY AREA
EDGE OF BEZEL
B
D
X max-X min
X max+X min Y max-Y min Y max+Y min
Preset mode ≤ 4% ≤ 8%
Adjacent Linearity
Entire Linearity
Pre-load mode (48kHz~) ≤ 5% ≤ 14%
4-2-4 (a) HORIZONTAL LINEARITY ADJUSTMENT CONDITIONS
Scanning frequency: 54 KHz/85 Hz Display image: Crosshatch pattern Brightness: Maximum Contrast: Maximum
To adjust the Horizontal Linearity, refer to Table 4-1 for the tolerance range.
Increase or decrease H_LIN to optimize the image.
4-2-4 (b) VERTICAL LINEARITY ADJUSTMENT CONDITIONS
Scanning frequency: 54 KHz/85 Hz Display image: Crosshatch pattern Brightness: Maximum Contrast: Maximum
To adjust the Vertical Linearity, refer to Table 4-1 for the tolerance range.
Use control bar after selecting V-LINEARITY BAL” in left menu to optimize the image.
4-2-5 Trapezoid Adjustment
CONDITIONS
Scanning frequency: 54 KHz/85 Hz Display image: Crosshatch pattern Brightness: Maximum Contrast: Maximum
Use control bar after selecting TRAPEZOID in left menu to make the image area rectangular.
Figure 4-4. Trapezoid
4-2-6 Pinbalance Adjustment
CONDITIONS
Scanning frequency: 54 KHz/85 Hz Display image: Crosshatch pattern Brightness: Maximum Contrast: Maximum
Use control bar after selecting PINBALANCE in left menu to optimize the image.
4-2-7 Parallelogram Adjustment
CONDITIONS
Scanning Frequency: 54 KHz/85 Hz Display image: Crosshatch pattern Brightness: Maximum Contrast: Maximum
Use control bar after selecting PARALLEL in left menu to make the image area rectangular.
Figure 4-6. Parallelogram
4-2-8 Side Pincushion Adjustment
CONDITIONS
Scanning frequency: 54 KHz/85 Hz Display image: Crosshatch pattern
Use control bar after selecting PINCUSHION in left menu to straighten the sides of the image area.
4-2-9 Degauss
No adjustments are available for the degaussing circuit. The degaussing circuit can effectively function only once per 30 minutes.
4-2-10 To Delete the User Mode Data
To delete the adjustment data from the user modes, click @4: USER DELETEin right ment.
4-2-11 Save the Data
To save the adjustment data for a mode, press @3: ALL MODE SAVE in right ment.
4 Alignment and Adjustments
AN15V* 4-3
CONFIDENTIAL
| A – B | < 4 mm
A
B
B
A
D1 D2 D1
Figure 4-5. Pinbalance
| D1 |, | D2 | 2.0 mm
4 mm
Figure 4-7. Pincushion
| C1 |, | C2 | 2.0 mm, | D1 |, | D2 | 2.0 mm.
D1
C2
D2
C1
4 Alignment and Adjustments
4-4 AN15V*
CONFIDENTIAL
CAUTION : Check below condition before color
adjustment Video signal : Analog 0.7 Vp-p (at 75 Ω) Sync : TTL level (H, V seperate signal)
* Select Color in Softjig menu for color adjustment.
4-3-1 Color Coordinates (Temperature)
Color temperature is a measurement of the radiant energy transmitted by a color. For computer monitors, the color temperature refers to the radiant energy transmitted by white. Color coordinates are the X and Y coordinates on the chromaticity diagram of wavelengths for the visible spectrum.
CONDITIONS
Measurement instrument: Color analyzer Scanning frequency: 54 KHz/85 Hz Display image: White flat field at
center of display area
Luminance: Maximum
PROCEDURE
Use the directions in sections 4-3-2 through 4-3-3 to adjust the color coordinates for: 9300K to x = 0.283 ± 0.015, y = 0.298 ± 0.015 6500K to x = 0.313 ± 0.015, y = 0.329 ± 0.015
4-3-2 Color Adjustments for 9300K
4-3-2 (a) BACK RASTER COLOR ADJUSTMENT CONDITIONS
Scanning frequency: 54 KHz/85 Hz Display image: Back raster pattern Brightness: Maximum Contrast: Maximum
1. Select @1: CHANNEL 1in right menu to
control the color for 9300K.
2. Adjust the luminance of the back raster to between 0.5 to 0.7 ft-L using contron bar after selecting GREEN CUTOFFin the menu.
3. Use control bar after selecting BLUE CUTOFF in left menu to set the “y coordinate to 0.298 ± 0.015
4. Use control bar after selecting RED CUTOFFin left menu to 0.283 ± 0.015
* If color values would not be matched desirable
values, repeat sequence 3 and 4 after readjusting GREEN CUTOFF control a little different.
4-3-2 (b) WHITE BALANCE ADJUSTMENT CONDITIONS
Scanning frequency: 54 KHz/85 Hz Display image: White box pattern Brightness: 0.06ft-L at Back Raster
Pattern Display
Contrast: Maximum
1. Use control bar after selecting RED GAIN”, GREEN GAIN and BLUE GAINto adjust the luminance to 50 ft-L with the color coordinates ranged for 9300K to x = 0.283 ± 0.015, y = 0.298 ± 0.015.
Figure 4-8. White Box Pattern
4-3-2 (c) ABL ADJUSTMENT CONDITIONS
Scanning frequency: 54 KHz/85 Hz Display image: Full white pattern Brightness: Maximum Contrast: Maximum
Figure 4-9. Full White Pattern
1. Check the ABL. If it is not within the
specifications, use the ABL controls to adjust it. (38 ± 1 ft-L )
2. Select @4: COLOR SAVEto save the data.
3. Select @6: ALL COLOR SAVEto save the
CH2.
4-3-2 (d) WHITE BALANCE ADJUSTMENT VERIFICATION CONDITIONS
Scanning frequency: 54 KHz/85 Hz
1/3H-1/2H
1/3V-1/2V
FRONT BEZEL OPENING BACK RASTER
WHITE WINDOW
FRONT BEZEL OPENING BACK RASTER
WHITE WINDOW
4-3 Color Adjustments
4 Alignment and Adjustments
AN15V* 4-5
CONFIDENTIAL
Display image: Back raster pattern
Full White Pattern
X-Y Coordinates: x = 0.283 ± 0.015,
y = 0.298 ± 0.015 ABL Luminance Refer to 4-3-2(c) Brightness: Maximum Contrast: 5 ft-L, 24 ft-L
1. Check whether the color coordinates of the
back raster satisfy the above spec. If they do not, return to 4-3-2 (a) and readjust
all settings.
2. Display a full white pattern.
3. Select Geometry in softjig menu.
4. Select @7: 5-ft in right menu.
5. Check whether the white coordinates of the
video meet the above coordinates spec.
6. Select @8: 24-ft in right menu.
7. Check whether the white coordinates of the
video satisfies the above spec. If they do not, return to 4-3-2 (a) and readjust
all settings. Select Color and click @2: CHANNEL 2
for color ajdustment for 6500K Repeat the sequence of 9300K adjustment. The luminance values the same as 9300K, but the color coordinated of back raster and white box are : x = 0.313 ± 0.015 y = 0.329 ± 0.015
4-3-3 Luminance Uniformity Check
Luminance is considered uniform only if the ratio of lowest to highest brightness areas on the screen is not less than 7.5:10.
CONDITIONS
Scanning frequency: 54 KHz/85 Hz
(800 x 600) Display image: White flat field Brightness: Cut off point at 24 ft-L Contrast: Maximum
PROCEDURE
Measure luminance at nine points on the display screen (see figure below).
4-3-4 Focus Adjustment
CONDITIONS
Scanning frequency: 54 KHz/85 Hz
(800 x 600) Display image: “H” character pattern Brightness: Cut off point Contrast: Maximum
PROCEDURE
1. Adjust the Focus VR on the FBT to display the
sharpest image possible.
2. Use Locktite to seal the Focus VR in position.
4-3-5 Color Purity Adjustment
Color purity is the absence of undesired color. Conspicuous mislanding (unexpected color in a uniform field) within the display area shall not be visible at a distance of 50 cm from the CRT surface.
CONDITIONS
Orientation: Monitor facing east Scanning frequency: 54 KHz/85 Hz Display image: White flat field Luminance: Cut off point at the center
of the display area Note: Color purity adjustments should only be
attempted by qualified personnel.
PROCEDURE
For trained and experienced service technicians only.
Use the following procedure to correct minor color purity problems:
1. Make sure the display is not affected by
external magnetic fields.
2. Make sure the spacing between the PCM
assembly and the CRT stem is 29 mm ± 1 mm.
3. Display a green pattern over the entire display
area.
4. Adjust the purity magnet rings on the PCM
assembly to display a pure green pattern. (Optimum setting: x = 0.295 ± 0.015, y = 0.594 ± 0.015)
Table 4-2. Color Purity Tolerances
(For 9300K color adjustment: x = 0.283 ± 0.015, y = 0.298 ± 0.015)
5. When you have the PCMs properly adjusted,
carefully glue them together to prevent their movement during shipping.
Figure 4-10. Luminance Uniformity Check Locations
Red: x = 0.640 ± 0.015 y = 0.323 ± 0.015 Green: x = 0.295 ± 0.015 y = 0.594 ± 0.015 Blue: x = 0.142 ± 0.015 y = 0.066 ± 0.015
Memo
4 Alignment and Adjustments
4-6 AN15V*
CONFIDENTIAL
CONFIDENTIAL
AN15V* 5-1
5 Troubleshooting
5-1 Parts Level Troubleshooting
Notes: Check the following circuits.
• No raster appears: Power circuit, Horizontal output circuit.
• High voltage develops but no raster appears: Video output circuits.
• High voltage does not develop: Horizontal output circuits.
5-1-1 No Power Supply
Chirping noise exists?
Check and replace IC601.
Check and replace D601 and FH_1.
Done.
No
Yes
Repeating start?
Check and replace D606.
No
Yes
IC601 Pin 1 waveform is right?
Check and replace Q602, IC605,
OP202 and IC602.
Yes
No
C622 Voltage is 13 V ± 0.5V?
Check and replace IC201, IC301,
IC401, IC605, Q402,
Q404, Q613,and Q614.
Yes
No
Operate normally?
Replace Main board.
Yes
Verify voltages.
No
1
WAVEFORMS
1
100 V (IC601, #1)
CH1 P-P = 100 V CH1 RMS = 350.2 V
CONFIDENTIAL
5 Troubleshooting
5-2 AN15V*
5-1-2 DPMS Failure
Make No H/V Sync.
(power off mode)
Check signal source
H/V Sync. video level.
LED blinks?
Check IC201 Pin 40.
Yes
No
+12 V line off?
Check IC201 Pin 5, Pin 6 and Q610,
Q602 operation condition.
Yes
No
Q602 Base
voltage exists?
Refer to 5-1-1 No Power Supply.
Done
Yes
No
IC601 Pin 1 Output
voltage exists?
Check IC201 Pin 5.
Check and replace Q602 and IC201.
No
2
WAVEFORMS
2
100 V (IC601, #1)
CH1 P-P = 100 V CH1 RMS = 325.8 V
CONFIDENTIAL
5 Troubleshooting
AN15V* 5-3
5-1-3 H_Deflection Failure
Does Horizontal pluse signal
appear at at Pin 26 of IC605?
Check IC605.
Yes
No
Does 20 Vp-p signal appear
at Collector of Q400?
Check Q400.
Yes
No
Check D406, Q404 and T401.
4
Does PWM output signal appear
at Pin 28 (B_drv) of IC605?
Check IC605.
Check 12 V line.
Yes
No
Does DC 12V appear at
Pin 29 of IC605?
Yes
No
3
5-1-4 S Correction Failure
S1~S2 signals are right at each
frequency block?
Check S1 ~ S2 signal.
Check and replace
Q404, Q410, Q411, Q415, and Q416.
Yes
Check and replace IC201.
No
5
WAVEFORMS
3
5.00 V (IC605, #28)
4
1.00 V (IC605, #26)
5
5.00 V (Q400, Collector)
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