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Alignment and Adjustments
4. Alignment and Adjustments
4-1 Preadjustment
4-1-1 Factory Mode 4-1-3 When CRT Is Replaced
1. Do not attempt these adjustments in the Video 1. Make the following adjustments AFTER set-
Mode. ting up after setting up purity and conver-
gence :
2. The Factory Mode adjustments are necessary
when either the EEPROM (IC902) or the CRT White Balance
is replaced. Sub-Brightness
Vertical Center
3. Do not tamper with the "Adjustment" screen Vertical Size
of the Factory Mode menu. This screen is Horizontal Size
intended only for factory use. Fail Safe (This adjustment must be the last
step).
4-1-2 When EEPROM (IC902) Is Replaced
2. If the EEPROM or CRT is replaced, set PVA to
1. When IC902 is replaced all adjustment data 40 (factory mode) and set SC as follows.
revert to initial values. It is necessary to
re-program this data. 14 inch : 0
20 inch : 9
2. After IC902 is replaced, warm up the TV for 21 inch : 9
10 seconds.
4-2 Factory/Service Mode
4-2-1 Procedure for the "Adjustment" Mode
4. Selection sequences for the all system:
1. This mode uses the standard remote control.
The Service Mode is activated by entering the DOWN or UP key:
following remote-control sequence : SCT>SBT>BLR>BLB>RG>GG>BG>VSL>
VS>VA>HS>SC>SDL>STT>SSP>PDL>
(1) DISPLAYFACTORY. NDL>PSR>NSR>AGC>VOL>LCO>TXP
(2) STAND-BY DISPLAY MENU MUTE 5. The VOLUME keys increase or decrease the
POWER ON. adjustment values (stored in the
non-volatile memory) when Adjustment Mode
2. The "SERVICE (FACTORY)" message will be is cancelled.
displayed. The Service Mode has four compo-
nents: ADJUST, OPTION and Reset. 6. Cancel the Adjustment Mode by re-pressing
the "FACTORY" or "Power OFF" keys.
3. Access the Adjustment Mode by pressing the
"VOLUME" keys ( Up or Down). The adjust-
ment parameters are listed in the accompany-
ing table, and selected by pressing the CHAN-
NEL keys (v ,w).
Samsung Electronics 4-1
Alignment and Adjustments
4-2-2 Main Adjustment Parameter
OSD F U N CT I ON R AN GE I N I T I A L D AT A RE MARK
SCT Su b Co n t ra s t 0 ~ 23 13
SBT Su b Bri g h t n e s s 0 ~ 23 9
BLR Bl a c k Le v e l o f fse t Blu e 0 ~ 15 9
BLB Bl a c k Le v e l o f fse t Red 0 ~ 15 7
RG R ed Gain 0 ~ 63 32
GG G re e n G a i n 0 ~ 63 25(Fix)
BG Bl u e G a i n 0 ~ 63 31
VSL Ve r t i ca l S lo p e 0 ~ 63 19
VS Ve r t i ca l Sh i f t 0 ~ 63 38
VA Ve r t i ca l A m p l i tu d e 0 ~ 63 40(Fix)
HS H o r i z o n t a l Sh i f t 0 ~ 63 30
SC S- Co r r e c t i o n 0 ~ 63 9
CD L Ca t h o d e Dri ve Le ve l 0 ~ 15 9
ST T Su b T i n t 0 ~ 7 3
SSP Su b Sh a rp n e s s 0 ~ 7 0
PDL P AL De l a y 0 ~ 15 15(Fix)
ND L NT SC De l a y 0 ~ 15 10
PSR P A L Su b c o l o R 0 ~ 23 2
NSR N T SC Su b c o l o R 0 ~ 23 5
AG C A u to m a t i c G a i n Co n t r o l 0 ~ 63 23
VO L Vo l u m e p re s e t t i n g 0 ~ 63 10
L CO SE CAM - L V i s i o n I F 0 ~ 1 0
T XP TTX Pos it ion 0 ~ 15 9
NOTE : PVS,PVA, PHS, parameters must be aligned using the 50Hz vertical-field rates.
4-2 Samsung Electronics
Alignment and Adjustments
4-2-3 Option Bytes
In the Service Mode, various can be selected via the Option Table. Example:
Option Table : xx xx xx xx
1 LNA ON
2 SYSTEM CZ
3 AUDIO MONO
4 JACK RCA
5 ZOOM NOR/ZOOM/16:9
6 AUTO POWER ON
7 SBL OFF
8 2nd SIF ON
9 HOTEL MODE OFF
10 BKS ON
Samsung Electronics 4-3
Alignment and Adjustments
4-2-4 RESET
The Reset Mode is used during factory inspection.
Function Reset:
1. Picture Custom
2. Auto Volume Off
3. Color System Auto (option)
4. Sound System D/K (option)
5. Blue Screen Off
6. Low Noise AMP Off (option)
7. Volume 10
8. CH. Skip Erased
9. CH. Lock Off
10. Timer Off
4-3 Other Adjustments
4-3-1 General 4-3-2 Automatic Degaussing
1. Usually, a color TV needs only slight touch- A degaussing coil is mounted around the pic-
up adjustment upon installation. Check the ture tube, so that external degaussing after
basic characteristics such as height, horizontal moving the TV should be unnecessary. But
and vertical sync and focus. the receiver must be properly degaussed upon
installation.
2. The picture should have good black and white
details. There should be no objectionable The degaussing coil operates for about 1 sec-
color shading; if color shading is present, per- ond after the power is switched ON. If the set
form the purity and convergence adjustments has been moved or turned in a different direc-
described below. tion, disconnect its AC power for at least 30
minutes.
3. Use the specified test equipment or its equiva-
lent. If the chassis or parts of the cabinet become
magnetized, poor color purity will result. If
4. Correct impedance matching is essential. this happens, use an external degaussing coil.
Slowly move the degaussing coil around the
5. Avoid overload. Excessive signal from a sweep faceplate of the picture tube and the sides and
generator might overload the front-end of the front of the receiver. Slowly withdraw the coil
TV. When inserting signal markers, do not to a distance of about 6 feet before removing
allow the marker generator to distort test power.
results.
6. Connect the TV only to an AC power source
with voltage and frequency as specified on the
backcover nameplate.
7. Do not attempt to connect or disconnect any
wires while the TV is turned on. Make sure
that the power cord is disconnected before
replacing any parts.
8. To protect against shock hazard, use an isola-
tion transformer.
4-4 Samsung Electronics
Alignment and Adjustments
4-3-3 High Voltage Check 4-3-6 Purity Adjustment
CAUTION: There is no high voltage adjustment on this chassis. 1. Warm up the receiver for at least 20 minutes.
The B+ power supply must be set to +125 volts (Full color bar input
and normal picture level). 2. Plug in the CRT deflection yoke and tighten
the clamp screw.
1. Connect a digital voltmeter to the second
anode of the picture tube. 3. Plug the convergence yoke into the CRT and
set in as shown in Fig. 4-2.
2. Turn on the TV. Set the Brightness and
Contrast controls to minimum (zero beam cur- 4. Input a black and white signal.
rent).
5. Fully demagnetize the receiver by applying an
3. The high voltage should not exceed 27.5KV. external degaussing coil.
4. Adjust the Brightness and contrast controls to 6. Turn the CONTRAST and BRIGHTNESS con-
both extremes. Ensure that the high voltage trols to maximum.
does not exceed 27.5KV under any conditions.
7. Loosen the clamp screw holding the yoke.
4-3-4 FOCUS Adjustment Slide the yoke backward or forward to pro-
vide vertical green belt. (Fig. 4-3).
1. Input a black and white signal.
8. Tighten the convergence yoke.
2. Adjust the tuning control for the clearest pic-
ture. 9. Slowly move the deflection yoke forward,
and adjust for the best overall green screen.
3. Adjust the FOCUS control for well defined
scanning lines in the center area of the screen. 10. Temporarily tighten the deflection yoke.
4-3-5 Cathode Voltage Adjustment 11. Produce blue and red rasters by adjusting the
low-light controls. Check for good purity in
(Screen Adjustment)
each field.
1. Connect CRT socket pin GK to an oscilloscope
12. Tighten the deflection yoke.
probe.
2. Input a gray scale pattern. (Use a pattern gen-
erator, PM5518)
3. Use the P mode key (on the remote control)
for the STANDARD picture.
4. Adjust the Screen VR (on the FBT) so that the
_
voltage on the oscilloscope becomes 120+2.5V
(See Fig. 4-1).
120 _ 2.5V
+
GND
14" :120 _ 2.5V
+
20, 21" : 120 _ 2.5V
+
Fig. 4-1
Samsung Electronics 4-5
Alignment and Adjustments
4 Pole Magnet 2 POLE
PURITY
6 Pole Magnet 2 Pole Magnet
Clamper
Screw ADJUST THE ANGLE
(VERTICAL LINES)
YOKE
CLAMP
SCREW
6 POLE
CONVERGENCE
4 POLE
CONVERGENCE
Fig. 4-2 Convergence Magnet Assembly
Vertical Green Belt
31m/m
Fig. 4-3 Center Convergence Adjustment
4-3-7 White Balance Adjustment
(a) Set up
1. Warm up the TV for at least 30 minutes in the
Aging Mode (OSD White). This mode is dis-
1
played by entering the following sequence:
DISPLAY FACTORY FACTORY
2. Input a Toshiba pattern.
2
(b) Low-Light Adjustment
1. Set SBT to 3.5