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ADJUSTMENT
Y Safety Precautions : Screen Voltage Adjustment
1. It is safe to adjust after using insulating transformer
between the power supply line and chassis input to Test Point : RK (Red Cathode of CPT Board)
prevent the risk of electric shock and protect the Adjust : Screen Control of FBT
instrument.
2. Never disconnect leads while the TV receiver is on.
3. Don't short any portion of circuits while power is on. 1) Tune the TV set to receive a color bar pattern.
4. The adjustment must be done by the correct appliances. 2) Press PSM (RED) button on remote controller. (standard
But this is changeable in view of productivity. picture)
5. Unless otherwise noted, set the line voltage to 3) Connect the probe of oscilloscope to the RK (Red
230Vac!10%, 50Hz. Cathode) of CPT Board.
4) Adjust Screen Volume of FBT so that the waveform is the
Y Test Equipment required same as below figure.
1. RF signal generator (with pattern generator)
2. DC Power Supply
3. Multimeter (volt meter) Horizontal
FlyBack Time
4. Oscilloscope Black level
5. Color analyzer
150 3V for 25" LG CPT
150 3V for 29" LG CPT
White level
: RF AGC (Automatic Gain Control) Adjustment GND for dc
Test Point : AGC TP (J2) The waveform of RK(Red Cathode) of CPT Board
Adjust : Remote Control
The RF AGC was aligned at the time of manufacture for
optimum performance over a wide range conditions. : Focus Adjustment
Readjustment of RF AGC should not be necessary unless
unusual local conditions exist, such as ; NOTE: This adjustment should be performed after warming
up for 10 minutes.
1) Channel interference in a CATV system.
2) Picture bending and/or color beats, which are unusually Test Point : Observing Display
due to excessive RF signal input when the receiver is too Adjust : Focus control of FBT
close to a transmitting tower or when the receiver is
connected to an antenna distribution system where the RF
signal has been amplified. In this case, the input signal 1) Tune the TV set to receive an inactive channel station.
should be attenuated (with pad or filter) to a satisfactory 2) Adjust the Focus control of FBT for best overall focus.
level.
3) Picture noise caused by "broadcast noise" or weak signal.
If the broadcast is "clean" and the RF signal is at least
1mV (60dBu), the picture will be noise free in any area.
Adjusting RF AGC to one end of rotation will usually cause a
relatively poor signal to noise ratio;
Adjusting to the other end of rotation will usually cause a
degradation of over load capabilities resulting in color beats or
adjacent channel interference.
Adjustment
1. Connect RF signal (60dB!1dB) and turn on the TV.
2. Press OK buttons on TV set and Remote Controller at the
same time to get into SVC mode.
3. Press Channel UP/DOWN button on the Remote Controller
several times to find AGC .
4. Press Volume UP/DOWN button until the AGC Voltage is
2.5!0.1V.
5. Press OK(Y) button to memorize the data.
- 1 -
: Deflection Data Adjustment (Line SVC-1) : White Balance Adjustment.(LINE SVC-0)
NOTE: To enter SVC mode, press "OK" buttons on both TV NOTE : This adjustment should be performed after screen
set and the Remote control at the same time. voltage adjustment.
1. Preparation for Deflection Adjustment 1) Tune the TV set to receive an 100% white pattern.
1) At SVC mode, press the Yellow colored button. 2) Press OK(Y) buttons on TV set and remote controller at
If the Remote Controller doesn't have the Yellow button, the same time to get into SVC mode.
you should use a Service Remote Control (105-201G) and 3) Press PSM (RED) button on remote controller. (Standard
press SVC button. picture)
And then, deflection data adjustment OSD (SVC1 mode) 4) Press Channel UP/DOWN button for desirous function
will be displayed. adjustment.
2) Press Channel UP/DOWN button for desirous function 5) Adjust VOL+ or VOL- button for GG031.
Adjustment. 6) Adjust VOL+ or VOL-button in each status of "Rg--"/"Bg--"
3) Press Volume UP/DOWN button to adjust the data. for X=282!8, Y=289!8 with color analyzer.
7) Press OK(Y) button to memorize the adjustment data.
2. Deflection Adjustment Procedure Status Adjustment Initial Data 25" LG 29" LG
1) Vertical Adjustment
RG R-Drive 35 32 32
Select VS and adjust until the mechanical center of CPT
and that of screen coincides and select VA and adjust to GG G-Drive 31 31 31
coincide the inner circle of screen with outer frame of CPT.
BG B-Drive 27 27 27
2) Horizontal Adjustment
Select HS and adjust until the mechanical center of CPT
and that of screen coincides.
3) Vertical S Correction Adjustment
Select SC and adjust until top-bottom side pincushion are
equal.
4) Press OK(Y) button to memorize the data.
3. Deflection Initial Setup Data
Status Default 25" LG 29" LG
VL 35 34 36
VS 20 31 38
VA 43 32 30
HS 31 33 30
SC 10 13 13
EW 39 37 47
EP 22 25 25
EC 23 09 30
ET 32 30 30
- 2 -
: OPTION Adjustment (SVC MODE:OPTION-1,
OPTION-2, OPTION-3)
NOTE: When the EEPROM has been replaced, the Option data
should be restored as the function of individual system OPTION Data COMB TILT AV2 SCART SYSTEM
and specification.
20 0 1 0 1 00
1) Press OK buttons on both TV set and Remote Controller at 21 0 1 0 1 01
the same time to get into SVC mode. 22 0 1 0 1 10
2) Press the Yellow button several times to find OPTION-1,
23 0 1 0 1 11
OPTION-2 or OPTION-3.
3) Input the correspond OPTION data referring to Table below 24 0 1 1 0 00
with the numeric buttons 0~9. 25 0 1 1 0 01
26 0 1 1 0 10
Table 1. OPTION 1 Function
27 0 1 1 0 11
Option Code Function Remark
28 0 1 1 1 00
00 BG+I+DK W/O RF 3.58(CF-, CZ-)
29 0 1 1 1 01
01 BG+I+DK+M with RF3.58(CT-, CD-)
SYSTEM 30 0 1 1 1 10
10 BG ONLY Single SYSTEM(CA-)
31 0 1 1 1 11
11 BG ONLY+DUAL South East Asian DUAL
32 1 0 0 0 00
0 PHONO JACK (AV1)
SCART 33 1 0 0 0 01
1 SCART JACK (AV1) with RGB Input
34 1 0 0 0 10
0 W/O AV2 (Front)
AV2 TOOL Option 35 1 0 0 0 11
1 with AV2 (Front)
36 1 0 0 1 00
0 W/O TILT Basic function for Chinese
TILT 37 1 0 0 1 01
1 with TILT and Australian Model
38 1 0 0 1 10
COMB 0 W/O DCF
Option 39 1 0 0 1 11
FILTER 1 with DCF
40 1 0 1 0 00
41 1 0 1 0 01
Table 2. Specifications for OPTION-1 data 42 1 0 1 0 10
OPTION Data COMB TILT AV2 SCART SYSTEM 43 1 0 1 0 11
0 0 0 0 0 00 44 1 0 1 1 00
1 0 0 0 0 01 45 1 0 1 1 01
2 0 0 0 0 10 46 1 0 1 1 10
3 0 0 0 0 11 47 1 0 1 1 11
4 0 0 0 1 00 48 1 1 0 0 00
5 0 0 0 1 01 49 1 1 0 0 01
6 0 0 0 1 10 50 1 1 0 0 10
7 0 0 0 1 11 51 1 1 0 0 11
8 0 0 1 0 00 52 1 1 0 1 00
9 0 0 1 0 01 53 1 1 0 1 01
10 0 0 1 0 10 54 1 1 0 1 10
11 0 0 1 0 11 55 1 1 0 1 11
12 0 0 1 1 00 56 1 1 1 0 00
13 0 0 1 1 01 57 1 1 1 0 01
14 0 0 1 1 10 58 1 1 1 0 10
15 0 0 1 1 11 59 1 1 1 0 11
16 0 1 0 0 00 60 1 1 1 1 00
17 0 1 0 0 01 61 1 1 1 1 01
18 0 1 0 0 10 62 1 1 1 1 10
19 0 1 0 0 11 63 1 1 1 1 11
- 3 -
Table 3. OPTION 2 Function OPTION Data HOTEL EYE CK FFI CHINA LANG.
Option Code Function Remark 30 0 1 1 1 1 0
0 0 W/O FFI/CK 31 0 1 1 1 1 1
0 1 W/O FFI 32 1 0 0 0 0 0
FFI/CK
1 0 W/O CK 33 1 0 0 0 0 1
1 1 With FFI/CK 34 1 0 0 0 1 0
0 W/O Chinese NICAM 35 1 0 0 0 1 1
CHINA
1 Chinese NICAM Chinese Models Only 36 1 0 0 1 0 0
0 Multi Language 37 1 0 0 1 0 1
LANG.
1 English Only 38 1 0 0 1 1 0
0 W/O HOTEL option 39 1 0 0 1 1 1
HOTEL for Buyer's request
1 for HOTEL 40 1 0 1 0 0 0
0 W/O EYE 41 1 0 1 0 0 1
EYE
1 With EYE Function 42 1 0 1 0 1 0
43 1 0 1 0 1 1
44 1 0 1 1 0 0
Table 4. Specifications for OPTION-2 data
45 1 0 1 1 0 1
OPTION Data HOTEL EYE CK FFI CHINA LANG.
46 1 0 1 1 1 0
0 0 0 0 0 0 0
47 1 0 1 1 1 1
1 0 0 0 0 0 1
48 1 1 0 0 0 0
2 0 0 0 0 1 0
49 1 1 0 0 0 1
3 0 0 0 0 1 1
50 1 1 0 0 1 0
4 0 0 0 1 0 0
51 1 1 0 0 1 1
5 0 0 0 1 0 1
52 1 1 0 1 0 0
6 0 0 0 1 1 0
53 1 1 0 1 0 1
7 0 0 0 1 1 1
54 1 1 0 1 1 0
8 0 0 1 0 0 0
55 1 1 0 1 1 1
9 0 0 1 0 0 1
56 1 1 1 0 0 0
10 0 0 1 0 1 0
57 1 1 1 0 0 1
11 0 0 1 0 1 1
58 1 1 1 0 1 0
12 0 0 1 1 0 0
59 1 1 1 0 1 1
13 0 0 1 1 0 1
60 1 1 1 1 0 0
14 0 0 1 1 1 0
61 1 1 1 1 0 1
15 0 0 1 1 1 1
62 1 1 1 1 1 0
16 0 1 0 0 0 0
63 1 1 1 1 1 1
17 0 1 0 0 0 1
18 0 1 0 0 1 0 Table 5. OPTION 3 Function
19 0 1 0 0 1 1 Option Code Function Option
Vol Game INCH.
Data
20 0 1 0 1 0 0 0 25"
INCH. 0 0 0 0
21 0 1 0 1 0 1 1 29"
1 0 0 1
22 0 1 0 1 1 0 0 W/O GAME
GAME 2 0 1 0
23 0 1 0 1 1 1 1 With GAME
3 0 1 1
24 0 1 1 0 0 0 0 Standard
VOL 4 1 0 0
25 0 1 1 0 0 1 1 South East Asia
5 1 0 1
26 0 1 1 0 1 0
6 1 1 0
27 0 1 1 0 1 1
7 1 1 1
28 0 1 1 1 0 0
29 0 1 1 1 0 1
- 4 -
PURITY & CONVERGENCE ADJUSTMENT
Caution:
Convergence and Purity have been factory aligned. Do not 5. Reconnect the internal degaussing coil.
attempt to tamper with these alignments.
However, the effects of adjacent receiver components, or 6. Position the beam bender locking rings at the 9 o'clock
replacement of picture tube or deflection yoke may require the position and the other three pairs of tabs (2,4 and 6 pole
need to readjust purity any convergence. magnets) at the 12 o'clock position.
DEFLECTION YOKE 6-POLE
6-POLE
PURITY &CONVERGENCE MAGNETS
MAGNES PURITY MAGNET(2-POL
MAGNET ASSEMBLY
6-POLE
,,,,
,,,, ,
,
,,,, 4-POLE
,,,,
,,,, ,
,,,, , ,,,,
,
,,,, ,
,,,, ,
,,,,
,,,,, X-AXIS YOKE MAGNET
,,,, , ,,,,
,,
,,,, , ,
,,,,
,, , POSITIONING
(L/R PURITY)
RUBBER
WEDGES PURITY MAGNET
4-POLE
GLASS CLOTH TAPE CONVERGENCE MAGNET ASSEMBLY
CONVERGENCE MAGNET ASSEMBLY
Y Purity Adjustment
This procedure DOES NOT apply to bonded yoke and picture 7. Perform the following steps, in the order given, to prepare the
tube assemblies. receiver for the purity adjustment procedure.
The instrument should be at room temperature (60 degrees F or
above) for six (6) hours and be operating at low beam current a. Face the receiver in the "magnetic north" direction.
(dark background) for approximately 20 to 30 minutes before
performing purity adjustments. b. Externally degauss the receiver screen with the television
power turned off.
CAUTION: Do not remove any trim magnets that may be
attached to the bell of the picture tube. c. Turn the television on for approximately 10 seconds to
perform internal degaussing and then turn the TV off.
1. Remove the AC power and disconnect the internal
degaussing coil. d. Unplug the internal degaussing coil. This allows the
thermistor to cool down while you are performing the purity
2. Remove the yoke from the neck of the picture tube. adjustment. DO NOT MOVE THE RECEIVER FROM ITS
"MAGNETIC NORTH" POSITION.
3. If the yoke has the tape version beam bender, remove it and
replace it with a adjustable type beam bender (follow the e. Turn the receiver on and obtain a red raster by increasing
instructions provided with the new beam bender) the red bias control (CW) and decreasing the bias controls
for the remaining two colors (CCW).
4. Replace the yoke on the picture tube neck, temporarily
remove the three (3) rubber wedges from the bell of the f. Attach two round magnets on the picture tube screen at 3
picture tube and then slide the yoke completely forward. o'clock and 9 o'clock positions, approximately one (1) inch
from the edge of the mask (use double-sided tape).
- 5 -
1.ADJUST YOKE Z-AXIS FIRST 2 .ADJUST BEAM BENDER 2 POLE
TO GET EQUAL BLUE MAGNET TO GET FOUR EQUAL
COLOR CIRCLES COLOR CIRCLES
MAGNETS
RED RED
8. Referring to above, perform the following two steps: 6. Reconnect the internal degaussing coil and apply AC power.
a. Adjust the yoke Z-axis to obtain equal blue circles.
b. Adjust the appropriate beam bender tabs to obtain correct 7. Turn the receiver on for 10 seconds to perform internal
purity (four equal circles). degaussing and then turn the receiver off again.
9. After correct purity is set, tighten the yoke clamp screw and 8. Unplug the internal degaussing-coil.
remove the two screen magnets.
9. Turn on the receiver, connect a signal generator to the VHF
10. Remove the AC power and rotate the receiver 180 degrees antenna terminal and apply a crosshatch signal.
(facing "magnetic south").
Caution: During the convergence adjustment procedure, be
11. Reconnect the internal degaussing coil. very careful not to disturb the purity adjustment tabs
are accidentally move, purity should be confirmed
12. Turn the receiver on for 10 seconds (make sure the receiver before proceeding with the convergence adjustments.
came on) to perform internal degaussing, and then turn the
receiver off. Note: Make sure the focus is set correctly on this instrument
before proceeding with the following adjustment.
13. Unplug the internal degaussing coil.
10. Converge the red and blue vertical lines to the green vertical
14. Turn on the receiver and check the purity by holding one (1) line at the center of the screen by performing the following
round magnet at the 3 o'clock and a second round magnet at steps (below TABLE).
9 o'clock position. If purity is not satisfactory, repeat steps 8 a. Carefully rotate both tabs of the 4-pole ring magnet
through 14. simultaneously in opposite directions from the 12 o'clock
position to converge the red and blue vertical lines.
15. Turn off the receiver and reconnect the internal degaussing b. Carefully rotate both tabs of the 6-pole ring magnet
coil. simultaneously in opposite directions form the 12 o'clock
position to converge the red and blue (now purple)
vertical lines with the green vertical line.
Y Convergence Adjustment
11. Converge the red and blue horizontal with the green line at
Caution: This procedure DOES NOT apply to bonded yoke and the center of the screen by performing the following steps.
picture tube assemblies. (below TABLE)
Do not use screen magnets during this adjustment a. Carefully rotate both tabs of the 4-pole ring magnet
procedure. Use of screen magnets will cause an simultaneously in the same direction (keep the spacing
incorrect display. between the two tabs the same) to converge the red and
blue horizontal lines.
1. Remove AC power and disconnect the internal degaussing b. Carefully rotate both tabs of the 6-pole ring magnet
coil. simultaneously in same direction (keep the spacing
between the two tabs the same) to converge the red and
2. Apply AC Power and set the brightness to the Picture Reset blue (now purple) horizontal lines with the green
condition. Set the Color control to minimum. horizontal line.
c. Secure the tabs previsouly adjusted by locking them in
3. Make horizontal line. place with the locking tabs on the beam bender.
4. Adjust the Red, Green and Blue Bias controls to get a dim
white line.
5. Restore the screen by removing the horizontal line.
- 6 -
RING ROTATION DIRECTION MOVEMENT OF RED
PAIRS OF BOTH TABS AND BLUE BEAMS
B B
OPPOSITE OR
R R
4
POLE
SAME B R OR B R
B B
OPPOSITE OR
R R
6
POLE
SAME B R OR B R
UP/DOWN ROCKING OF THE YOKE LEFT/RIGHT ROCKING OF THE YOKE
UP/DOWN ROCKING OF THE YOKE
CAUSES OPPOSITE ROTATION OF RED CAUSES OPPOSITE SIZE CHANGE YOKE
LEET/RIGHT ROCKING OF THE OF THE
AND BLUE RASTERS ROTATION OF RED
CAUSES OPPOSITE RED AND BLUE RASTERS CHANGE OF
CAUSES OPPOSITE SIZE
AND BLUE RASTERS THE RED AND BLUE RASTERS
GREEN
GREEN
ADJUSTMENT
VIEWING ADJUSTMENT RED
AREA BLUE RED VIEWING
AREA
RED
GREEN RED BLUE
BLUE RED
GREEN
RED BLUE
TV
SCREEN
GREEN
12. While watching the 6 o'clock positions on the screen, rock the 17. Temporarily place a rubber wedge at the 5 o'clock and 7
front of the yoke in a vertical (up/down) direction to converge o'clock positions to hold the horizontal position of the yoke.
the red and blue vertical lines. (Fig upper left) 18. Check the 3 o'clock and 9 o'clock areas to confirm that the
13. Temporarily place a rubber wedge at the 12 o'clock position red and blue vertical lines are converged. If the lines are not
to hold the vertical position or the yoke. converged, slightly offset the horizontal tilt of the yoke (move
14. Check the 3 o'clock and 9 o'clock areas to confirm that the red the temporary rubber wedges if necessary) to equally
and blue horizontal lines are converged. balance the convergence error of the horizontal lines at 6
If the lines are not converged, slightly offset the vertical tilt of the o'clock and 12 o'clock and the vertical lines at 3 o'clock and 9
yoke (move the rubber wedge if necessary) to equally balance the o'clock.
convergence error of the horizontal lines at 3 o'clock and 9 o'clock 19. Using a round magnet confirm purity at the center, right and
and the vertical lines at 6 o'clock and 12 o'clock. left sides and corners. See Purity Adjustment Procedure.
15. Place a 1.5 inch piece of glass tape over the rubber foot at 20. Reconfirm convergence and apply a 1.5 inch piece of glass
the rear of the 12 o'clock wedge. tape over the rubber foot at the rear of the 5 o'clock and the 7
16. While watching the 6 o'clock and 12 o'clock areas of the o'clock wedges.
screen, rock the front of the yoke in the horizontal (left to
right) motion to converge the red and blue horizontal lines.
(Fig. upper right)
- 7 -