Samsung CSH9839, CSH7839, CSH780 Alignment and Adjustments
6-1-1 Before Making Adjustments
6-1-1 (a) ORIENTATION
When servicing, always face the monitor to the
east.
6-1-1 (b) MAGNETIC FIELDS
Whenever possible, use magnetic field isolation
equipment such as a Helmholtz field to surround
the monitor. If a Helmholtz field is not available,
frequently degauss the unit under test.
Caution: Other electrical equipment may cause
external magnetic fields which may
interfere with monitor performance.
Use an external degaussing coil to limit magnetic
build up on the monitor. If an external degaussing
coil is not available, use the internal degaussing
circuit. However, do not use the internal
degaussing circuit more than once per 30 minutes.
6-1-1 (c) WARM-UP TIME
The monitor must be on for 30 minutes before
starting alignment. Warm-up time is especially
critical in color temperature and white balance
adjustments.
6-1-1 (d) SIGNAL
Analog, 0.714 Vp-p positive at 75 ohm, internal
termination
Sync: Separate/Composite
(TTL level negative/positive)
Sync-on-Green:
Composite sync 0.286 Vp-p negative
(Video 0.714 Vp-p positive)
6-1-1 (e) SCANNING FREQUENCY
Horizontal: 30 kHz to 96 kHz (Automatic)
Vertical: 50 Hz to 160 Hz (Automatic)
Unless otherwise specified, adjust at the
1024 x 768 mode (H: 68 kHz, V: 85 Hz) signals.
Refer to Table 3-1 on page 3-3.
6-1-1 (f) +B 220 V LINE ADJUSTMENT
Signal: 1024 x 768 mode (68 kHz/85 Hz)
Display image: Full white
Contrast: Maximum
Brightness: Maximum
6-1-1 (g) HIGH VOLTAGE ADJUSTMENT
Signal: 1024 x 768 mode (68 kHz/85 Hz)
Display image: Full white
Contrast: Maximum
Brightness: Maximum
Limit: 27 kV ± 0.5 kV (19”)
26 kV ± 0.5 kV (17”)
Measure the hight voltage level at the anode cap.
High voltage should be within the limit as above.
If the high voltage needs adjustment use the
following procedure.
PROCEDURE
1. Turn the power off and disconnect the AC line
cord from the power source.
2. Unsolder and remove VR501 on the Main
PCB.
3. Replace VR501 and adjust the high voltage to
the specification.
4. Using a soldering iron, melt the adjustment
cap on VR501 to prevent any movement.
6-1-1 (h) G2 (SCREEN) VOLTAGE ADJUSTMENT
Signal: 1024 x 768 mode (68 kHz/85 Hz)
Display image: Full white
Contrast: Maximum
Brightness: Maximum
Adjust the Screen VR of the FBT so that the G2
(Screen) Voltage for SDD is 600 V ± 10 V, for
Hitachi it is 600 V ± 10 V and for Toshiba it is
700 V ± 10 V.
6-1-1 (i) CENTER RASTER
Adjust VR401 so that the back raster comes to the
center when you apply a signal of 93 kHz/85 Hz.
CSH7839L/CSH9839L 6-1
6 Alignment and Adjustments
This section of the service manual explains how to make permanent adjustments to the monitor. Direction
is given for adjustment using the monitor Interface Board Ver. 2.0 and software (SoftJig).
6-1 Adjustment Conditions
Caution: Changes made without the SoftJig are saved only to the user mode settings. As such, the
settings are not permanently stored and may be inadvertently deleted by the user.
6-1-1 (j) BRIGHTNESS AND CONTRAST
Unless otherwise specified, adjust control
volumes:
Brightness: Maximum
Contrast: Maximum
6-1-2 Required Equipment
The following equipment may be necessary for
adjustment procedures:
6-1-2 (a) DISPLAY CONTROL ADJUSTMENT
1. Non-metallic (–) screwdriver: 1.5 mm
Non-metallic (–) screwdriver: 3 mm
2. Philips (+) screwdriver: 1.5 mm
3. Non-metallic hexkey: 2.5 mm
4. Digital Multimeter (DMM), or
Digital Voltmeter (DVM)
5. Signal generator, or
Computer with a video board that uses the
ET-4000 chipset (strongly recommended if
using Samsung DM 200 software) and that
displays: 1280 x 1024 @ 85 Hz, or 1600 x 1200
@ 85 Hz (maximum).
6. Personal computer
7. Required software: Softjig.exe from Samsung
which includes the cg17p.c data file
Samsung DM200, or DisplayMate for
Windows from Sonera Technologies
8. Interface Board Ver. 2.0 Code No.
BH81-90001K
9. Parallel communications cable (25-pin to
25-pin); Code No. BH81-90001H
10. Signal cable (15-pin to 15-pin cable with
additional 3-pin connector); Code No.
BH81-90001J
11. 5 V DC adapter, not supplied
Note: SoftJig Ass’y (includes items 8, 9 and 10)
Code No. BH81-90001L
6-1-2 (b) COLOR ADJUSTMENTS
1. All equipment listed in 6-1-2 (a), above
2. Color analyzer, or any luminance
measurement equipment
6-1-3 Connecting the SoftJig
Connect the monitor to the signal generator and/
or PC as illustrated in Figures 6-1 and 6-2.
Note: The signal cable connector which includes
the 3-wire cable must connect to the
monitor. If you use Setup 2 (PC only, no
signal generator) you can only make
adjustments to the signal timing available
on that computer system. To make
corrections to all factory timings requires
the use of an additional signal generator.
6-1-4 After Making Adjustments
After finishing all adjustments, test the monitor in
all directions. If, for example, the monitor does not
meet adjustment specifications when facing north,
reposition the monitor to face east and readjust.
This time, try for an adjustment closer to the ideal
setting within the tolerance range. Test the unit
again in all directions. If the monitor again fails to
meet specifications in every direction, contact
your Regional After Service Center for possible
CRT replacement.
6 Alignment and Adjustments
6-2 CSH7839L/CSH9839L
MONITOR
INTERFACE
BOARD VER. 2.0
PC
SIGNAL
GENERATOR
3-WIRE
CABLE
SIGNAL CABLE
5V DC
ADAPTOR
PARALLEL CABLE
Figure 6-1. Setup 1, With Signal Generator
MONITOR
INTERFACE
BOARD VER. 2.0
PC
3-WIRE CABLE
SIGNAL CABLE
PARALLEL CABLE
D-SUB
CONNECTOR
5V DC
ADAPTOR
Figure 6-2. Setup 2, Without Signal Generator
6-2-1 Centering
Centering means to position the center point of
the display in the middle of the display area.
Horizontal size and position and vertical size and
position control the centering of the display.
Adjust the horizontal size and vertical size to their
optimal settings: 352 mm (H) x 264 mm (V) - 19”,
306 mm (H) x 230 mm (V) - 17”.
1024 x 768 mode (68 kHz/85Hz)
Adjust the horizontal position and vertical
position to ≤ 4.0 mm of the center point of the
screen.
|A-B| ≤ 4.0 mm. |C-D| ≤ 4.0 mm.
Figure 6-3. Centering
6-2-1 (a) HORIZONTAL SIZE ADJUSTMENT
CONDITIONS
Scanning frequency: 68 kHz/85 Hz
Display image: Crosshatch pattern
Brightness: Cut-off
Contrast: Maximum
Click on the << or >> box next to H_SIZE to
adjust the horizontal size of the display pattern to
352 mm (19”), 306 mm (17”). (Tolerance: ± 3 mm.)
6-2-1 (b) VERTICAL SIZE ADJUSTMENT
CONDITIONS
Scanning frequency: 68 kHz/85 Hz
Display image: Crosshatch pattern
Brightness: Cut-off
Contrast: Maximum
Click on the << or >> box next to V_SIZE to
adjust the vertical size of the display pattern to
264 mm (19”), 230 mm (17”). (Tolerance: ± 3 mm.)
6-2-1 (c) HORIZONTAL POSITION ADJUSTMENT
CONDITIONS
Scanning frequency: 68 kHz/85 Hz
Display image: Crosshatch pattern
Brightness: Cut-off
Contrast: Maximum
Click on the << or >> box next to H_POSI to
center the horizontal image on the raster.
6-2-1 (d) VERTICAL POSITION ADJUSTMENT
CONDITIONS
Scanning frequency: 68 kHz/85 Hz
Display image: Crosshatch pattern
Brightness: Cut-off
Contrast: Maximum
Click on the << or >> box next to V_POSI to
center the vertical image on the raster.
6-2-2 Linearity
Linearity affects the symmetry of images as they
appear on the screen. Unless each row or column
of blocks in a crosshatch pattern is of equal size,
or within the tolerances shown in Tables 6-1 and
6-2, an image appears distorted, elongated or
squashed.
Table 6-1. Factory Preset Modes Linearity
Table 6-2. Other Modes Linearity: VGA, SVGA, XGA,
MAC, etc.
6-2-2 (a) HORIZONTAL LINEARITY ADJUSTMENT
CONDITIONS
Scanning frequency: 68 kHz/85 Hz
Display image: Crosshatch pattern
Brightness: Cut-off
Contrast: Maximum
6 Alignment and Adjustments
CSH7839L/CSH9839L 6-3
6-2 Display Control Adjustments
C
A
DISPLAY AREA
EDGE OF BEZEL
B
D
4 : 3 (19”)
4 : 3 (17”)
5 : 4 (19”)
5 : 4 (17”)
Horizontal: 20.5~23.5
Vertical : 20.5~23.5
Horizontal: 17.8~20.5
Vertical : 17.8~20.5
Horizontal: 19.18~22.07
Vertical : 20.5~23.5
Horizontal: 16.7~19.2
Vertical : 17.8~20.5
Supported Timing Mode
Each block (14 %)
Difference between
adjacent blocks (5 %)
Horizontal: Less than 1.10 mm
Vertical : Less than 1.10 mm
Horizontal: Less than 0.96 mm
Vertical : Less than 0.96 mm
Horizontal: Less than 1.03 mm
Vertical : Less than 1.10 mm
Horizontal: Less than 0.90 mm
Vertical : Less than 0.96 mm
4 : 3 (19”)
4 : 3 (17”)
5 : 4 (19”)
5 : 4 (17”)
Horizontal: 20.9~23.1
Vertical : 20.9~23.1
Horizontal: 18.2~20.1
Vertical : 18.2~20.1
Horizontal: 19.60~21.65
Vertical : 20.9~23.1
Horizontal: 17.1~18.9
Vertical : 18.2~20.1
Standard Modes Linearity
Each block (10 %)
Difference between
adjacent blocks (4 %)
Horizontal: Less than 0.88 mm
Vertical : Less than 0.88 mm
Horizontal: Less than 0.77 mm
Vertical : Less than 0.77 mm
Horizontal: Less than 0.82 mm
Vertical : Less than 0.88 mm
Horizontal: Less than 0.72 mm
Vertical : Less than 0.77 mm
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