SAMSUNG CSH7839TXAA Service Manual

Manual

SERVICE

COLOR MONITOR CONTENTS

1. Precautions

2. Reference Information

3. Product Specifications

4. Operating Instructions

5. Disassembly & Reassembly

6. Alignment & Adjustments

7. Troubleshooting

8. Exploded View & Parts List

9. Electrical Parts List

10. Block Diagram

11. PCB Diagrams

12. Wiring Diagram

13. Schematic Diagrams

COLOR MONITOR

CSH7839L (SyncMaster 700p )

CSH9839L (SyncMaster 900p)

Samsung Electronics Co., Ltd. April 1998. Printed in Korea Code No.: BH68-61072A

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 VR

and CRT :

WARNING: A high voltage VR replaced in the wrong

direction may cause excessive X-ray emissions.

Caution:

When replacing the high voltage adjustment VR, it must be fixed by a soldering iron after it is properly set.

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. If the HV VR requires adjustment, (a) Replace the VR and adjust the high voltage to the specification. (b) Use a soldering iron to melt the adjustment cap on the HV VR to prevent any movement.

3. 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.

4. 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.

5. 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.

6. 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.

7. Handle the CRT only when wearing shatterproof goggles and after completely discharging the high voltage anode.

8. 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

1-1-4 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.

CSH7839L/CSH9839L 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

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 CSH7839L/CSH9839L

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 VR replaced in the wrong direction may cause excessive X-ray

emissions.

WARNING3: An electrolytic capacitor installed with the wrong polarity might explode.

CSH7839L/CSH9839L 2-1

2 Reference Information

2-1 List of Abbreviations, Symbols and Acronyms

2-1-1 Abbreviations

Abbreviation Definition Abbreviation Definition

ASS’Y Assembly B Blue B+ ADJ B+ Adjustment B-CUT Blue-Cutoff B-GAIN Blue Gain BRIGHT Brightness C R-Composition C-MIC Condenser Microphone CLK Clock CM R-Cement CN Connector CONT Contrast D-SUB D-Subminiature EEP-CLK Electrically Erasable and

Programmable Clock EXT External EXT-MIC External Microphone Freq. Frequency FU Fusible G Green G-CUT Green-Cutoff G-GAIN Green Gain GND Ground H Horizontal H Heater H-DRV Horizontal Drive H-DY Horizontal Deflection Yoke H-FLB Horizontal Flyback H-FV Horizontal-Feedback Voltage H-LIN Horizontal Linearity H-POSI Horizontal Position H-SIZE Horizontal Size H/PHONE Headphone Hz Hertz I-SENSE Current-Sense lb Pound MAX Maximum MIC Microphone MIN Minimum MP C-Metalized Polyester MPP Metal Polypropylene MO R-Metal Oxide

OSC Oscillator P C-Polyester PARA Parabola PARALL Parallelogram PIN-BAL Pincushion Balance PRE-AMP Pre-Amplifier PS1 Power Saving1 (suspend) PS2 Power Saving2 (off) PWR Power R Red R-CUT Red-Cutoff R-GAIN Red Gain RST Reset S-PIN Side Pincushion S-RASTER Self Raster S/W Switch SCAP S Correction Capacitor SPK Speaker SYNC Synchronization T C-Tantalum TR Transistor TRAP Trapezoid U-COM Microprocessor V Vertical V-DY Vertical Deflection Yoke V-FLB Vertical Flyback V-LIN Vertical Linearity V-MUTE Video Mute V-OUT Vertical Output V-PARA Vertical Parabola V-POL V-Polarity V-POSI Vertical Position V-SENSE Voltage-Sense V-SIZE Vertical Size WW R-Wire Wound X-TAL Crystal Ω ohm KΩ 1000 ohm MΩ 1000 KΩ uF microfarad (10-6F) nF nanofarad (10-9F) pF picofarad (10

-12

2 Reference Information

2-2 CSH7839L/CSH9839L

Acronym Definition Acronym Definition

ABL Automatic Brightness Limits AC Alternating Current ACL Automatic Contrast Limit AFC Automatic Frequency Control ANSI American National Standards Institute CMOS Complementary Metal Oxide

Semiconductor CRT Cathode Ray Tube DC Direct Current DDC Data Display Channel DF Dynamic Focus DMM Digital Multimeter DPMS Display Power Management Signaling DVM Digital Voltmeter DY Deflection Yoke EEPROM Electrically Erasable and

Programmable Read only Memory ESD Electrostatically Sensitive Device ESF Electronic Static Field FBT Flyback Transformer FET Field Effect Transistor FH Horizontal Frequency FS Fail Safe FV Vertical Frequency GD Geometric Distortion

H/V Horizontal/Vertical HV High Voltage I/O Input/Output IC Integrated Circuit LED Light Emitting Diode MAC Macintosh MOFA Mask Outside Frame Assembly OCP Over Current Protection OP AMP Operational Amplifier OSD On Screen Display P-P Peak to Peak PCB Printed Circuit Board PLL Phase Locked Loop PWM Pulse Width Modulation SMPS Switch Mode Power Supply SVGA Super Video Graphics Array SWEDAC TP Test Point UL Underwriters Laboratories USB Universal Serial Bus VESA Video Electronics Standard

Association VGA Video Graphics Array VR Variable Registor W/B White Balance

2-1-2 Acronyms

2-1-2 Symbols

Can emit X-radiation Hot Ground Cold Ground Electrostatically Sensitive Device (ESD) Provides special safety considerations

3 Product Specifications

3-1 Specifications

Picture Tube: 19-Inch (48.2 cm): 18-inch (45.7 cm) viewable, 17-Inch (43 cm): 16.0-inch (40.6 cm) viewable,

0.26 mm Dot pitch, Full-square flat-face tube, 90˚ Deflection, Anti-Reflection coating with Anti-electrastatic, Medium short persistence phosphor

Scanning Frequency Horizontal : 30 kHz to 96 kHz (Automatic)

Vertical : 50 Hz to 160 Hz (Automatic) Display Colors Unlimited colors Maximum Resolution Horizontal : 1600 Dots

Vertical : 1200 Lines Input Video Signal Analog, 0.714 Vp-p positive at 75 Ω, internally terminated Input Sync Signal Separate Sync : TTL level positive/negative

Composite Sync : TTL level positive/negative

Sync-on-Green : Composite sync 0.286 Vp-p ± 5%/negative (Video on Vp-p positive) Maximum Pixel Clock rate 205 MHz Active Display CSH9839L; Horizontal : 352 mm ± 3 mm (4:3 ratio) / 330 mm ± 3 mm (5:4 ratio)

Vertical : 264 mm ± 3 mm

CSH7839L; Horizontal : 306 mm ± 3 mm (4:3 ratio)

Vertical : 230 mm ± 3 mm Input Voltage AC 90 to 264 Volts, 60/ 50 Hz ± 3 Hz Power Consumption 130 Watt (max) Dimensions CSH7839L CSH9839L

Unit (W x D x H) 16.3x17.5x17.2 Inches (415 x 445.7 x 437.3 mm) 18.4x19.6x19 Inches (468 x 499 x 483.2 mm) Carton (W x D x H) 21x22.3x21.6 Inches (535 x 566 x 549 mm) 22.6x23.2x22.8 Inches (573 x 590 x 580 mm)

Weight (Net/Gross) CSH9839L; 49.6 lbs (22.5 kg) / 58.8 lbs (26.7 kg)

CSH7839L; 40.8 lbs (18.5 kg) / 49.6 lbs (22.5 kg)

Environmental Considerations Operating Temperature : 32°F to 104°F (0°C to 40°C)

Humidity : 10 % to 80 % Storage Temperature : -4°F to 113°F (-20°C to 45°C)

Humidity : 5 % to 95 %

• CSH7839L/CSH9839L complies with SWEDAC (MPR II) recommendations for reduced electromagnetic fields.

• Designs and specifications are subject to change without prior notice.

CSH7839L/CSH9839L 3-1

Item Description

3 Product Specifications

3-2 CSH7839L/CSH9839L

3-2 Pin Assignments

Figure 3-1. Male Type Figure 3-2. Male Type

Sync Type

Pin No.

15-Pin Signal Cable Connector (Figure 3-1)

Cable Adapter (Figure 3-2)

Macintosh

Separate Composite

1 2 3 4 5 6 7 8

9 10 11 12 13 14 15

Red Green Blue GND DDC Return GND-R GND-G GND-B Reserved GND-Sync/Self-raster GND DDC Data H-Sync V-Sync DDC Clock

Red Green Blue GND DDC Return GND-R GND-G GND-B Reserved GND-Sync/Self-raster GND DDC Data H/V-Sync Not Used 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

BNC Connectors

BNC connectors are used with coaxial cable for improved signal transmission. Better signal transmission becomes critical at high frequencies, such as those required for 1280 x 1024 resolution. Most video boards that operate at 1280 x 1024 resolution recommend using coaxial cable with BNC connectors. The 5 BNC connectors on the rear of the monitor can accept Red, Green and Blue video. Composite sync can be applied separately, or combined with the Green video signal (commonly referred to as “composite sync-on green”). If composite sync-on-green is used, then only 3 of the 5 BNC connectors are used. The connectors are labeled accordingly.

Assignment

Signals

Sync-on-Green Composite Sync Separate Sync

Red

Green + Sync

Blue

NC NC

1 2 3 4 5

Red

Green

Blue

H/V Comp. Sync

Red

Green

Blue H-Sync V-Sync

RGB

H/V V

2 3

Figure 3-3. BNC Signal Input Type

3 Product Specifications

CSH7839L/CSH9839L 3-3

800/85 Hz 800 x 600

1280/85 Hz

1280 x 1024

640/85 Hz 640 x 480

VGA3/60 Hz

640 x 480

VGA2/70 Hz

720 x 400

QRS

Video

Sync

Horizontal

Vertical

CDE

Video

Sync

Separate Sync

Table 3-1. Timing Chart (CSH7839L)

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

Freq. (MHz)

Polarity H.Sync

V.Sync Remark

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

3.810

5.222

17.778

85.008

13.333

0.080

0.427

12.800

0.027

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

91.146

10.971

1.016

1.422

8.127

0.406

85.024

11.761

0.033

0.483

11.235

0.011

157.500

Positive Positive

Separate

Mode

IBM VESA MAC.

Timing

3-3 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

Video

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

VIDEO

Horizontal

Vertical

H/V Composite Sync

Sync-on-Green

60.023

16.660

1.219

2.235

13.003

0.203

75.029

13.328

0.050

0.466

12.795

0.017

78.750

Positive Positive

Separate

68.677

14.561

1.016

2.201

10.836

0.508

84.997

11.765

0.044

0.524

11.183

0.015

94.500

Positive Positive

Separate

49.726

20.110

1.117

3.910

14.524

0.559

74.551

13.414

0.060

0.784

12.549

0.020

57.284

Negative Negative

SOG

79.976

12.504

1.067

1.837

9.481

0.119

75.025

13.329

0.038

0.475

12.804

0.013

135.000

Positive Positive

Separate

81.400

12.285

0.988

1.624

9.037

0.635

100.000

10.000

0.037

0.516

9.435

0.012

113.309

Negative

Positive

Separate

1024/75 Hz 1024 x 768

1024/85 Hz 1024 x 768

832/75 Hz

832 x 624

1024/100 Hz

1024 x 768

1280/75 Hz

1280 x 1024

Green

Horizontal

Vertical

3 Product Specifications

3-4 CSH7839L/CSH9839L

Q R S

Video

Sync

Horizontal

Vertical

C D E

Video

Sync

Separate Sync

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

VIDEO

Horizontal

Vertical

H/V Composite Sync

Sync-on-Green

800/85 Hz 800 x 600

1600/75 Hz

1600 x 1200

640/85 Hz 640 x 480

VGA3/60Hz

640 x 480

VGA2/70Hz

720 x 400

Table 3-2. Timing Chart (CSH9839L)

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

Freq. (MHz)

Polarity H.Sync

V.Sync Remark

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

3.810

5.222

17.778

85.008

13.333

0.080

0.427

12.800

0.027

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

93.750

10.667

0.948

1.501

7.901

0.316

75.000

13.333

0.032

0.491

12.800

0.011

202.500

Positive Positive

Separate

Mode

IBM VESA MAC.

Timing

68.677

14.561

1.016

2.201

10.836

0.508

84.997

11.765

0.044

0.524

11.183

0.015

94.500

Positive Positive

Separate

81.400

12.285

0.988

1.624

9.037

0.635

100.000

10.000

0.037

0.516

9.435

0.012

113.309

Negative

Positive

Separate

68.681

14.560

1.280

1.440

11.520

0.320

75.062

13.322

0.044

0.568

12.667

0.044

100.000

Negative Negative

SOG

91.146

10.971

1.016

1.422

8.127

0.406

85.024

11.761

0.033

0.483

11.235

0.011

157.500

Positive Positive

Separate

79.976

12.504

1.067

1.837

9.481

0.119

75.025

13.329

0.038

0.475

12.804

0.013

135.000

Positive Positive

Separate

1024/85 Hz 1024 x 768

1024/100 Hz

1024 x 768

1152/75 Hz 1152 x 870

1280/75 Hz

1280 x 1024

1280/85 Hz

1280 x 1024

Horizontal

Green

Vertical

CSH7839L/CSH9839L 4-1

4 Opearating Instructions

4-1 Front View and Control

436785

Figure 4-1. Front View and Controls

Parallel Button/Trapezoid Button

Adjustment Button

Menu Button

Brightness Control

Contrast Control

1 Power Button

Power Indicator LED (Dual Color)

Size Button/Position Button3

Location Symbol Description

Table 4-1. Front Panel Controls

This monitor has a built-in power management system called PowerSaver. This system saves energy by switching your monitor into a lowpower mode when it has not been used for a certain amount of time. The available modes are “On,” “Standby,” “Suspend,” and “Off.”

This system operates with a VESA DPMS compliant video card installed in your computer. You use a software utility installed on your computer to set up this feature. See the table below for details.

Note 1:This monitor automatically returns to

normal operation when horizontal and vertical sync return. This occurs when you move the computer's mouse or press a key on the keyboard.

Note 2:This monitor is EPA Energy Star

compliant and NUTEK compliant when used with a computer equipped with VESA DPMS functionality. If your computer system cannot support a display power management function, you can purchase an optional DPMS software program to enable the power saving function. Please contact Samsung or your dealer for more information.

Note 3:For energy conservation, turn your

monitor OFF when it is not needed, or when leaving it unattended for long periods.

4 Operating Instructions

4-2 CSH7839L/CSH9839L

State

Items

Normal

Operation

Horizontal Sync Vertical Sync Video

Power Indicator

Power Consumption

Active Active Active

Green Amber

Amber/Green

Blinking

Amber

Blinking

130 W (max.)

110 W (nominal)

Less than

15 W

70 W (nominal)

Less than

5 W

Inactive

Active

Blanked

Active Inactive Blanked

Power Saving Function EPA/NUTEK

Standby Mode

Suspend Mode/

Position A1

Power-off Mode/

Position A2

4-2 Power Management System

Inactive Inactive Blanked

Table 4-2. Display Power Management Signaling (DPMS)

5-1-1 Before making Disassembly

1. Disconnector signal cable and 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. Make sure nothing will damage the screen.

5-1-2 Cabinet Disassembly

1. To uncover the 2 uppermost screws. Press in the end of each screw cap and pull it away from the cabinet.

2. Remove the 4 screw on the Rear Cover and pull it toward to remove it.

5-1-3 Removing the Stand

1. Pull the tab outward on the Chassis Bottom and pull the Tilt and Swivel Base up to remove it.

5-1-4 Removing the Top Shield

1. Remove the 4 screws on the Top Shield Cover and remove the Shield.

CSH7839L/CSH9839L 5-1

5 Disassembly and Reassembly

This section of the service manual describes the disassembly and reassembly procedures for the CSH7839L/CSH9839L monitors.

WARNING: This monitor contains electrostatically sensitive devices. Use caution when handling

these components.

5-1 Disassembly

Cautions:1. Disconnect the monitor from the power source before disassembly.

2. Follow these directions carefully; never use metal instruments to pry apart the cabinet.

Figure 5-1

Figure 5-2

Figure 5-3

5-1-5 Removing the Bottom Shield

1. Remove the 1 screw on the Bottom Shield Cover.

2. Lift off the Bottom Shield.

5-1-6 Removing the CRT Socket PCB

1. Disconnect connectors GT186 and GT188 on the CRT PCB Assembly.

2. Disconnect the CRT Socket PCB Assembly.

5-1-7 Removing the Video PCB Assembly

1. Remove the 4 screws (both side and Rear part of Main PCB Bracket) on the Video PCB.

2. Disconnect CN402, CN104, CN102, CN301 and CN105 on the Video PCB Assembly.

3. Lift off the Video PCB Assembly.

5-1-8 Removing the Video PCB Assembly

Rear Shield and Video PCB

1. Remove the 9 screws on the PCB Assembly.

2. Using pinch-nosed pliers or long-nosed pliers, pull both side taps of Video PCB Assembly.

3. Lift off the Video PCB Assembly Rear Shield.

4. Remove the 3 screws on the Video PCB Bracket.

5. Lift out the Video PCB and pleat it on a flat, level surface that is protected from static electricity.

5-1-9 Removing the Main PCB Assembly

1. Remove both side screws (4 screws) on the lower edge of the CRT Bracket.

2. Remove Chassis Ground Wire on the side of the left.

3. Disconnect CN203, CN601, H_DY and Anode Cap on the Main PCB Assembly.

5 Disassembly and Reassembly

5-2 CSH7839L/CSH9839L

Figure 5-5

Figure 5-6

Figure 5-4

Figure 5-7

5-1-10 Removing the Main PCB

1. Remove 7 screws on the main PCB.

2. Pull the Main PCB towards you and carefully lift out the main PCB and placet it on a flat, level surface that is protected from static electricity.

5-1-11 Removing the Bracket

1. Remove the 10 screws on the Front Cabinet.

5-1-12 Removing the Degaussing Coil

1. Using pinch-nosed pliers or long-nosed pliers, carefully push the 4 plastic ties on the Bracket.

2. Lift the Degaussing Coil Assembly from the Bracket.

5 Disassembly and Reassembly

CSH7839L/CSH9839L 5-3

Figure 5-9

Figure 5-10

Figure 5-8

Figure 5-11

5 Disassembly and Reassembly

5-4 CSH7839L/CSH9839L

5-2 Reassembly

Reassembly procedures are in the reverse order of Disassembly procedures.

6-1-1 Before Making Adjustments

6-1-1 (a) ORIENTATION

When servicing, always face the monitor to the east.

6-1-1 (b) MAGNETIC FIELDS

Whenever possible, use magnetic field isolation equipment such as a Helmholtz field to surround the monitor. If a Helmholtz field is not available, frequently degauss the unit under test.

Caution: Other electrical equipment may cause

external magnetic fields which may interfere with monitor performance.

Use an external degaussing coil to limit magnetic build up on the monitor. If an external degaussing coil is not available, use the internal degaussing circuit. However, do not use the internal degaussing circuit more than once per 30 minutes.

6-1-1 (c) 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.

6-1-1 (d) SIGNAL

Analog, 0.714 Vp-p positive at 75 ohm, internal termination Sync: Separate/Composite (TTL level negative/positive)

Sync-on-Green: Composite sync 0.286 Vp-p negative (Video 0.714 Vp-p positive)

6-1-1 (e) SCANNING FREQUENCY

Horizontal: 30 kHz to 96 kHz (Automatic) Vertical: 50 Hz to 160 Hz (Automatic)

Unless otherwise specified, adjust at the 1024 x 768 mode (H: 68 kHz, V: 85 Hz) signals.

Refer to Table 3-1 on page 3-3.

6-1-1 (f) +B 220 V LINE ADJUSTMENT

Signal: 1024 x 768 mode (68 kHz/85 Hz) Display image: Full white Contrast: Maximum Brightness: Maximum

6-1-1 (g) HIGH VOLTAGE ADJUSTMENT

Signal: 1024 x 768 mode (68 kHz/85 Hz) Display image: Full white Contrast: Maximum Brightness: Maximum Limit: 27 kV ±0.5 kV (19”)

26 kV ± 0.5 kV (17”)

Measure the hight voltage level at the anode cap. High voltage should be within the limit as above. If the high voltage needs adjustment use the following procedure.

PROCEDURE

1. Turn the power off and disconnect the AC line cord from the power source.

2. Unsolder and remove VR501 on the Main PCB.

3. Replace VR501 and adjust the high voltage to the specification.

4. Using a soldering iron, melt the adjustment cap on VR501 to prevent any movement.

6-1-1 (h) G2 (SCREEN) VOLTAGE ADJUSTMENT

Signal: 1024 x 768 mode (68 kHz/85 Hz) Display image: Full white Contrast: Maximum Brightness: Maximum

Adjust the Screen VR of the FBT so that the G2 (Screen) Voltage for SDD is 600 V ± 10 V, for Hitachi it is 600 V ± 10 V and for Toshiba it is 700 V ± 10 V.

6-1-1 (i) CENTER RASTER

Adjust VR401 so that the back raster comes to the center when you apply a signal of 93 kHz/85 Hz.

CSH7839L/CSH9839L 6-1

6 Alignment and Adjustments

This section of the service manual explains how to make permanent adjustments to the monitor. Direction is given for adjustment using the monitor Interface Board Ver. 2.0 and software (SoftJig).

6-1 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.

6-1-1 (j) BRIGHTNESS AND CONTRAST

Unless otherwise specified, adjust control volumes:

Brightness: Maximum Contrast: Maximum

6-1-2 Required Equipment

The following equipment may be necessary for adjustment procedures:

6-1-2 (a) DISPLAY CONTROL ADJUSTMENT

1. Non-metallic (–) screwdriver: 1.5 mm Non-metallic (–) screwdriver: 3 mm

2. Philips (+) screwdriver: 1.5 mm

3. Non-metallic hexkey: 2.5 mm

4. Digital Multimeter (DMM), or Digital Voltmeter (DVM)

5. Signal generator, or Computer with a video board that uses the ET-4000 chipset (strongly recommended if using Samsung DM 200 software) and that displays: 1280 x 1024 @ 85 Hz, or 1600 x 1200 @ 85 Hz (maximum).

6. Personal computer

7. Required software: Softjig.exe from Samsung which includes the cg17p.c data file Samsung DM200, or DisplayMate for Windows from Sonera Technologies

8. Interface Board Ver. 2.0 Code No. BH81-90001K

9. Parallel communications cable (25-pin to 25-pin); Code No. BH81-90001H

10. Signal cable (15-pin to 15-pin cable with additional 3-pin connector); Code No. BH81-90001J

11. 5 V DC adapter, not supplied

Note: SoftJig Ass’y (includes items 8, 9 and 10)

Code No. BH81-90001L

6-1-2 (b) COLOR ADJUSTMENTS

1. All equipment listed in 6-1-2 (a), above

2. Color analyzer, or any luminance measurement equipment

6-1-3 Connecting the SoftJig

Connect the monitor to the signal generator and/ or PC as illustrated in Figures 6-1 and 6-2.

Note: The signal cable connector which includes

the 3-wire cable must connect to the monitor. If you use Setup 2 (PC only, no signal generator) you can only make adjustments to the signal timing available on that computer system. To make corrections to all factory timings requires the use of an additional signal generator.

6-1-4 After Making Adjustments

After finishing all adjustments, test the monitor in all directions. If, for example, the monitor does not meet adjustment specifications when facing north, reposition the monitor to face east and readjust. This time, try for an adjustment closer to the ideal setting within the tolerance range. Test the unit again in all directions. If the monitor again fails to meet specifications in every direction, contact your Regional After Service Center for possible CRT replacement.

6 Alignment and Adjustments

6-2 CSH7839L/CSH9839L

MONITOR

INTERFACE BOARD VER. 2.0

SIGNAL GENERATOR

3-WIRE CABLE

SIGNAL CABLE

5V DC ADAPTOR

PARALLEL CABLE

Figure 6-1. Setup 1, With Signal Generator

MONITOR

INTERFACE BOARD VER. 2.0

3-WIRE CABLE

SIGNAL CABLE

PARALLEL CABLE

D-SUB CONNECTOR

5V DC ADAPTOR

Figure 6-2. Setup 2, Without Signal Generator

6-2-1 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: 352 mm (H) x 264 mm (V) - 19”, 306 mm (H) x 230 mm (V) - 17”. 1024 x 768 mode (68 kHz/85Hz)

Adjust the horizontal position and vertical position to ≤ 4.0 mm of the center point of the screen.

|A-B| ≤ 4.0 mm. |C-D| ≤ 4.0 mm.

Figure 6-3. Centering

6-2-1 (a) HORIZONTAL SIZE ADJUSTMENT CONDITIONS

Scanning frequency: 68 kHz/85 Hz Display image: Crosshatch pattern Brightness: Cut-off Contrast: Maximum

Click on the << or >> box next to H_SIZE to adjust the horizontal size of the display pattern to 352 mm (19”), 306 mm (17”). (Tolerance: ± 3 mm.)

6-2-1 (b) VERTICAL SIZE ADJUSTMENT CONDITIONS

Scanning frequency: 68 kHz/85 Hz Display image: Crosshatch pattern Brightness: Cut-off Contrast: Maximum

Click on the << or >> box next to V_SIZE to adjust the vertical size of the display pattern to 264 mm (19”), 230 mm (17”). (Tolerance: ± 3 mm.)

6-2-1 (c) HORIZONTAL POSITION ADJUSTMENT CONDITIONS

Scanning frequency: 68 kHz/85 Hz Display image: Crosshatch pattern Brightness: Cut-off Contrast: Maximum

Click on the << or >> box next to H_POSI to center the horizontal image on the raster.

6-2-1 (d) VERTICAL POSITION ADJUSTMENT CONDITIONS

Scanning frequency: 68 kHz/85 Hz Display image: Crosshatch pattern Brightness: Cut-off Contrast: Maximum

Click on the << or >> box next to V_POSI to center the vertical image on the raster.

6-2-2 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 Tables 6-1 and 6-2, an image appears distorted, elongated or squashed.

Table 6-1. Factory Preset Modes Linearity

Table 6-2. Other Modes Linearity: VGA, SVGA, XGA,

MAC, etc.

6-2-2 (a) HORIZONTAL LINEARITY ADJUSTMENT CONDITIONS

Scanning frequency: 68 kHz/85 Hz Display image: Crosshatch pattern Brightness: Cut-off Contrast: Maximum

6 Alignment and Adjustments

CSH7839L/CSH9839L 6-3

6-2 Display Control Adjustments

DISPLAY AREA

EDGE OF BEZEL

4 : 3 (19”)

4 : 3 (17”)

5 : 4 (19”)

5 : 4 (17”)

Horizontal: 20.5~23.5 Vertical : 20.5~23.5

Horizontal: 17.8~20.5 Vertical : 17.8~20.5

Horizontal: 19.18~22.07 Vertical : 20.5~23.5

Horizontal: 16.7~19.2 Vertical : 17.8~20.5

Supported Timing Mode

Each block (14 %)

Difference between

adjacent blocks (5 %)

Horizontal: Less than 1.10 mm Vertical : Less than 1.10 mm

Horizontal: Less than 0.96 mm Vertical : Less than 0.96 mm

Horizontal: Less than 1.03 mm Vertical : Less than 1.10 mm

Horizontal: Less than 0.90 mm Vertical : Less than 0.96 mm

4 : 3 (19”)

4 : 3 (17”)

5 : 4 (19”)

5 : 4 (17”)

Horizontal: 20.9~23.1 Vertical : 20.9~23.1

Horizontal: 18.2~20.1 Vertical : 18.2~20.1

Horizontal: 19.60~21.65 Vertical : 20.9~23.1

Horizontal: 17.1~18.9 Vertical : 18.2~20.1

Standard Modes Linearity

Each block (10 %)

Difference between

adjacent blocks (4 %)

Horizontal: Less than 0.88 mm Vertical : Less than 0.88 mm

Horizontal: Less than 0.77 mm Vertical : Less than 0.77 mm

Horizontal: Less than 0.82 mm Vertical : Less than 0.88 mm

Horizontal: Less than 0.72 mm Vertical : Less than 0.77 mm

To adjust the Horizontal Linearity, refer to Tables 6-1 and 6-2 for the tolerance range.

Click on the << or >> box next to H_LIN to optimize the image.

6-2-2 (b) VERTICAL LINEARITY ADJUSTMENT CONDITIONS

Scanning frequency: 68 kHz/85 Hz Display image: Crosshatch pattern Brightness: Cut-off Contrast: Maximum

To adjust the Vertical Linearity, refer to Tables 6-1 and 6-2 for the tolerance range.

Click on the << or >> box next to V_LIN to optimize the image.

6-2-3 Trapezoid Adjustment

CONDITIONS

Scanning frequency: 68 kHz/85 Hz Display image: Crosshatch pattern Brightness: Cut-off Contrast: Maximum

Click on the << or >> box next to TRAPE to make the image area rectangular.

Figure 6-4. Trapezoid

6-2-4 Pinbalance Adjustment

CONDITIONS

Scanning frequency: 68 kHz/85 Hz Display image: Crosshatch pattern Brightness: Cut-off Contrast: Maximum

Click on the << or >> box next to PIN_BAL to optimize the image.

6-2-5 Parallelogram Adjustment

CONDITIONS

Scanning Frequency: 68 kHz/85 Hz Display image: Crosshatch pattern Brightness: Cut-off Contrast: Maximum

Click on the << or >> box next to PARALL to make the image are rectangular.

Figure 6-6. Parallelogram

6-2-6 Side Pincushion Adjustment

CONDITIONS

Scanning frequency: 68 kHz/85 Hz Display image: Crosshatch pattern Brightness: Cut-off Contrast: Maximum

Click on the << or >> box next to BARREL to straighten the sides of the image area.

6-2-7 Tilt Adjustment

CONDITIONS

Scanning Frequency: 68 kHz/85 Hz Display image: Crosshatch pattern Brightness: Cut-off Contrast: Maximum

Click on the << or >> box next to ROTATE to correct the tilt of the display.

6-2-8 Degauss

No adjustments are available for the degaussing circuit. The degaussing circuit can effectively function only once per 30 minutes.

6-2-9 To Delete the User Mode Data

To delete the adjustment data from the user modes, click USER DELETE.

6-2-10 Save the Data

To save the adjustment data for a mode, press FACTORY SAVE.

6 Alignment and Adjustments

6-4 CSH7839L/CSH9839L

| C1 |, | C2 | ≤ 2.0 mm, | D1 |, | D2 | ≤ 2.0 mm.

Figure 6-7. Pincushion

5 mm

| D1 |, | D2 | ≤ 2.0 mm

Figure 6-5. Pinbalance

D1 D2 D1

D2D1

| A - B | < 5 mm

6-3-1 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: 68 kHz/85 Hz Display Size : 352 (H) x 264 (V) - 19”

306 (H) x 230 (V) - 17”

Display image: White flat field at

center of display area Brightness: Cut-off Contrast: Maximum

PROCEDURE

Use the directions in sections 6-3-2 through 6-3-4 to adjust the color coordinates for: 9300K to x = 0.283 ± 0.02, y = 0.298 ± 0.02 6500K to x = 0.313 ± 0.02, y = 0.329 ± 0.02 5000K to x = 0.346 ± 0.02, y = 0.359 ± 0.02

6-3-2 Color Adjustments for 9300K

6-4-2 (a) BACK RASTER COLOR ADJUSTMENT CONDITIONS

Scanning frequency: 68 kHz/85 Hz Display image: Back raster pattern Brightness: Cut-off Contrast: Maximum

1. Select COLOR CHANNEL 1 to control the

color for 9300K.

2. Adjust the luminance of the back raster to

between 0.3 to 1ft-L using the G_CUT controls.

3. Click on the << or >> box next to B_CUT to

set the “y” coordinate to 0.298 ± 0.02.

4. Click on the << or >> box next to R_CUT to

set the “x” coordinate to 0.283 ± 0.02. Note: If the above adjustments cannot be

done to each coordinate, click on the << or >> box next to G_CUT to decrease or increase the green cutoff (bias) and repeat procedures 2 and 3.

6-3-2 (b) G-GAIN ADJUSTMENT

Figure 6-8. Green Box Pattern

CONDITIONS

Scanning frequency: 68 kHz/85 Hz Display image: Green box pattern Brightness: Cut-off Contrast: Maximum

1. Click on the << or >> box next to G_GAIN to

adjust the brightness of the Green Gain to 25 ± 1 ft-L (19”), 30 ± 1 ft-L (17”).

Note: If you can’t increase the Green Gain to

the appropriate value, click on the >> box next to increase the ABL point.

6-3-2 (c) WHITE BALANCE ADJUSTMENT CONDITIONS

Scanning frequency: 68 kHz/85 Hz Display image: Full white pattern Brightness: Cut-off Contrast: Maximum

Figure 6-9. Full White Pattern

1. Click on the << or >> boxes next to R_GAIN and B_GAIN to make the video white. (For 9300K color adjustment: x = 0.283 ± 0.02, y = 0.298 ± 0.02.)

Note: Do not touch the G_GAIN controls.

2. Check the ABL. If it is not within the specifications (30 ± 1 ft-L), use the ABL controls to adjust it.

3. Select COLOR FACTORY SAVE to save the data.

6 Alignment and Adjustments

CSH7839L/CSH9839L 6-5

6-3 Color Adjustments

1/3H-1/2H

1/3V-1/2V

FRONT BEZEL OPENING BACK RASTER

GREEN WINDOW

FRONT BEZEL OPENING BACK RASTER

WHITE WINDOW

6-4-2 (d) WHITE BALANCE ADJUSTMENT VERIFICATION CONDITIONS

Scanning frequency: 68 kHz/85 Hz Display image: Back raster pattern X-Y Coordinates: x = 0.283 ± 0.02,

y = 0.298 ± 0.02 Raster Luminance 0.3 ~ 1ft-L ABL Luminance 30 ± 1 ft-L Brightness: Cut-off Contrast: Maximum

1. Check whether the color coordinates of the

back raster satisfy the above spec. If they do not, return to 6-3-2 (a) and readjust

all settings.

2. Display a full white pattern. Note: Do not touch the G_GAIN controls.

3. Adjust the Contrast Control on the monitor so

that the luminance of the video is about 5 ft-L.

4. Check whether the white coordinates of the

video meet the above coordinates spec.

5. Adjust the Contrast Control again so that the

luminance of the video is about 20 ft-L.

6. Check whether the white coordinates of the

video satisfies the above spec. If they do not, return to 6-3-2 (a) and readjust

all settings.

6-4-3 Color Adjustments for 6500K

6-4-3 (a) BACK RASTER COLOR ADJUSTMENT CONDITIONS

Scanning frequency: 68 kHz/85 Hz Display image: Back raster pattern Brightness: Cut-off Contrast: Maximum

1. Select COLOR CHANNEL 2 to control the

color for 6500K.

2. Adjust the luminance of the back raster to

between 0.3 to 1.0 ft-L using the G_CUT controls.

3. Click on the << or >> boxes next to R_CUT

and B_CUT to adjust the R-Bias to x = 0.313 ±

0.02 and the B-Bias to y = 0.329 ± 0.02.

6-4-3 (b) G-GAIN ADJUSTMENT

This procedure is the same as that for 9300K, refer to the procedure on page 6-5.

6-4-3 (c) WHITE BALANCE ADJUSTMENT CONDITIONS

Scanning frequency: 68 kHz/85 Hz Display image: Full white pattern Brightness: Cut-off Contrast: Maximum

1. Click on the << or >> boxes next to R_GAIN and B_GAIN to make the video white. (For 6500K color adjustment: x = 0.313 ± 0.02, y = 0.329 ± 0.02.)

2. Refer to the procedure for 9300K, section 6-3-2 (c) steps 2 and 3.

6-3-3 (d) WHITE BALANCE ADJUSTMENT VERIFICATION

Refer to the procedure for 9300K, section 6-3-2 (d).

6-3-4 Color Adjustments for 5000K

6-4-4 (a) BACK RASTER COLOR ADJUSTMENT CONDITIONS

Scanning frequency: 68 kHz/85 Hz Display image: Back raster pattern Brightness: Cut-off Contrast: Maximum

1. Select COLOR CHANNEL 3 to control the color for 5000K.

2. Adjust the luminance of the back raster to between 0.3 to 1.0 ft-L using the G_CUT controls.

3. Click on the << or >> boxes next to R_CUT and B_CUT to adjust the R-Bias to x = 0.346 ±

0.02 and the B-Bias to y = 0.359 ± 0.02.

6-3-4 (b) G-GAIN ADJUSTMENT

This procedure is the same as that for 9300K, refer to the procedure on page 6-5.

Adjust the brightness of the G_GAIN less 5 ft-L than brightness of procedure for 9300K.

6-3-4 (c) WHITE BALANCE ADJUSTMENT CONDITIONS

Scanning frequency: 68 kHz/85 Hz Display image: Full white pattern Brightness: Cut-off Contrast: Maximum

1. Click on the << or >> boxes next to R_GAIN and B_GAIN to make the video white. (For 5000K color adjustment: x = 0.346 ± 0.02, y = 0.359 ± 0.02.)

2. Refer to the procedure for 9300K, section 6-3-2 (c) steps 2 and 3.

6 Alignment and Adjustments

6-6 CSH7839L/CSH9839L

6-3-4 (d) WHITE BALANCE ADJUSTMENT VERIFICATION

Refer to the procedure for 9300K, section 6-4-2 (d).

6-3-5 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: 68 kHz/85 Hz

(1024 x 768) Display image: White flat field Display size 352 (H) x 264 (V) - 19”

306 (H) x 230 (V) - 17” Brightness: Cut off point Contrast: Maximum

PROCEDURE

Measure luminance at nine points on the display screen (see figure below).

6-3-6 Focus Adjustment

CONDITIONS

Scanning frequency: 68 kHz/85 Hz 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.

6-3-7 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: 68 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. Very carefully break the glue seal between the 2-pole purity convergence magnets (PCM), the band and the spacer (see Figure 6-11 and 6-12).

3. Make sure the spacing between the PCM assembly and the CRT stem is 29 mm ± 1 mm.

4. Display a green pattern over the entire display area.

5. 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)

6. Repeat steps 4 and 5 using a red pattern and then again, using a blue pattern.

Table 6-3. Color Purity Tolerances

(For 9300K color adjustment: x = 0.283 ± 0.02, y = 0.298 ± 0.02)

7. When you have the PCMs properly adjusted, carefully glue them together to prevent their movement during shipping.

6 Alignment and Adjustments

CSH7839L/CSH9839L 6-7

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

Figure 6-10 Luminance Uniformity Check Locations

Table 6-4. Misconvergence Tolerances

Figure 6-11. Magnet Configuration

Figure 6-12. Toshiba Magnet Configuration

Figure 6-13. Convergence Measurement Areas

6-4-1 Static (Center) Convergence

Static convergence involves alignment of the red, blue and green lines in the center area of the display. See “Dynamic Convergence” for alignment of the color fields around the edges of the display.

CONDITIONS

Direction: Monitor facing east Warm-up: 30 minutes Display image: Crosshatch pattern Tolerances: See Table 6-5

PROCEDURE

As shown in Figure 6-11 and 6-12, the CRT used in these monitors has the same magnet configuration as shown in Table 6-6 below.

Table 6-5. Magnet Order

Use the following steps to correct any static misconvergence:

1. Make sure the display is not affected by external magnetic fields.

2. Locate the pair of 4-pole magnet rings.

3. Unlock the rings and rotate the individual rings (change the spacing between tabs) to converge the vertical red and blue lines.

4. Rotate the pair of rings (maintaining the spacing between tabs) to converge the horizontal red and blue lines.

6 Alignment and Adjustments

6-8 CSH7839L/CSH9839L

6-4 Convergence Adjustments

Misconvergence occurs when one or more of the electron beams in a multibeam CRT fail to meet the other beams at a specified point.

CRT

FRONT

2 3 4

6 7

Samsung SDD and Hitachi CRT

1 Setup Bolt 2 Bow Magnet 3 Band 4 2-Pole Magnet 5 Spacer 6 4-Pole Magnet 7 Spacer 8 6-Pole Magnet 9 Holder 10 Band 11 Tabs

CRT

FRONT

2 3 4

6 7

Toshiba CRT

1 Setup Bolt 2 Bow Magnet 3 Spacer 4 2-Pole Magnet 5 Band 6 6-Pole Magnet 7 Spacer 8 4-Pole Magnet 9 Holder 10 Band 11 Tabs

230 MM

306 MM

CRT Manufacturer Magnet Order from Front of CRT SDD and Hitachi Convergence bow, 2-pole,

4-pole, 6-pole

Toshiba Convergence bow, 2-pole,

6-pole, 4-pole

Position Error in mm CRT Dot Pitch REMARK Center (A) 0.30 0.26 —

Edge (B) 0.50 0.26 < 1024 X 768

0.4 ≥ 1024 X 768

5. After completing the red and blue center convergence adjustment, locate the pair of 6-pole magnet rings.

6. Rotate the individual rings (change the spacing between tabs) to converge the vertical red and blue (magenta) and green lines.

7. Rotate the pair of rings (maintaining the spacing between tabs) to converge the horizontal red and blue (magenta) and green lines. Don’t rotate the 2-pole magnets as they adjust for color purity.

8. Mark the correct position for the magnets and apply a small line of glue to hold the magnets in place. Lock the rings in place.

6-4-2 Dynamic (Edge) Convergence

Use the following procedure to correct minor dynamic (edge) misconvergence. If, after using this procedure, dynamic misconvergence around the periphery of the display area is still greater than the tolerance, contact the Regional After Service Center for possible CRT replacement.

1. Make sure the display is not affected by external magnetic fields.

2. Make sure the static convergence is properly adjusted.

3. Strategically place small rubber magnets on the back of the CRT to correct the misconvergence. Be careful not to remove the paper protecting the adhesive on the magnets until you are satisfied with their placement and the dynamic convergence.

4. When you are satisfied with the convergence around the edge of the CRT, permanently glue the magnets to the back of the CRT.

WARNING: Do not remove or change the

position of the factory installed wedges. These wedges were installed by the CRT manufacturer and are properly placed for this CRT; their removal may result in damage to the CRT.

6 Alignment and Adjustments

CSH7839L/CSH9839L 6-9

Red and Blue Alignment

(4-pole magnet movement)

Red, Blue and Green Alignment

(6-pole magnet movement)

O-Magnetic

Field

Motion (1)

Motion (2)

(1) SPREAD

TAB MAGNET

VERTICAL MISALIGNMENT

HORIZONTAL MISALIGNMENT

SHIFT DIRECTION OF CROSSHATCH PATTERN

MOVE TOGETHER

Figure 6-14. Magnet Movements

B R

G M

6-4-3 Bow Convergence Adjustments

CONDITIONS

Orientation: Monitor facing east. Display Image: Crosshatch pattern with mixed

RGB colors.

Required tools: Flat-head (–) screwdriver, 1.5 mm

Philips (+) screwdriver, 1.5 mm Hexkey, 2.5 mm

PROCEDURE

Bow convergence adjustments are not available for the CRTs used in the CSH7839L/CSH9839L monitors. While all CRTs have bow convergence magnets, they are sealed in the CRT factory and are not user or service technician adjustable. Do not touch these magnets (see Figures 6-11 and 6-

12). If bow convergence adjustment is out of alignment, replace the CRT.

Bow misconvergence should not exceed the values listed in Table 6-5: Misconvergence Tolerances.

6-4-4 Balance Convergence Adjustments

Balance Convergence involves alignment of red and blue lines when they are misaligned at one end more so than at the other end. The Deflection Yoke holds the balance coils which can correct balance misconvergences.

Figure 6-15. SDD and Hitachi Deflection Yoke

Figure 6-16. Toshiba Deflection Yoke

6-4-4 (a) HORIZONTAL LINE RED AND BLUE

BALANCE CONVERGENCE

Figure 6-17. Horizontal Line Balance Misconvergence

Use a 2.5 mm hexkey at the Horizontal Balance Coil (XV). Turning it right raises the right end of the blue line and lowers the left end. Turning the VR to the left lowers the right end of the blue line and raises the left end.

6-4-4 (b) VERTICAL RED AND BLUE BALANCE

CONVERGENCE

Figure 6-18. Vertical Line Balance Misconvergence

Use a 1.5 mm screwdriver (flat-head [–] for SDD DYs and phillips type [+] for Toshiba DYs) at the YH variable register. Turning the VR left tilts the blue line to the right. Turning it right tilts the blue line to the left.

6-4-4 (c) UPPER AND LOWER HORIZONTAL LINE

CONVERGENCE

Figure 6-19. Upper and Lower Balance Misconvergence

Use a 1.5 mm screwdriver (flat-head [–] for SDD DYs and phillips type [+] for Toshiba DYs) at the Yv variable register. Turning the VR to the left moves the blue line at the top upward and at the bottom, the line moves downward. Turning it right moves the blue line at the top downward and at the bottom, the line moves upward.

6 Alignment and Adjustments

6-10 CSH7839L/CSH9839L

BLUE

RED

REDBLUE

RED BLUE

HORIZONTAL BALANCE COIL

CSH7839L/CSH9839L 7-1

7 Troubleshooting

7-1 Parts Level Troubleshooting

Notes: 1. If a picture does not appear, fully rotate the brightness and contrast controls clockwise and reinspect.

2. Check the following circuits.

• No raster appears: Power circuit, Horizontal output circuit, H/V control circuit, and H/V output circuit.

• High voltage develops but no raster appears: Video output circuits.

• High voltage does not develop: Horizontal output circuits.

7-1-1 No Power Supply

Chirping noise exists?

Check and replace Q659,

IC608 and IC607.

Check and replace FG601, D601.

Done.

Yes

Repeating start?

Check and replace Q651, Q602,

ZD601, D615, R606 and D612.

Yes

IC601 Pin 1 waveform is right?

Check and replace IC601, IC602,

IC604, D610 and D611.

Yes

IC602, IC604, D610 and

D611 are right?

Replace parts and verify voltages.

Yes

Normal operation

Replace Main board.

Yes

Verify voltages.

Yes

WAVEFORMS

544 V (IC601, #1)

CH1 P-P = 544 V CH1 RMS = 332.4 V

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