SAMSUNG CKB5237L Service Manual

COLOR MONITOR

CKB5237L CKB7227L

Manual

SERVICE

COLOR MONITOR CONTENTS

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EXIT

1. Precautions

2. Product Specifications

3. Operating Instructions

4. Disassembly & Reassembly

5. Alignment & Adjustments

6. Troubleshooting

7. Exploded View & Parts List

8. Block Diagram

9. Wiring Diagram

10. PCB Diagrams & Electrical Parts List

11. Schematic Diagrams

Samsung Electronics Co., Ltd. October 1997 Printed in Korea Code No.: BH68-60934A

1-1-1 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.

1-1-2 Servicing the High Voltage System 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 10k ohm resistor in series with an insulated wire (such as a test probe) between the chassis and the anode lead. (Disconnect the AC line cord from the AC outlet.)

2. High Voltage VR Replacement If the high voltage system requires adjustment, use the following procedure (all steps are required):

a. Turn the power off and disconnect the AC

line cord from the power source.

b. Unsolder and remove the high voltage VR

on the Main PCB.

c. Replace the VR and adjust the high voltage

to the specification.

d. Using a soldering iron, melt the adjustment

cap on the high voltage VR to prevent any movement.

3. It is essential that service technicians have an accurate high voltage meter available at all times. Check the calibration of this meter periodically.

4. When troubleshooting a monitor with excessively high voltage, avoid being unnecessarily close to the monitor. Do not operate the monitor for longer than is necessary to locate the cause of excessive voltage.

5. High voltage should always be kept at the rated value, no higher. Be sure all service personnel are aware of the procedures and instructions covering X-rays.

The only potential source of X-ray in current solid state display monitors is the tube. However, the CRT does not emit measurable X-ray radiation if the high voltage is at the high voltage adjustment value.

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.

6. When the high voltage regulator is operating properly, there is no possibility of an X-ray problem. Test the brightness and use a meter to monitor the high voltage each time a color monitor comes in for service. Make sure the high voltage does not exceed its specified value and that it is regulating correctly.

7. The CRT is especially designed to prohibit X-ray emissions. To ensure continued X-ray protection, replace the CRT with only one that is the same or equivalent type as the original. Carefully reinstall the CRT shields and mounting hardware; these also provide X-ray protection.

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

9. Do not lift the CRT by the neck.

CKB5237L/7227L 1-1

1 Precautions

Follow these safety, servicing and ESD precautions to prevent damage and to protect against potential hazards such as electrical shock and X-rays.

1-1 Safety Precautions

1-1-3 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.

Figure1-1. Leakage Current Test Circuit

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.

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.

1 Precautions

1-2 CKB5237L/7227L

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

1-2-1 General Servicing Precautions

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 a test component 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.

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.

1 Precautions

CKB5237L/7227L 1-3

1-2 Servicing Precautions

WARNINGS: A high voltage VR replaced in the wrong direction may cause excessive X-ray

emissions. An electrolytic capacitor installed with the wrong polarity might explode.

Cautions: Before servicing instruments covered by this service bulletin, read and follow the

Safety Precautions section of this manual. When replacing the high voltage adjustment VR, it must be fixed by a soldering iron

after it is properly set.

Note: If unforeseen circumstances create conflict between the following servicing precautions and

any of the safety precautions, always follow the safety precautions.

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 wrist-strap 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.

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

1-4 CKB5237L/7227L

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 field-effect transistors. The following techniques will reduce the incidence of component damage caused by static electricity.

CKB5237L/7227L 2-1

2 Product Specifications

2-1 Specifications

Picture Tube: 17-Inch (43 cm): 15.7-inch (39.80 cm) viewable; 15-Inch (38 cm): 13.8-inch (35 cm) viewable;

Full-square flat-face tube, 90˚ Deflection, 0.28 mm Dot pitch, Semi- tint, Non-glare, Invar shadow mask, Anti-static silica coating

Scanning Frequency Horizontal : 30 kHz to 70 kHz (Automatic)

Vertical : 50 Hz to 120 Hz (Automatic)

Display Colors Unlimited colors

Maximum Resolution Horizontal : 1280 Dots

Vertical : 1024 Lines

Input Video Signal Analog, 0.714 Vp-p positive at 75 Ω, internally terminated

Input Sync Signal Separate Sync : TTL level positive/negative

Maximum Pixel Clock rate 110 MHz

Active Display CKB5237L ; Horizontal : 267 mm ± 3 mm, Vertical : 200 mm ± 3 mm

CKB7227L ; Horizontal : 306 mm ± 3 mm (4:3 ratio), Vertical : 230 mm ± 3 mm

Input Voltage AC 90 to 264 Volts, 60 Hz or 50 Hz ± 3 Hz

Power Consumption 90 Watt (max) : 17”, 85 Watt (max) : 15”

Dimensions Unit (W x D x H) 14.6 x 15.6 x 15.5 Inches (370 x 397 x 394 mm), 16.8 x 17.0 x 17.1 Inches (426 x 433 x 434 mm) Carton (W x D x H) 18.2 x 21.0 x 17.7 Inches (462 x 534 x 450 mm) 21.3 x 21.8 x 21.2 Inches (541 x 554 x 538 mm)

Weight CKB5237L : 30 lbs (13.6 kg) / 35.3 lbs (16.0 kg) (Net/Gross) CKB7227L : 40.8 lbs (18.5 kg) / 46.7 lbs (21.2 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 %

CRT Code No. BH03-10337T : M41KUN36X03(E/L/LP), Silica Coating - 17”

BH03-10337U : M41KUN36X03(A/L/LP), Multi Coating - 17” BH03-10337V : M41KUN36X03(T4/L/LP), Multi Coating (TCO) - 17” BH03-10337W : M41KUK35X02(E/LP), ESF - 15” BH03-10337X : M36KUK35X02(T4/LP), Multi Coating (TCO) - 15”

• Above models comply with SWEDAC (MPR II) recommendations for reduced electromagnetic fields.

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

Item Description

CKB5237L CKB7227L

2 Product Specifications

2-2 CKB5237L/7227L

2-2 Pin Assignments

Figure 2-5. Male Type Figure 2-6. Male Type

Sync Type

Pin No.

15-Pin Signal Cable Connector (Figure 2-5)

Cable Adapter (Figure 2-6)

Macintosh

Separate

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

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

CKB5237L/7227L 2-3

800/75 Hz 800 x 600

640/85 Hz 640 x 480

640/75 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 2-1. Timing Chart

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

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

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

46.875

21.333

1.616

3.232

16.162

0.323

75.000

13.333

0.064

0.448

12.800

0.021

49.500

Positive Positive

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

Mode

IBM VESA

Timing

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

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

2 Product Specifications

2-4 CKB5237L/7227L

Table 2-1. Timing Chart Continued

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

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

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

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

Mode

VESA

800/85Hz 800 x 600

1024/85 Hz

1024 x 768

1024/75 Hz 1024 x 768

Timing

Q R S

Video

Sync

Horizontal

Vertical

C D E

Video

Sync

Separate Sync

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

3-1 Front View and Control

3-1-1 CKB5237L/7227L Front View

CKB5237L/7227L 3-1

3 Opearating Instructions

– +

EXIT

– +

EXIT

3456

789

Figure 3-1. Front Control Panel

Figure 3-2. Rear View

1 Power Button

Power Indicator LED (Dual Color)

Menu Display & Menu Exit

Down Button & Brightness

Up Button & Contrast

Menu Selector Enter Key

3 Pin AC Power Input

USB Jack Input (Optional)

Signal Input

Location Symbol Description

Table 3-1. Front Panel Controls

EXIT

–

3-2-1 On Screen Display

This monitor features an On-Screen Display (OSD) that shows information about the display setting. The OSD appears on the screen when you select a function button. The OSD can show the name, range and current setting of the control function. In addition, the OSD shows the current input signal frequency and the list of user and factory preset timings. The OSD remains active for approximately 5 seconds after the completion of any adjustment.

3-2-2 OSD Window

Push the menu button to open the OSD. The Main Menu shows all of the adjustment icons along the top of the window. The window shows one or more adjustment names in the Adjustment Box and instructions display in the Information Bar.

To access a function, use the menu button to move to its associated icon, and then use the or

button to select the adjustment type. Then,

push the ↵ button to access the function.

All OSD windows change color to indicate that the associated adjustment control is active. When the OSD displays the name of the adjustment, for example, Pincushion/Trap, with a green border, adjustments for pincushion or trapezoidal effects are available. Each OSD window shows directions for use along the bottom of the window. When you are satisfied with the adjustments you have made to the current control, select the Exit button to return to the OSD Menu where you can select another control, or exit from the OSD system and save your changes. The OSD remains active for approximately 10 seconds after completion of any adjustments.

3-2-4 Direct Controls

The on-screen Direct controls have the following two functions:

•Brightness:With the menu off, push the button. The brightness display will appear. Push the button to increase the brightness or the button to decrease the brightness.

•Contrast: With the menu off, push the button. The contrast adjustment display will appear. Push the button to increase the contrast or the button to decrease the contrast.

–

+–+–+

–

3 Operating Instructions

3-2 CKB5237L/7227L

BRIGHTNESS

Note 1:This monitor requires a cable adapter for

use with a Macintosh computer. The MacMaster Cable Adapter supports all monitors and all Macintosh, Centris, Quadra, Duo Dock, and Power Macintosh computers. If you do not already have a cable adapter, check with your computer dealer.

Note 2:When used with a computer equipped

with VESA DPMS functions, this monitor is EPA Energy Star compliant and NUTEK compliant.

Table 3-2. Display Power Management Signaling (DPMS)

;CKB7227L

Table 3-3. Display Power Management Signaling (DPMS)

;CKB5237L

3 Operating Instructions

CKB5237L/7227L 3-3

State

Items

Normal

Operation

Horizontal Sync Vertical Sync Video

Power Indicator

Power Consumption/hr

Active Active Active

Green Amber

Alternating

Amber/Green

Blinking

Amber

Blinking

90 W (max.)

78 W

(nominal)

Less than

15 W

72 W (max.)

65 W

(nominal)

Less than

8 W

Inactive

Active

Blanked

Active Inactive Blanked

Power saving function EPA/NUTEK

Stand-By

Mode

Suspend Mode

Position A

Power Off Mode

Position B

Inactive Inactive Blanked

State

Items

Normal

Operation

Horizontal Sync Vertical Sync Video

Power Indicator

Power Consumption/hr

Active Active Active

Green Amber

Alternating

Amber/Green

Blinking

Amber

Blinking

85 W (max.)

70 W

(nominal)

Less than

15 W

72 W (max.)

65 W

(nominal)

Less than

8 W

Inactive

Active

Blanked

Active Inactive Blanked

Power saving function EPA/NUTEK

Stand-By

Mode

Suspend Mode

Position A

Power Off Mode

Position B

Inactive Inactive Blanked

Memo

3 Operating Instructions

3-4 CKB5237L/7227L

4-1-1 Cabinet Disassembly

1. With a pad beneath it, stand the monitor on its front with the screen facing downward and the base close to you. Make sure nothing will damage the screen.

2. Working from the back of the monitor remove the signal cover cap out, and remove the 4 screws and carefully pull the rear cabinet up and off the monitor.

3. Remove the 8 screws on the Top Shield and remove it.

4. Remove the 4 screws on the Bottom Cover and pull it upward to remove it.

5. Using pinch-nosed pliers or long-nosed pliers, carefully disconnect the Anode Cap from the CRT.

4-1-2 Removing the Video PCB &

CRT Socket PCB

1. Follow steps 1 through 5 in “Cabinet Disassembly,” above.

2. Disconnect connectors CN103.

3. Lift off the CRT Socket PCB Assembly.

4. Hold the CRT Socket PCB Assembly while you lift the cap on the CRT Socket and pull out the two focus wires, G2 wire.

5. Remove both side screws on the lower edge of the Video PCB Ass’y and the screw on the signal connector and pull the assembly towards you to remove it.

6. Remove all screws on the Video PCB Assembly and remove the Video Shield.

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

4-1-3 Removing the Main PCB

1. Follow steps 1 through 5 in “Cabinet Disassembly,” steps 1 through 7 in “Removing the Video PCB and “Removing the CRT Socket PCB,” above.

2. Disconnect the Degaussing Coil at CN600 on the Main PCB.

3. Disconnect all easily accessible ground wires from the CRT GND Assembly and Bottom Chassis.

4. Disconnect the connector between CN_Tilt. on the Main PCB and the Tilt coil.

5. Disconnect the DY connector between the DY and the CN300A_7, CN400, CN401 and CN402 connectors on the Main PCB.

6. Remove the 2 screws on the left and right sides of the PCB Bracket.

7. Carefully lift the Main PCB Ass’y.

8. Remove the 7 screws on the top side of the Main PCB.

9. Lift the Main PCB and place it on a flat, level surface that is protected from static electricity.

CKB5237L/7227L 4-1

4 Disassembly and Reassembly

This section of the service manual describes the disassembly and reassembly procedures for the CKB5237L/7227L monitors.

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

these components.

4-1 Disassembly (CKB7227L)

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.

4-1-4 CRT Ass’y Disassembly

1. Complete all previous steps.

2. Remove the 4 side screws 2 on the top and 2 on either side of the CRT and lift the CRT Unit Bracket.

3. Unhook the Degaussing Coil Assembly and lift it off the CRT.

4-2-1 Replacing the CRT

1. Loop the CRT Ground Assembly around the back of the CRT and under the 3 corner, metal ears. Position the corner with the spring last.

2. With the Front Cover Assembly lying face down on a protective pad, position the CRT so that the corner metal ears fit properly in the Front Cover Assembly.

3. Replace the 4 corner screws.

4. Replace the Degaussing Coil Assembly and secure the Coil with the plastic Degaussing Coil Holders.

5. Replace the CRT Ground Assembly.

6. Replace the Unit Bracket Assembly.

4-2-2 Replacing the Main PCB

1. Stand the monitor on its front with the screen facing downward.

2. Replace the 7 screws on the top side of the Main PCB.

3. Position the Main PCB Ass’y in the Front Cabinet and secure it on both sides with the screws between the Bottom Chassis and CRT Unit Bracket.

4. Replace the DY connector at the CN300A_7, CN400, CN401 and CN402 connectors on the Main PCB.

5. Replace the connector between CN_Tilt. on the Main PCB and the Tilt Coil.

6. Replace all easily accessible ground wires on the CRT GND Assembly and Bottom Chassis.

4. Remove the 4 corner screws and lift the CRT up and away from the Front Cover Assembly and place it on a padded surface.

Do not lift the CRT by the neck.

Caution: If you will be returning this CRT to

the monitor, be sure to place the CRT face down on a protective pad.

7. Replace the Degaussing Coil at CN600 on the Main PCB.

8. Replace the Anode Cap.

4-2-3Replacing Connector CN103 on the

Video PCB

1. Position the Video Shield and replace all screws.

2. Replace both side screws on the lower edge of the Video PCB Ass’y and the screw on the signal connector.

4-2-4 Replacing the CRT Socket PCB

1. Hold the CRT Socket PCB Ass’y while you lift the Cap on the CRT Socket and replace the two Focus wires, G2 wire.

2. Reconnect the CRT Socket on the CRT pins at the plug/Socket junction.

4-2-5 Cabinet Reassembly

1. Reconnect CN103 on the Video PCB.

2. Position the Top Shield and replace the 8 screws.

3. Replace the 4 screws on the Bottom Cover.

4. Position the Rear Cover making sure that the tabs along the front edge are properly snapped in place. Replace the 4 screws.

5. Replace the signal cable cover cap.

6. Set the monitor on its Base and make sure that the CRT faceplate was not scratched or otherwise damaged.

4 Disassembly and Reassembly

4-2 CKB5237L/7227L

4-2 Reassembly (CKB7227L)

With the CRT facing downward on a protective pad, use the steps that follow to reassemble the monitor.

4-3-1 Cabinet Disassembly

1. With a pad beneath it, stand the monitor on its front with the screen facing downward and the base close to you. Make sure nothing will damage the screen.

2. Working from the back of the monitor remove the signal cover cap out, and remove the 4 screws and carefully pull the rear cabinet up and off the monitor.

3. Using pinch-nosed pliers or long-nosed pliers, carefully disconnect the Anode Cap from the CRT.

4-3-2 Removing the Video PCB &

CRT Socket PCB

1. Follow steps 1 through 3 in “Cabinet Disassembly,” above.

2. Remove the 1 screw on the Video Shield Top position.

3. Disconnect connector C103.

4. Lift off the CRT Socket PCB Assembly.

5. Hold the CRT Socket PCB Assembly while you lift the cap on the CRT Socket, unsolde 1 point wire, remove 9 pin wire Assembly, unsolder 4 point on the corner shild of CRT Socket PCB and remove shield of CRT Socket PCB.

6. Remove 5 point screws side the lower edge and back of the Video PCB Assembly, and the screw on the signal conector and pull the Assembly towards you to remove it.

7. Remove all screws on the Video PCB Assembly and remove the Video Shield.

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

4-3-3 Removing the Main PCB

1. Follow steps 1 through 3 in “Cabinet Disassembly,” steps 1 through 8 in “Removing the Video PCB and “Removing the CRT Socket PCB,” above.

2. Disconnect the Degaussing Coil at CN600 on the Main PCB.

3. Disconnect all easily accessible ground wires from the CRT GND Assembly and Bottom Chassis.

4. Disconnect the connector between CN_Tilt. on the Main PCB and the Tilt coil.

5. Disconnect the DY connector between the DY and the CN301_5, CN400, CN401 and CN402 connectors on the Main PCB.

6. Remove the 2 screws on the left and right sides of the PCB Bracket.

7. Carefully lift the Main PCB Ass’y.

8. Remove the 7 screws on the top side of the Main PCB.

9. Lift the Main PCB and place it on a flat, level surface that is protected from static electricity.

4 Disassembly and Reassembly

CKB5237L/7227L 4-3

4-3 Disassembly (CKB5237L)

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.

4-4-1 Replacing the CRT

1. Loop the CRT Ground Assembly around the back of the CRT and under the 4 corner, metal ears. Position the corner with the spring last.

2. With the Front Cover Assembly lying face down on a protective pad, position the CRT so that the corner metal ears fit properly in the Front Cover Assembly.

3. Replace the 4 corner screws.

4. Replace the Degaussing Coil Assembly and wrap the coil with the plastic coated matal ties to hold the coil in place.

5. Replace the CRT Ground Assembly.

6. Replace the Unit Bracket Assembly.

4-4-2 Replacing the Main PCB

1. Stand the monitor on its front with the screen facing downward.

2. Replace the 7 screws on the top side of the Main PCB.

3. Position the Main PCB Ass’y in the Front Cabinet and secure it on both sides with the screws between the Bottom Chassis and CRT Unit Bracket.

4. Replace the DY connector at the CN301_5, CN400, CN401 and CN402 connectors on the Main PCB.

5. Replace the connector between CN_Tilt. on the Main PCB and the Tilt Coil.

6. Replace all easily accessible ground wires on the CRT GND Assembly and Bottom Chassis.

7. Replace the Degaussing Coil at CN600 on the Main PCB.

8. Replace the Anode Cap.

4-4-3Replacing Connector CN103 on the

Video PCB

1. Position the Video Shield and replace all screws.

2. Replace 4 point both and back screws on the lower edge of the Video PCB Ass’y and the screw on the signal connector.

4-4-4 Replacing the CRT Socket PCB

1. Hold the CRT Socket PCB Ass’y while you lift the Cap on the CRT Socket and replace the Focus wire, G2 wire.

2. Reconnect the CRT Socket on the CRT pins at the plug/Socket junction.

4-4-5 Cabinet Reassembly

1. Reconnection CN103 both the CRT and the Video PCB.

2. Solder 1 point CRT PCB and replace 1 screw Video shield.

3. Replace the 4 screws on the Bottom Cover.

4. Position the Rear Cover making sure that the tabs along the front edge are properly snapped in place. Replace the 4 screws.

5. Replace the signal cable cover cap.

6. Set the monitor on its Base and make sure that the CRT faceplate was not scratched or otherwise damaged.

4 Disassembly and Reassembly

4-4 CKB5237L/7227L

4-4 Reassembly (CKB5237L)

With the CRT facing downward on a protective pad, use the steps that follow to reassemble the monitor.

5-1-1 Before Making Adjustments

5-1-1 (a) ORIENTATION

When servicing, always face the monitor to the east.

5-1-1 (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.

5-1-1 (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.

5-1-1 (d) SIGNAL

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

5-1-1 (e) SCANNING FREQUENCY

Horizontal: 30 kHz to 70 kHz (Automatic) Vertical: 50 Hz to 120 Hz (Automatic)

Unless otherwise specified, adjust at the 17”: 1024 x 768 mode (68 kHz/85 Hz), 15”: 800 x 600 mode (54 kHz/85 Hz) signals.

Refer to Table 2-1 on pages 2-4 and 2-5.

5-1-1 (f) HIGH VOLTAGE ADJUSTMENT

Signal: No signal Display image: Self raster Contrast: Maximum Brightness: Maximum Limit: 26 kV ± 0.2 kV (17”)

25 kV ± 0.2 kV (15”)

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.

5-1-1 (g) G2 (SCREEN) VOLTAGE ADJUSTMENT (17” ONLY)

Signal: No signal Display image: Self raster Contrast: Maximum Brightness: Maximum

Adjust the Screen VR of the FBT so that the G2 (Screen) Voltage for SDD CRT is 450 V ± 10 V.

5-1-1 (h) CENTER RASTER

Adjust SW401 so that the back raster comes to the center when you apply a signal of 60 kHz/75 Hz.

CKB5237L/7227L 5-1

5 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. 2.0 and software (SoftJig).

5-1 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.

5-1-2 Required Equipment

The following equipment may be necessary for adjustment procedures:

5-1-2 (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: 1024 x 768 @ 85 Hz, or 800 x 600 @ 85 Hz (minimum).

6. Personal computer

7. Required software: Softjig.exe from Samsung which includes the cg17e.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

5.1-2 (b) COLOR ADJUSTMENTS

1. All equipment listed in 5-1-2 (a), above

2. Color analyzer, or any luminance measurement equipment

5-1-3 Connecting the SoftJig

Connect the monitor to the signal generator and/ or PC as illustrated in Figures 5-1 and 5-2.

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.

5-1-4 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.

5 Alignment and Adjustments

5-2 CKB5237L/7227L

MONITOR

INTERFACE BOARD VER. 2.0

SIGNAL GENERATOR

3-WIRE CABLE

SIGNAL CABLE

5V DC ADAPTOR

PARALLEL CABLE

Figure 5-1 : 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 5-2. Setup 2, Without Signal Generator

5-2-1 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: 306 mm (H) x 230 mm (V) for 17”, 267 mm (H) x 200 mm (V) for 15”.

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 5-3. Centering

5-2-1 (a) HORIZONTAL SIZE ADJUSTMENT CONDITIONS

Scanning frequency: 68 kHz/85 Hz (17”)

54 kHz/85 Hz (15”) Display image: Crosshatch pattern Brightness: Maximum Contrast: Maximum

Click on the << or >> box next to B+OUT to adjust the horizontal size of the display pattern to 306 mm (17”) and 267 mm (15”). (Tolerance: ± 3 mm.)

5-2-1 (b) VERTICAL SIZE ADJUSTMENT CONDITIONS

Scanning frequency: 68 kHz/85 Hz (17”)

54 kHz/85 Hz (15”) Display image: Crosshatch pattern Brightness: Maximum Contrast: Maximum

Click on the << or >> box next to V_SIZE to adjust the vertical size of the display pattern to 230 mm (17”) and 200 mm (15”). (Tolerance: ± 3 mm.)

5-2-1 (c) HORIZONTAL POSITION ADJUSTMENT CONDITIONS

Scanning frequency: 68 kHz/85 Hz (17”)

54 kHz/85 Hz (15”)

Display image: Crosshatch pattern Click on the << or >> box next to H_POSI to

center the horizontal image on the raster.

5-3-1 (d) VERTICAL POSITION ADJUSTMENT CONDITIONS

Scanning frequency: 68 kHz/85 Hz (17”)

54 kHz/85 Hz (15”)

Display image: Crosshatch pattern Click on the << or >> box next to V_POSI to

center the vertical image on the raster.

5-2-2 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 5-2 and 5-3, an image appears distorted, elongated or squashed.

Table 5-1. Standard Modes Linearity: 640x480/75Hz,

800x600/85Hz and 1024x768/85Hz

Table 5-2. Other Modes Linearity: VGA, SVGA, XGA,

MAC, etc.

5 Alignment and Adjustments

CKB5237L/7227L 5-3

5-2 Display Control Adjustments

DISPLAY AREA

EDGE OF BEZEL

4 : 3

5 : 4

Horizontal: 17.8~20.5 Vertical : 17.8~20.5

Horizontal: 16.7~19.2 Vertical : 17.8~20.5

Supported Timing Mode

Each block (14 %)

Difference between

adjacent blocks (5 %)

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

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

4 : 3

5 : 4

Horizontal: 18.2~20.1 Vertical : 18.2~20.1

Horizontal: 17.1~18.9 Vertical : 18.2~20.1

Standard Modes Linearity

Each block (10 %)

Difference between

adjacent blocks (4 %)

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

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

5-2-2 (a) HORIZONTAL LINEARITY ADJUSTMENT

The CKB5237L/7227L monitors offer only Vertical Linearity adjustments. Horizontal Linearity is fixed on the Chassis and is not adjustable.

5-2-2 (b) VERTICAL LINEARITY ADJUSTMENT CONDITIONS

Scanning frequency: 68 kHz/85 Hz (17”)

54 kHz/85 Hz (15”) Display image: Crosshatch pattern Brightness: Maximum Contrast: Maximum

To adjust the Vertical Linearity, refer to Tables 5-2 and 5-3 for the tolerance range.

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

5-2-3 Trapezoid Adjustment

CONDITIONS

Scanning frequency: 68 kHz/85 Hz (17”)

54 kHz/85 Hz (15”) Display image: Crosshatch pattern Brightness: Maximum Contrast: Maximum

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

Figure 5-4. Trapezoid

5-2-4 Pinbalance Adjustment

CONDITIONS

Scanning frequency: 68 kHz/85 Hz (17”)

54 kHz/85 Hz (15”) Display image: Crosshatch pattern Brightness: Maximum Contrast: Maximum

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

5-2-5 Parallelogram Adjustment

CONDITIONS

Scanning Frequency: 68 kHz/85 Hz (17”)

54 kHz/85 Hz (15”) Display image: Crosshatch pattern Brightness: Maximum Contrast: Maximum

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

Figure 5-6. Parallelogram

5 Alignment and Adjustments

5-4 CKB5237L/7227L

| A - B | < 4 mm

4 mm

D1 D2 D1

Figure 5-5. Pinbalance

5-2-6 Side Pincushion Adjustment

CONDITIONS

Scanning frequency: 68 kHz/85 Hz (17”)

54 kHz/85 Hz (15”)

Display image: Crosshatch pattern Click on the << or >> box next to BARREL to

straighten the sides of the image area.

5-2-7 Tilt Adjustment

CONDITIONS

Scanning Frequency: 68 kHz/85 Hz (17”)

54 kHz/85 Hz (15”) Display image: Crosshatch pattern Brightness: Maximum Contrast: Maximum

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

5-2-8 Degauss

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

5-2-9 To Delete the User Mode Data

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

5-2-10 Save the Data

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

5 Alignment and Adjustments

CKB5237L/7227L 5-5

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

Figure 5-7. Pincushion

D1 D2

5-3-1 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 (17”)

54 kHz/85 Hz (15”)

Display image: White flat field at

center of display area

Luminance: Maximum

PROCEDURE

Use the directions in sections 5-4-2 through 5-4-3 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

5-3-2 Color Adjustments for 9300K

5-3-2 (a) BACK RASTER COLOR ADJUSTMENT CONDITIONS

Scanning frequency: 68 kHz/85 Hz (17”)

54 kHz/85 Hz (15”) Display image: Back raster pattern Brightness: Maximum Contrast: Maximum

(for 17”)

1. Select COLOR CHANNEL 1 to control the

color for 9300K.

2. Adjust the luminance of the back raster to

between 0.5 to 0.7 ft-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.

(for 15”)

1. Select COLOR CHANNEL 1 to control the

color for 9300K.

2. Adjust the luminance of the back raster to

between 0.5 to 0.7 ft-L using the Screen VR (T501) 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 3 and 4.

5-3-2 (b) G-GAIN ADJUSTMENT

Figure 5-8. Green Box Pattern

CONDITIONS

Scanning frequency: 68 kHz/85 Hz (17”)

54 kHz/85 Hz (15”) Display image: Green box pattern Brightness: Maximum Contrast: Maximum

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

adjust the brightness of the Green Gain to 40 ± 1 ft-L.

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

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

5-3-2 (c) WHITE BALANCE ADJUSTMENT CONDITIONS

Scanning frequency: 68 kHz/85 Hz (17”)

54 kHz/85 Hz (15”) Display image: Full white pattern Brightness: Maximum Contrast: Maximum

Figure 5-9. Full White Pattern

5 Alignment and Adjustments

5-6 CKB5237L/7227L

1/3H-1/2H

1/3V-1/2V

FRONT BEZEL OPENING BACK RASTER

GREEN WINDOW

FRONT BEZEL OPENING BACK RASTER

WHITE WINDOW

5-3 Color Adjustments

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