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COLOR TELEVISION RECEIVER
Chassis : KS3A(P)_50Hz(REV. 5)
Model : CW28C75VS8XXEC
CW28V53NS8XXEC
CW28V55VS8XXEC
WS24W63NS8XXEC
WS32W74NS8XXEC
WS32W76VS8XXEC
COLOR TELEVISION RECEIVER CONTENTS
1. Precautions
2. Reference Information
3. Specifications
4. Alignment and Adjustments
5. Troubleshooting
6. Exploded Views and Parts List
7. Electrical Parts List
8. Block Diagrams
9. Wiring Diagram
10. Schematic Diagrams
Alignment and Adjustments
4. Alignment and Adjustments
4-1 General Alignment Instructions
1. Usually, a color TV-VCR needs only slight 5. Avoid overload. Excessive signal from a
touch-up adjustment upon installation. Check sweep generator might overload the front-end
the basic characteristics such as height, of the TV. When inserting signal markers, do
horizontal and vertical sync and focus. not allow the marker generator to distort test
results.
2. Observe the picture for good black and white
details. There should be objectionable color 6. Connect the TV only to an AC power source
shading; if color shading is present, with voltage and frequency as specified on the
demagnetize, perform purity and convergence backcover nameplate.
adjustments described below.
7. Do not attempt to connect or disconnect any
3. Use the specified test equipment or its wires while the TV is turned on. Make sure
equivalent. that the power cord is disconnected before
replacing any parts.
4. Correct impedance matching is essential.
8. To protect against shock hazard, use an
isolation transformer.
4-2 Automatic Degaussing
A degaussing coil is mounted around the If the chassis or parts of the cabinet become
picture tube, so that external degaussing after magnetized, poor color purity will result. If
moving the TV should be unnecessary. But this happens, use an external degaussing coil.
the receiver must be properly degaussed upon Slowly move the degaussing coil around the
installation. faceplate of the picture tube and the sides and
front of the receiver. Slowly withdraw the coil
The degaussing coil operates for about 1 to a distance of about 6 feet before turning
second after the power is switched ON. If the power OFF.
set is moved or turned in a different direction,
the power should be OFF for at least 10 If color shading persists, perform the
minutes. following Color purity and Convergence
adjustments.
4-3 High voltage Check
CAUTION : There is no high voltage adjustment
on this chassis. The B+ power supply should be
+135 volts (with full color- bar input and normal
picture level).
1. Connect a digital voltmeter to the second
anode of the picture tube.
2. Turn on the TV. Set the Brightness and
Contrast controls to minimum (zero beam
current).
3. Adjust the Brightness and contrast controls to
both extremes. Ensure that the high voltage
does not exceed 32 KV under any conditions.
Samsung Electronics 4-1
Alignment and Adjustments
4-4 Dynamic Focus Adjustment
1. A dynamic focus adjustment should be done
after replacing the CRT PCB, FBT or CRT.
2. Input a crosshatch pattern.
3. Enter " STANDARD " in video mode.
4. Turn the Dynamic focus VR fully clockwise
(maximum).( )
5. Turn the Static focus VR fully
counterclockwise (maximum).( )
6. Slowly turn the static focus VR
counterclockwise. Adjust until the
STATIC FOCUS VR
vertical line in the middle of the screen H
has maximum clarity.( )
7. Slowly turn the dynamic focus VR (clockwise) DYNAMIC FOCUS VR
and adjust the 3rd horizontal line for V
maximum clarity.( )
SCREEN
8. Repeat 4-7, if necessary.
4-5 SCREEN Adjustment
1. Input Toshiba Pattern
2. Enter "Service Mode".(Refer to "Service Mode")
3. Select "G2-Adjust".
4. Set the values as example(Refer to page4-24).
ex) IBRM = 220
WDRV = 35
CDL = 220
COLR G B = 150 150 150
4-2 Samsung Electronics
Alignment and Adjustments
5. Turn the SCREEN VR until "MRCR G B" and "MRWDG" are green and those value are about 100.
(The incorrect SCREEN Voltage may result that "MRCR G B" and "MRWDG" should be red)
Note 1. When you do not have Toshiba Pattern, follow this method.
1. Set the TV on the condition that AV mode no signal(black)
2. Enter the "Menu" and set the mode to blue screen off.
3. Enter the "Service Mode".
4. Select " G2-Adjust".
5. Set the values as example(Refer to page4-24).
ex) IBRM = 220
WDRV = 35
CDL = 220
COLR G B = 150 150 150
6. Turn the SCREEN VR until the value of " MRCR G B" is about 120. Do not mind that
the "OSD" Color is red.
I After completing G2-Adjust, follow this procedure.
x Enter the "Video Adjust 1".
Choose any item in menu. (ex. Select "Red Cutoff")
Change the value of item you select, and recover the value.
For example, when the value of "Red Cutoff" is 127, change the value to 128 and restore
the value to 127.
If you do not follow this procedure, the picture may be abnormal.
For example, when the TV set is on, the picture becames brighter gradually.
Samsung Electronics 4-3
Alignment and Adjustments
4-6 E2PROM (IC902) Replacement
1. When IC902 is replaced, all adjustment data revert to the initial values.
So, all adjustment values when servicing should be readjusted.
2. After IC902 is replaced, connect the AC power supply cord.
3. Turn the power switch ON.
4. In stand-by, warm up the TV for at least 10 seconds.
5. Power on the TV.
4-7 White Balance Adjustment
I Equipment : Color-Analyzer (CA-100)
I Input Signal : Pattern signal (Toshiba pattern)
1. Select STANDARD from the menu.
2. Input an 100% White pattern.
3. Enter the "Service Mode". (Refer to "4-8 Service Mode")
4. Warm up the TV set at least for 30 minutes.
5. Input a Toshiba pattern signal.
6. Enter the "Video Adjust1".
- Adjust "Sub Contrast" so that Y (luminance) becomes 40 ft