SAMSUNG DP14LT7NING Service Manual
COLOR MONITOR
DP14LS
DP14LT
DP15LS
DP15LT
Manual
SERVICE
COLOR MONITOR CONTENTS
1. Precautions
2. Product Specifications
3. Operating Instructions
4. Disassembly & Reassembly
5. Alignment & Adjustments
6. Troubleshooting
7. Exploded View & Parts List
8. Electrical Parts List
9. Block Diagram
10. Wiring Diagram
11 Schematic Diagrams
Samsung Electronics Co., Ltd. April 1999
Printed in Korea
Code No.: BH68-00128A
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:Damaged IC202 may cause excessive
x-ray emissions.
1. When servicing the high voltage system, remove
the static charge by connecting a 10 kohm resistor
in series with an insulated wire (such as a test
probe) between the chassis and the anode lead.
2. If the HV VR requires adjustment:
This monitor does not need to adjust high voltage,
high voltage step is saved at IC202, adjusting this
high voltage to 24.5±0.5 kV - 14Ó, 25.0±0.5 kV - 15Ó.
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
unitÕs 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.
DP14L*/DP15L* 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 unitÕs 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 Òanti-staticÓ
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 instrumentÕs ground lead to
the instrument chassis ground before connecting the
positive lead; always remove the instrumentÕs
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 DP14L*/DP15L*
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: An electrolytic capacitor installed with the wrong polarity might explode.
DP14L*/DP15L* 2-1
2 Product Specifications
2-1 Specifications
Picture Tube: 14-Inch (36 cm); 13.2-Inch (33.5 cm) viewable, 90° Deflection,
15-Inch (38 cm); 13.8-Inch (35 cm) viewable, flat-face tube, 90° Deflection,
0.28 mm Dot pitch, Semi-tint, Non-glare, Antistatic silica coating, Invar shadow mask
Scanning Frequency Horizontal: 30 kHz to 55 kHz (Automatic) - 14” / 30 kHz to 61 kHz (Automatic) - 15”
Vertical: 50 Hz to 120 Hz (Automatic)
Display Colors Unlimited colors
Maximum Resolution Horizontal : 1024 Dots
Vertical : 768 Lines
Input Video Signal Analog, 0.7 Vp-p positive at 75 Ω, internally terminated
Input Sync Signal Separate Sync : TTL level positive/negative
Maximum Pixel Clock 14” : 65 MHz, 15” : 80 MHz
Active Display 14” 15”
Horizontal 255 mm ± 4 mm (4:3 ratio) 267 mm ± 4 mm (4:3 ratio)
Vertical 191 mm ± 4 mm 200 mm ± 4 mm
Input Voltage AC 90 to 264 Volts, 60 Hz/50 Hz ± 3 Hz
Power Consumption 75 Watt (Max.)
Dimensions 14” 15”
Unit (W x D x H) 13.70 x 14.65 x 14.49 Inches (348 x 372 x 368 mm) 14.25 x 15.12 x 15.12 Inches (362 x 384 x 384 mm)
Carton (W x D x H) 16.61 x 18.11 x 15.35 Inches (422 x 460 x 390 mm) 17.87 x 19.57 x 17.52 Inches (454 x 497 x 445 mm)
Weight (Net/Gross) 14” : 23.4 lbs (10.6 kg) / 26.9 lbs (12.2 kg)
15” : 26.5 lbs (12.0 kg) / 31.5 lbs (14.3 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 %
• This above Models complies with SWEDAC (MPR II) recommendations for reduced electromagnetic fields.
• Designs and specifications are subject to change without prior notice.
Item Description
2 Product Specifications
2-2 DP14L*/DP15L*
2-2 Pin Assignments
Sync
Type
Pin No.
15-Pin Signal Cable Connector (Figure 2-1)
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
5
15
Figure 2-1. Male Type
2 Product Specifications
DP14L*/DP15L* 2-3
fH (kHz)
A µsec
B µsec
C µsec
D µsec
E µsec
fV (Hz)
O msec
P msec
Q msec
R msec
S msec
Clock
Frequency
(MHz)
Polarity
H.Sync
V.Sync
Remark
IBM VESA
800/85 Hz
800 x 600
1024/60 Hz
1024 x 768
(14”)
1024/75 Hz
1024 x 768
(15”)
640/60 Hz
640 x 480
720/70 Hz
720 x 400
31.469
31.777
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
43.269
23.111
1.556
2.222
17.778
1.556
85.008
11.764
0.069
0.578
11.093
0.023
36.000
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
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
48.363
20.677
2.092
2.462
15.754
0.369
60.004
16.666
0.124
0.600
15.880
0.062
65.000
Negative
Negative
Separate
60.023
16.660
13.003
3.658
13.206
3.454
75.029
13.328
12.795
0.533
12.812
0.516
78.750
Positive
Positive
Separate
800/75 Hz
800 x 600
640/75 Hz
640 x 480
640/85 Hz
640 x 480
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.
QRS
P
O
Video
Sync
Sync
Horizontal
Vertical
CDE
P
O
B
A
Video
Sync
Sync
Separate Sync
Table 2-1. Timing Chart
Mode
Timing
C D
A
O
E
B
P
Video
Sync
Sync
Video
Q R S
A : Line time total B : Horizontal sync width O : Frame time total P : Vertical sync width
C : Back porch D : Active time Q : Back porch R : Active time
E : Front porch S : Front porch
VIDEO
A
B
O
P
Q
R
S
Horizontal
Vertical
H/V Composite Sync
Memo
2 Product Specifications
2-4 DP14L*/DP15L*
DP14L*/DP15L* 3-1
Location Symbol Description
1 Power Button
Power Indicator LED
Adjustment Buttons
Side Pincushion Button
Horizontal Position Button
Trapezoid Button
Brightness Control
Contrast Control
Parallelogram
V-Linearity
Pinbalance Button
Degauss
Recall
User Delete
Tilt (Option: 15”)
V-Moire
Vertical Size Button
Vertical Position Button
Horizontal Size Button
3
4
8
9
10
11
12
13
14
15
16
17
18
19
5
6
7
2
3
12
13
14 17
16
15
45186 7 8 9 10 11
1
2
19
Table 3-1. Front Panel Controls
Figure 3-1. Front Control Panel
+
+
+
+
+
+
+
+
3 Operating Instructions
3-1 Front View and Control
Memo
3 Operating Instructions
3-2 DP14L*/DP15L*
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 closest to you. Make sure nothing will
damage the screen.
2. Remove the Stand from the monitor.
(Refer to Stand manual)
3. Incline the monitor by lifting the rear of the
monitor.
4. Push the Opening jig each groove along the
top of the monitor till it makes a ÒttakÓ sound.
(2 grooves : Left and Right, Make sure each
snap is disengaged.)
5. Squeeze the hold-snap on bottom of the
monitor using your hand.
6. Insert the Opening jig into the groove then
release the hold-snap.
DP14L*/DP15L* 4-1
4 Disassembly and Reassembly
This section of the service manual describes the disassembly and reassembly procedures for the
DP14L*/DP15L* monitors.
WARNING: This monitor contains electrostatically sensitive devices. Use caution when handling
these components.
4-1 Disassembly
Cautions:1. Disconnect the monitor from the power source before disassembly.
2. To remove the Rear Cover, you must use the special opening jig tool.
Figure 1
Figure 2
Figure 3
Figure 4
7. When the hold-snap release, lift the Rear
Cover slightly to make sure it doesnÕt reengage while you release the snap on the
other side.
8. In a similar manner, Release the hold-snap on
the opposite side.
9. Pull the Rear Cover up off the monitor.
10. Using pinch-nose pliers or ling-nose pliers,
acrefully disconnect the Anode Cap from the
CRT.
Warning: Do not touch the Anode contact
on the CRT (High Voltage may
remain).
Note : If the hold-snap on the bottom of the
Front Cover is broken, secure the
cabinet by applying a 4x16 screw in
the extra holes on each side of the
cabinet.
4-1-2 Removing the CRT Socket PCB
1. Complete all previous steps.
2. Disconnect the CRT and Main PCB ground
wires between the CRT Socket PCB and
Shield Cover. (DP14LS only)
3. Lift up the Video Spring and remove the CRT
Socket PCB from the CRT.
4. Disconnect all connectors on the CRT Socket
PCB.
5. Using a solder iron, disconnect Ground (G2)
on the back of the Video Shield and remove
the Shield Cap.
6. Remove the screw on the front of the Shield
Socket.
7. Desolder the 4 tabs on the CRT Socket PCB
and remove Shield.
8. Place the Video PCB on a flat, level surface
that is protected from static electricity.
4 Disassembly and Reassembly
4-2 DP14L*/DP15L*
Figure 5
Figure 6
Figure 7
Figure 8
Figure 9
4-1-3 Removing the Main PCB
1. Complete all previous steps.
2. Disconnect the Degaussing Coil at GT601 and
GT602 on the Main PCB.
3. Disconnect all easily accessible ground wires
on the Main PCB and Bottom Chassis.
4. Disconnect the DY connector at the CN303
connector on the Main .
5. Using the jig, release the snaps (2) connecting
the Front Cover and Main PCB then lift up the
Bottom to separate the two Shield.
6. Remove the screws on the back and along
each side of the Bottom Chassis.
7. Carefully lift the Main PCB AssÕy and remove
the remaining ground wires.
8. Place the Main PCB AssÕy on a flat, level
surface that is protected from static electricity.
4-1-4 CRT Ass’y Disassembly
1. Complete all previous steps.
2. Straighten the Degaussing Coil Assembly
coated metal ties and lift the Coil AssÕy from
the CRT.
3. Remove the four corner screws and lift the
CRT up and away from the Front Cover
Assembly and place it on a padded surface.
Caution: Do not lift the CRT by the neck.
If you will be returning this CRT to
the monitor, be sure to place the CRT
face downward on a protective pad.
4 Disassembly and Reassembly
DP14L*/DP15L* 4-3
Figure 10
4-2 Reassembly
Reassembly procedures are in the reverse order of Disassembly procedures.
Memo
4 Disassembly and Reassembly
4-4 DP14L*/DP15L*
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) 14Ó
30 kHz to 61 kHz (automatic) 15Ó
Vertical: 50 Hz to 120 Hz (automatic)
Unless otherwise specified, adjust at the 800 x 600
mode (H : 53.7 kHz, V: 85 Hz) -14Ó/15Ó 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 - 14Ó,
25 ± 0.5 kV - 15Ó 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 - 15Ó .
5-1-1 (i) BRIGHTNESS AND CONTRAST
Unless otherwise specified, adjust brightness and
contrast buttons:
Brightness: Maximum
(press Å button until the LED is blink)
Contrast: Maximum
(press Å 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 (Ð) screwdriver: 1.5 mm
Non-metallic (Ð) 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
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. 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
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 DP14L*/DP15L*
MONITOR
INTERFACE
BOARD VER. 2.0
PC
SIGNAL
GENERATOR
7 PIN MINI DIN
CONNECTOR
SIGNAL CABLE
5V DC
ADAPTOR
PARALLEL CABLE
Figure 5-1. Setup 1, With Signal Generator
MONITOR
INTERFACE
BOARD VER. 2.0
PC
7 PIN MINI DIN
CONNECTOR
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: 267 mm (H) x 200 mm (V) for
15Ó, 255 mm (H) x 191 mm (V) for 14Ó
Adjust the horizontal position and vertical
position to within 4.0 mm of the center point of
the screen.
l A - B l ² 5.0 mm.
l C - D l ² 5.0 mm.
5-2-1 (a) HORIZONTAL MINIMUM SIZE ADJUSTMENT
CONDITIONS
Scanning frequency: 53.7 kHz/85 Hz
Display image: Crosshatch pattern
Brightness: Maximum
Contrast: Maximum
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
(15Ó) or 242 mm (14Ó) using H_SIZE MIN.
4. Adjust horizontal size to 267 mm (15Ó) or
255 mm (14Ó) 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.
5-2-1 (b) VERTICAL SIZE ADJUSTMENT
CONDITIONS
Scanning frequency: 53.7 kHz/85 Hz
Display image: Crosshatch pattern
Brightness: Maximum
Contrast: Maximum
Adjust the vertical size of the display pattern to
200 mm (15Ó) and 191 mm (14Ó).
(Tolerance: ± 3 mm.)
5-2-1 (c) HORIZONTAL POSITION ADJUSTMENT
CONDITIONS
Scanning frequency: 53.7 kHz/85 Hz
Display image: Crosshatch pattern
PROCEDURE
Center the test pattern on the raster.
5-2-1 (d) VERTICAL POSITION ADJUSTMENT
CONDITIONS
Scanning frequency: 53.7 kHz/85 Hz
Display image: Crosshatch pattern
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 (%)
Table 5-1. Standard Modes Linearity: 800 x 600/85Hz
Table 5-2. Other Modes Linearity: VGA, SVGA, XGA,
MAC, etc.
5 Alignment and Adjustments
DP14L*/DP15L* 5-3
5-2 Display Control Adjustments
C
A
DISPLAY AREA
EDGE OF BEZEL
B
D
Figure 5-3. Centering
Supported Timing Mode
Each block (14 %)
Difference between
adjacent blocks (5 %)
Standard Timing Modes
Each block (10 %)
Difference between
adjacent blocks (4 %)
2 x (Max – Min)
= x 100
Max + Min
5-2-3 Trapezoid Adjustment
CONDITIONS
Scanning frequency: 53.7 kHz/85 Hz
Display image: Crosshatch pattern
Make the the test pattern rectangular.
Figure 5-4. Trapezoid
5-2-4 Parallelogram Adjustment
CONDITIONS
Scanning frequency: 53.7 kHz/85 Hz (14Ó/15Ó)
Display image: 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 (Ð) buttons to
correct the display shape.
Figure 5-5. Parallelogram
5-2-5 Side Pincushion Adjustment
CONDITIONS
Scanning frequency: 53.7 kHz/85 Hz (14Ó/15Ó)
Display image: Crosshatch pattern
After pushing the Side Pincushion button once,
push the Increase (+) and Decrease (Ð) buttons to
straighten the sides of the test 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 (Ð) buttons to correct the Tilt.
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 (Ð) 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 (Ð) buttons to
correct the display shape.
5-2-9 Degauss
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.
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.
5 Alignment and Adjustments
5-4 DP14L*/DP15L*
2.2 mm 2.2 mm
| C1 |, | C2 | ≤ 2.0 mm, | D1 |, | D2 | ≤ 2.2 mm.
Figure 5-6. Pincushion
A
B
C
D
FRONT BEZEL
BACK RASTER
Figure 5-7. CRT Tilt Adjustment
2.2 mm 2.2 mm
C2
D2
D1
C1
2.2 mm
Before making adjustments, check that the video
signals are as follows:
Video : Analog, 0.7 Vp-p (at 75 ½ termination)
Sync : Separate TTL level
Unless otherwise specified, use 800 x 600 mode
signal (53.7 kHz/85 Hz) for adjustments.
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
5-3-2 Back Raster Color Adjustment
CONDITIONS
Measurement instrument: Color analyzer
Scanning frequency: 53.7 kHz/85 Hz
Display image: Back raster pattern
Brightness: Maximum
Contrast: Maximum
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 ÒyÓ coordinate to
0.298 ± 0.02.
4. Adjust the R_CUT to set the ÒxÓ 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.
5-3-3 Video Gain Adjustment
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
Figure 5-9. Full White Pattern
CONDITIONS
Measurement instrument: Color analyzer
Scanning frequency: 53.7 kHz/85 Hz
Display image: Full white pattern
Brightness: Maximum
Contrast: 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)
5 Alignment and Adjustments
DP14L*/DP15L* 5-5
5-3 Color Adjustments
1/3H-1/2H
1/3V-1/2V
FRONT BEZEL OPENING
BACK RASTER
GREEN WINDOW
FRONT BEZEL OPENING
BACK RASTER
WHITE WINDOW
5-3-5 White Balance Fine Adjustment
CONDITIONS
Measurement instrument: Color analyzer
Scanning frequency: 53.7 kHz/85 Hz
Display image: Full white pattern
X-Y coordinates: x = 0.283 ± 0.02
y = 0.298 ± 0.02
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: ÒHÓ 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.
5-3-9 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
(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.
5 Alignment and Adjustments
5-6 DP14L*/DP15L*
Red: x = 0.625 ± 0.015 y = 0.340 ± 0.015
Green: x = 0.310 ± 0.015 y = 0.592 ± 0.015
Blue: x = 0.150 ± 0.015 y = 0.063 ± 0.015
DP14L*/DP15L* 6-1
6 Troubleshooting
6-1 General 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.
6-1-1 No Picture
Check signal cable connection, H/V Sync input.
Check Timing mode (14”: 30~55kHz, 15”: 30~61kHz).
Check Cont,
Bright
key (all Max) and Screen VR (G2).
Check key components of secondary part. :
D406, D407, D408, D515, Q402, Q410, Q504, Rectifier
diodes (D608 ~ D612), IC101 (Vcc~GND)
Check key components of primary part. :
D601 ~ D607, FH601, IC601, TH602
Check SW601 (Power key)
Refer to 6-2-16 No Video.
Refer to 6-2-1 No Power.
Refer to 6-2-3 No Raster and 6-2-12 High Voltage Failure.
Refer to 6-2-17 Micom Failure.
Refer to 6-2-13 I2C Failure.
6 Troubleshooting
6-2 DP14L*/DP15L*
6-1-2 Shut Down
Check X-ray protection circuit. :
D502, D503, R510
Check key components of secondary part. :
D406, D407, D408, D515, IC101 (Vcc ~ GND)
Q402, Q504, Rectifier diodes
Check and replace IC601.
Refer to 6-2-1 No Power.
Refer to 6-2-3 No Raster and 6-2-12 High Voltage Failure.
Refer to 6-2-17 Micom Failure.
Refer to 6-2-13 I2C Failure.
6 Troubleshooting
DP14L*/DP15L* 6-3
6-1-3 No Video or Missing Colors
Are 0.7Vp-p video input on
CN202_2 R, G, B?
Check signal cable and generator.
Yes
No
Are proper waveform on
SK103’s R, G, B cathode?
Refer to 6-2-16 No Video.
Yes
No
Is G2 and heater voltage OK?
Check and replace SK103 and
some parts around it.
Yes
No
Change CRT and replace it.
Check white balance adjustment.
WAVEFORMS
22
19
19
46.4 V (SK103, G)
CH1 P-P = 46.4 V CH1 RMS = 38.16 V
22
1.016 V (CN202_2, #2,4,6)
CH1 P-P = 1.016 V CH1 RMS = 174.4 mV
WAVEFORMS
17
35.2 V (SK103, G1)
CH1 P-P = 35.2 V CH1 RMS = 80.84 V
25
4.96 V (IC201, #30)
CH1 P-P = 4.96 V CH1 RMS = 350 mV
Check signal cable connection, H/V Sync input.
Check Timing mode (14”: 30~55kHz, 15”: 30~61kHz).
Check Cont, Brit key (all Max) and Screen VR (G2).
6-1-4 Visible Retrace
Is G2 voltage (Screen VR) OK?
Adjust Screen VR to 0.4~0.6F/L (back
raster) at cont, bright all max.
Yes
No
Is V_sync input on Q301 base?
Check V_sync input line.
Yes
No
Is proper G1 pulse on SK103’s
G1 pin?
Check C306, C506, D504
Q301, Q501 and around parts.
Yes
No
Check and replace CRT.
25
17
6 Troubleshooting
6-4 DP14L*/DP15L*
6-1-5 Unsynchronized image
Are H/V sync input on IC201’s
Pins 30 and 31?
Check the connection of signal cable.
Refer to 6-2-12 High Voltage Failure.
Yes
Check H/V sync input line.
No
6-1-6 Misconvergence
Spec in?
(Center : 0.3 mm, Cornor : 0.4 mm)
Readjust Misconvergence.
Done
Yes
Change CRT and readjust
Miconvergence and color.
No
Refer to 6-2-17 Micom
Failure.
No
Are H/V sync input on IC401’s
Pins 1 and 2?
Yes
Check and replace IC401.
Yes
Check H/V sync input line.
No
Check and replace IC201.
No
WAVEFORMS
24
26
25
27
24
5.28 V (IC201, #31)
CH1 P-P = 5.28 V CH1 RMS = 1.218 V
25
4.96 V (IC201, #30)
CH1 P-P = 4.96 V CH1 RMS = 350 mV
26
5.48 V (IC401, #1)
CH1 P-P = 5.48 V CH1 RMS = 1.362 V
27
4.48 V (IC401, #2)
CH1 P-P = 4.48 V CH1 RMS = 284 mV
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