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Alignment and Adjustments
5. Alignment and Adjustments
5-1 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.
5-2 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.
5-3 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 5-1
Alignment and Adjustments
5-4 RF AGC Adjustment
1. Turn to the strongest local station.
2. Turn the AGC control fully clockwise (VR101, on the MAIN board).
3. Adjust the AGC control until noise(snow)disappears from the screen.
5-5 FOCUS Adjustment
1. Input a black and white signal.
2. Adjust the tuning control for clearest picture.
3. Adjust the FOCUS control for well defined scanning lines in the center area of the screen.
5-6 SCREEN Adjustment
1. Turn to the ACTIVE channel.
2. Adjust the VR screen for a normal picture is (no blooming or flyback line).
3. Adjust the SCREEN control for well defined scanning lines in the center area of the screen.
5-7 Purity Adjustment
1. Warm up the receiver for at least 20 minutes.
2. Plug in the CRT deflection yoke. Tighten the clamp screw.
3. Plug the convergence yoke into the CRT and set it as shown in Fig. 5-1.
4. Input a black and white signal.
5. Fully demagnetize the receiver by using an external degaussing coil.
6. Turn the CONTRAST and BRIGHTNESS controls to maximum.
7. Loosen the clamp screw holding the yoke.
Slide the yoke backward or forward to produce a vertical green belt. (Fig. 5-2)
8. Tighten the convergence yoke.
9. Slowly move the deflection yoke forward.
Adjust for the best overall green screen.
10. Temporarily tighten the deflection yoke.
11. Produce blue and red rasters by adjusting the -low-light controls. Check for good purity in each field.
12. Tighten the deflection yoke.
5-2 Samsung Electronics
Alignment and Adjustments
4 Pole Magnet 2 POLE
PURITY
6 Pole Magnet 2 Pole Magnet
Clamper
Screw AD
(VE
YOKE
CLAMP
SCREW
6 POLE
CONVERGENCE
4 POLE
CONVERGENCE
Fig. 5 - 1 Convergence Magnet Assembly
Vertical Green Belt
31m/m
Fig. 5 - 2 Center Convergence Adjustment
Samsung Electronics 5-3
Alignment and Adjustments
5-8 Center Convergence Adjustment
1. Warm up the receiver for at least 20 minutes. 5. Adjust two tabs of 6-pole magnets:
Superimpose the red and blue lines with the
2. Adjust the BRIGHTNESS and CONTRAST green. Adjusting the angle affects the vertical
controls for a well-defined picture. lines, and rotating both magnets affects the
horizontal lines.
3. Adjust the two tabs of the 4-pole magnets:
Change the angle between them. 6. Repeat adjustments 2~4, if necessary.
Superimpose the red and the blue vertical
lines in the center area of the screen. 7. Since the 4-pole and 6-pole magnets interact,
the dot movement is complex (Fig. 5-3).
4. Turn both tabs at the same time, keeping the
angle constant: Superimpose the red and blue
horizontal lines in the center of the screen.
BLUE RED RED/BLUE GREEN
BLUE RED/BLUE
RED GREEN
4-Pole Magnet Movement 6-Pole Magnet Movement
Fig 5-3 Center Convergence Adjustment
5-4 Samsung Electronics
Alignment and Adjustments
5-9 Service Mode
1. Enter th Factory Mode. Press the remote-control keys in this sequence:
PICTURE OFF PICTURE OFF
DISPLAY P.STD MUTE
(RED KEY) (RED KEY)
2. Use the channel and volume keys (up/down)to move the cursor. Select an alignment parameter.
Use the volume keys(up/down)to adjust the value. Adjustment must be done separately for PAL,
SECAM, NTSC color systems. (As soon as the TV receives a signal, it switches to the correct broadcast
standard.) After adjustments are completed, press the picture off key to exit the Service Mode.
Press digit keys directly to change channel number.
Video Adjustment p1 Deflection p1
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00 Red Drive 031 00 P. V - Size +031
01 Blue Drive 031 01 P.VO - Shift +1
02 Green Drive 031 02 P.V - Lin +8
03 Red Cutoff 031 03 P.S - Correction 0
04 Blue Cutoff 031 04 Tilt +19
05 Green Cutoff 031 05 P. EW - Width +17
06 Sub Brightness 005 06 P. EW - Parabola -46
07 Sub Contrast 013 07 P. H - Shift -85
08 Sub Color 000 08 P. EW - Trapizium +40
09 Peak Drive Limit 063 09 P. EW - UpperCorner -2
10 P. YC Delay 010 10 P. EW - LowerCorner -2
11 Sub Tint 032 11 P. Hor - EHT -90
12 Gamma Correction 000 12 P. Ver - EHT -90
13 P. Bow -10
Option p1
Service Mode p1
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00 EPG On
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Video Adjustment
01 AV_LINK On Deflection
02 PAL Plus Off Option
03 12.8 : 9 (Q) On Reset
04 16 : 9 Wide Off
05 Dolby Prologic On
06 3D Sound Off
07 S - Audio Mute On
08 Blue Screen On
09 UHF Only Off
10 VGA Off
11 ATM ONE RUN On
Samsung Electronics 5-5
MEMO
5-6 Samsung Electronics