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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.

5-1-1

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 procedures. Warm-up time is especially critical in Color Temperature and White Balance adjustments. 5-1-1 (d) SIGNAL Analog, 0.7 Vp-p positive at 75 ohm, internal termination Sync: Separate (TTL level negative/positive) 5-1-1 (e) SCANNING FREQUENCY Horizontal: 30 kHz to 55 kHz (automatic) 14 30 kHz to 61 kHz (automatic) 15 Vertical: 50 Hz to 120 Hz (automatic) Unless otherwise specified, adjust at the 800 x 600 mode (H : 53.7 kHz, V: 85 Hz) -14/15 signals. Refer to Table on page 2-3.

5-1-1 (f) +B 13 V LINE CHECK No beam Contrast: Maximum Brightness: Maximum Check the DC 13 V 0.2 V at Cathode of D616 Point and GND. 5-1-1 (g) HIGH VOLTAGE CHECK No beam Contrast: Maximum Brightness: Maximum Check the high voltage to 24.5 0.5 kV - 14, 25 0.5 kV - 15 at anode and GND. 5-1-1 (h) CENTER RASTER Adjust VR501 so that the back raster comes to the center when you apply a signal of 60 kHz/75 Hz - 15 . 5-1-1 (i) BRIGHTNESS AND CONTRAST Unless otherwise specified, adjust brightness and contrast buttons: Brightness: Maximum (press button until the LED is blink) Contrast: Maximum (press button until the LED is blink)

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)

DP14L*/DP15L*

5-1

5 Alignment and Adjustments 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: 800 x 600 @ 85 Hz, or 800 x 600 @ 75 Hz (minimum). 6. Personal computer 7. Required software: Softjig.exe from Samsung, 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 Assembly (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
INTERFACE BOARD VER. 2.0 5V DC ADAPTOR PARALLEL CABLE PC 7 PIN MINI DIN CONNECTOR SIGNAL CABLE D-SUB CONNECTOR

MONITOR INTERFACE BOARD VER. 2.0 5V DC ADAPTOR PARALLEL CABLE PC SIGNAL GENERATOR SIGNAL CABLE

7 PIN MINI DIN CONNECTOR

Figure 5-1. Setup 1, With Signal Generator

MONITOR

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. Figure 5-2. Setup 2, Without 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.

5-2

DP14L*/DP15L*

5 Alignment and Adjustments

5-2 Display Control Adjustments
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: 267 mm (H) x 200 mm (V) for 15, 255 mm (H) x 191 mm (V) for 14 Adjust the horizontal position and vertical position to within 4.0 mm of the center point of the screen. l A - B l 5.0 mm. l C - D l 5.0 mm.
C DISPLAY AREA A B EDGE OF BEZEL D

5-2-1 (b) VERTICAL SIZE ADJUSTMENT CONDITIONS Scanning frequency: Display image: Brightness: Contrast: 53.7 kHz/85 Hz Crosshatch pattern Maximum Maximum

Adjust the vertical size of the display pattern to 200 mm (15) and 191 mm (14). (Tolerance: 3 mm.) 5-2-1 (c) HORIZONTAL POSITION ADJUSTMENT CONDITIONS Scanning frequency: Display image: 53.7 kHz/85 Hz Crosshatch pattern

PROCEDURE Center the test pattern on the raster. 5-2-1 (d) VERTICAL POSITION ADJUSTMENT CONDITIONS Scanning frequency: Display image: 53.7 kHz/85 Hz Crosshatch pattern

Figure 5-3. Centering 5-2-1 (a) HORIZONTAL MINIMUM SIZE ADJUSTMENT CONDITIONS Scanning frequency: Display image: Brightness: Contrast: 53.7 kHz/85 Hz Crosshatch pattern Maximum Maximum

Center the test pattern 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 5-1 and 5-2, an image appears distorted, elongated or squashed. The formular of linearity (%)
= 2 x (Max Min) Max + Min x 100

PROCEDURE Horizontal minimum size can be adjusted as follows using Softjig. 1. Display the timing 800 x 600/85 Hz. 2. Adjust horizontal size to minimum size using H_SIZE. 3. Adjust horizontal minimum size to 250 mm (15) or 242 mm (14) using H_SIZE MIN. 4. Adjust horizontal size to 267 mm (15) or 255 mm (14) using H_SIZE. 5. Press the ALL MODE SAVE horizontal minimum size for each timing is saved automatically. If horizontal minimum size range cannot meet the spec, horiontal maximum size of 640 x 480/75 Hz including 800 x 600/60 Hz, 56 Hz, may be saturated or cannot overscan the bezel.

Table 5-1. Standard Modes Linearity: 800 x 600/85Hz
Standard Timing Modes Each block (10 %) Difference between adjacent blocks (4 %)

Table 5-2. Other Modes Linearity: VGA, SVGA, XGA, MAC, etc.
Supported Timing Mode Each block (14 %) Difference between adjacent blocks (5 %)

DP14L*/DP15L*

5-3

5 Alignment and Adjustments

5-2-3 Trapezoid Adjustment
CONDITIONS Scanning frequency: Display image: 53.7 kHz/85 Hz Crosshatch pattern

5-2-6 CRT Tilt Adjustment ( Option)
TILT ADJUSTMENT (DP15L* With Tilt) Push the V-Posi and H-Size simultaneously until Led blinks and back on again. Push the Increase (+) and Decrease () buttons to correct the Tilt.
A B C D

Make the the test pattern rectangular.
2.2 mm 2.2 mm

FRONT BEZEL BACK RASTER

Figure 5-7. CRT Tilt Adjustment
2.2 mm 2.2 mm

5-2-7 Vertical Linearity Adjustment
To activate the vertical linearity adjustment, push both the horizontal position and horizontal size buttons and hold then in for longer than 3 seconds, or until the power indicator LED changes from green to blink and back to green. Use the Increase (+) and Decrease () buttons to correct the display shape.

Figure 5-4. Trapezoid

5-2-4 Parallelogram Adjustment
CONDITIONS Scanning frequency: Display image: 53.7 kHz/85 Hz (14/15) Crosshatch pattern

To activate the Parallelogram Adjustment function, push both the Horizontal Position and Vertical Position buttons and hold them in for longer than 3 seconds, or until the power indicator LED changes from green to blink and back to green. Use the Increase (+) and Decrease () buttons to correct the display shape.

5-2-8 Pin Balance Adjustments
To activate the pin balacne function, push both the horizontal position and vertical Size buttons and hold then in for longer than 3 seconds, or until the power indicator LED changes from green to blink and back to green. Use the Increase (+) and Decrease () buttons to correct the display shape.

5-2-9 Degauss
2.2 mm

Figure 5-5. Parallelogram

5-2-5 Side Pincushion Adjustment
CONDITIONS Scanning frequency: Display image: 53.7 kHz/85 Hz (14/15) Crosshatch pattern

Push the contrast and brightness buttons simultaneously. The degaussing circuit can effectively function only once per 30 minutes. If available, use an external degaussing coil during servicing.

5-2-10 Delete User Mode Data
To delete the picture data from the user modes, push the contrast button and side pincushion button for 5 or more seconds simultaneously.

After pushing the Side Pincushion button once, push the Increase (+) and Decrease () buttons to straighten the sides of the test pattern.
| C1 |, | C2 | 2.0 mm, | D1 |, | D2 | 2.2 mm. C2

5-2-11 Recall
To delete the picture data from current user mode, push the contrast button and trapzoid button for 5 or more seconds simultaneoulsy.

D1

D2

C1

Figure 5-6. Pincushion

5-4

DP14L*/DP15L*

5 Alignment and Adjustments

5-3 Color Adjustments
Before making adjustments, check that the video signals are as follows: Video : Analog, 0.7 Vp-p (at 75 termination) Sync : Separate TTL level Unless otherwise specified, use 800 x 600 mode signal (53.7 kHz/85 Hz) for adjustments.

5-3-3 Video Gain Adjustment
1/3H-1/2H FRONT BEZEL OPENING 1/3V-1/2V BACK RASTER GREEN WINDOW

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: 53.7 kHz/85 Hz Display image: White flat field at center of display area Luminance: Maximum PROCEDURE Using the directions in sections 5-3-2 through 5-3-5, adjust the Color Coordinates for 9300K to x = 0.283 0.02 and y = 0.298 0.02 Figure 5-8. Green Box Pattern CONDITIONS Measurement instrument: Color analyzer Scanning frequency: 53.7 kHz/85 Hz Display image: Green box pattern within range for which the ABL circuit is not active (1/3 to 1/2H and 1/3 to 1/2V). Brightness: Maximum Contrast: Maximum PROCEDURE 1. Adjust G-Gain so that the brightness of the green gain is 40 1 ft-L (typically 40 ft-L).

5-3-4 White Balance Adjustment
FRONT BEZEL OPENING

5-3-2 Back Raster Color Adjustment
CONDITIONS Measurement instrument: Scanning frequency: Display image: Brightness: Contrast: Color analyzer 53.7 kHz/85 Hz Back raster pattern Maximum Maximum
BACK RASTER WHITE WINDOW

Figure 5-9. Full White Pattern CONDITIONS Measurement instrument: Scanning frequency: Display image: Brightness: Contrast:

PROCEDURE 1. Adjust the Screen VR on the FBT so that the brightness of the Back Raster is 0.3 to 0.5 ft-L (typically 0.4 ft-L). 2. Adjust the G_CUT to center. 3. Adjust the B_CUT to set the y coordinate to 0.298 0.02. 4. Adjust the R_CUT to set the x coordinate to 0.283 0.02. Note: If the above adjustments cannot be done to each coordinate, adjust G_CUT to increase or decrease the green cutoff and repeat procedures 3 and 4.

Color analyzer 53.7 kHz/85 Hz Full white pattern Maximum Maximum

PROCEDURE 1. Display the full white pattern. 2. Adjust R-Gain and B-Gain so that the video is white. (x = 0.283 0.02 and y = 0.298 0.02)

DP14L*/DP15L*

5-5

5 Alignment and Adjustments

5-3-5 White Balance Fine Adjustment
CONDITIONS Measurement instrument: Scanning frequency: Display image: X-Y coordinates: Color analyzer 53.7 kHz/85 Hz Full white pattern x = 0.283 0.02 y = 0.298 0.02

5-3-9 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: 53.7 kHz/85 Hz Display image: White flat field Luminance: Cutoff point at the center of the display area Caution: 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. Use an external degaussing coil to neutralize magnetic fields which may be affecting color purity. 2. Very carefully break the glue seal between the 2-pole purity convergence magnets (PCM), the band and the spacer . 3. Make sure the spacing between the PCM assembly and the CRT stem is 22.5 mm 1 mm. 4. Display a red pattern over the entire display area. 5. Adjust the Purity Magnet Rings on the PCM assembly to display a pure green pattern. (Optimal setting: x = x = 0.283 0.02, y = 0.298 0.02) 6. Repeat steps 4 and 5 using a red pattern and then again, using a blue pattern. Table 5-3. Color Purity Tolerances Red: Green: Blue: x = 0.625 0.015 x = 0.310 0.015 x = 0.150 0.015 y = 0.340 0.015 y = 0.592 0.015 y = 0.063 0.015

PROCEDURE 1. Adjust the Contrast control so that the brightness of the video is about 5 ft-L. 2. Check whether the white coordinates of the video meet the specification above. If they do not, adjust them so that they do. 3. Adjust the Contrast to maximum luminance. 4. Check whether the white coordinates still meet the specification above. If they do not, adjust them so that they do.

5-3-6 ABL Point Adjustment
CONDITIONS Measurement instrument: Color analyzer Scanning frequency: 53.7 kHz/85 Hz Display image: Full white pattern Brightness: Maximum Contrast: Maximum PROCEDURE Adjust ABL so that the brightness level is 35 1 ft-L.

5-3-7 Focus Adjustment
CONDITIONS Measurement instrument: Color analyzer Scanning frequency: 53.7 kHz/85 Hz Display image: H character pattern Brightness: Maximum 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.

5-3-8 Luminance Uniformity Check
CONDITIONS Measurement instrument: Color analyzer Scanning frequency: 53.7 kHz/85 Hz Display image: White flat field Brightness: Cut off point at 30 ft-L PROCEDURE Measure luminance at nine points on the display screen: top left corner, top center, top right corner, center row left side, center, center row right side, bottom left corner, bottom center, and bottom right corner. 5-6

(For 9300K white color adjustment: x = 0.283 0.02, y = 0.298 0.02) 7. When you have the PCMs properly adjusted, carefully gule them together with Locktite to prevent their movement during shipping.

DP14L*/DP15L*