COLOR TV
SERVICE MANUAL
CHASSIS : MC-007A
MODEL:CT-25/29Q47E/P/EN/EX
MODEL:CT-25/29Q46EN CF-29F84
CAUTION
BEFORE SERVICING THE CHASSIS,
READ THE SAFETY PRECAUTIONS IN THIS MANUAL.
CONTENTS
Contents ................................................................................................................. 2
Safety Precautions ............................................................................................3
Specifications ..................................................................................................... 4
Control Descriptions ........................................................................................ 5
Disassembly Instructions ............................................................................. 8
Adjustment Instructions ............................................................................... 9
Exploded View .................................................................................................. 14
Exploded View Parts List ..............................................................................15
Replacement Parts List ................................................................................ 16
SVC. Sheet ................................................................................................................
- 2 -
SAFETY PRECAUTIONS
IMPORTANT SAFETY NOTICE
Many electrical and mechanical parts in this chassis have special safety-related characteristics. These parts are identified by
the Schematic Diagram and Replacement Parts List.
in
It is essential that these special safety parts should be replaced with the same components as recommended in this manual to
prevent X-RADIATION, Shock, Fire, or other Hazards.
Do not modify the original design without permission of manufacturer.
Before returning the receiver to the customer,
General Guidance
always perform an AC leakage current check on the exposed
metallic parts of the cabinet, such as antennas, terminals, etc.,
to be sure the set is safe to operate without damage of
electrical shock.
An lsolation Transformer should always be used during
the servicing of a receiver whose chassis is not isolated from
the AC power line. Use a transformer of adequate power rating
as this protects the technician from accidents resulting in
personal injury from electrical shocks.
Leakage Current Cold Check(Antenna Cold Check)
With the instrument AC plug removed from AC source,
connect an electrical jumper across the two AC plug prongs.
Place the AC switch in the on positioin, connect one lead of
ohm-meter to the AC plug prongs tied together and touch other
ohm-meter lead in turn to each exposed metallic parts such as
antenna terminals, phone jacks, etc.
It will also protect the receiver and it's components from being
damaged by accidental shorts of the circuitary that may be
inadvertently introduced during the service operation.
If any fuse (or Fusible Resistor) in this TV receiver is blown,
replace it with the specified.
If the exposed metallic part has a return path to the chassis, the
measured resistance should be between 1MΩ and 5.2MΩ.
When the exposed metal has no return path to the chassis the
reading must be infinite.
When replacing a high wattage resistor (Oxide Metal Film
Resistor, over 1W), keep the resistor 10mm away from PCB.
An other abnormality exists that must be corrected before the
receiver is returned to the customer.
Keep wires away from high voltage or high temperature parts.
Due to high vacuum and large surface area of picture tube,
extreme care should be used in handling the Picture Tube.
Do not lift the Picture tube by it's Neck.
Leakage Current Hot Check (See below Figure)
Plug the AC cord directly into the AC outlet.
Do not use a line Isolation Transformer during this check.
Connect 1.5K/10watt resistor in parallel with a 0.15uF capacitor
between a known good earth ground (Water Pipe, Conduit, etc.)
and the exposed metallic parts.
X-RAY Radiation
Warning:
Measure the AC voltage across the resistor using AC
voltmeter with 1000 ohms/volt or more sensitivity.
Reverse plug the AC cord into the AC outlet and repeat AC
voltage measurements for each esposed metallic part. Any
voltage measured must not exceed 0.75 volt RMS which is
corresponds to 0.5mA.
In case any measurement is out of the limits sepcified, there is
possibility of shock hazard and the set must be checked and
repaired before it is returned to the customer.
The source of X-RAY RADIATION in this TV receiver is the
High Voltage Section and the Picture Tube.
For continued X-RAY RADIATION protection, the
replacement tube must be the same type tube as specified in
the Replacement Parts List.
To determine the presence of high voltage, use an accurate
high impedance HV meter.
Leakage Current Hot Check circuit
Adjust brightness, color, contrast controls to minimum.
Measure the high voltage.
AC Volt-meter
The meter reading should indicate
23.5 ¡ 1.5KV: 14-19 inch, 26 ¡ 1.5KV: 19-21 inch,
29.0 ¡ 1.5KV: 25-29 inch, 30.0 ¡ 1.5KV: 32 inch
If the meter indication is out of tolerance, immediate service
and correction is required to prevent the possibility of
premature component failure.
Good Earth Ground
such as WATER PIPE,
CONDUIT etc.
To Instrument's
exposed
0.15uF
METALLIC PARTS
1.5 Kohm/10W
- 3 -
SPECIFICATIONS
Note : Specification and others are subject to change without notice for improvement.
¡ Video input system:
PAL-B/G, D/K, I/I
SECAM-B/G, D/K/L/L’
NTSC M
SOUND IF : 33.4MHz (B/G)
32.9MHz (I/I)
32.4MHz (D/K,L)
34.4MHz (M)
40.4MHz (L’)
NTSC 4.43(AV)
¡ Intermediate Frequency (Unit : MHz)
VISION IF : 38.9MHz,33.9MHz(SECAM-L’)
COLOR IF : 34.47MHz(4.43)
¡ Power requirement : 110~240V, 50/60Hz
35.32MHz(3.58)
VIF-4.25000MHz
VIF-4.40625MHz
: NTSC-M
¡ Power consumption : 25”:125W
29”:135W
(
): SECAM
¡ CPT : True Flat CPT(Flatron)
¡ Tuning range
For TV
For CATV
NTSC
Band
B/G
D/K
I/I
VHF-Low
VHF-High
Ch2-4
Ch1-5
S1'-S3', S1
S2-S10,
S11-S20
S21-S41
Ch2-13
Ch5-12
Ch6-12
Ch4-13
Hyper
UHF
Ch21-69
Ch14-69
¡ Tuning system :
¡ Feature
:
Auto programme/Manual programme
SVM (Scanning Velocity Modulation)
Digital Eye
FVS
100 Programme memory
200 Programme memory(For CHINA)
Digital Comb Filter
Auto Sleep
Dynamic Focus
¡
Antenna input impedance : VHF/UHF 75 ohm, unbalanced
Programme Editing
PSM (Picture Status Memory)
CTI
Double Window Teletext (TOP/FLOF)
Turbo Search, Picture & Sound
ACMS
¡ OSD (On Screen Display) : MENU Type
¡ Voice coil impedance : 8 ohm
¡ Sound output : 12W+12W
Dual/Stereo : A2/NICAM(Option)
ARC (Zoom 1/ZOOM 2, 16:9¡Œ4:3)
1 TUNER PIP(Double Window PIP)
¡ External connection :
Front or
Head Phone Jack
S-VIDEO in
A/V in :1 pair
Scart 1(Full)
A/V in/out
Scart 2(Half)+Audio out
A/V in/out
In the Lock On state the TV can only be
operated by the Remote Controller.
If any button on the front panel is pressed,
"Child Lock" is displayed on the screen but
the button's function is not performed.
To cancel of this mode, select lock off with
menu button on remote controller only.
Child Lock :
Side
Back
¡ External In/Output
Audio-In:0.5Vrms¡ 3db,over 10Kohm
Audio-Out:0.5Vrms¡ 3db,below 1Kohm
Video-In/Out:1Vp-p¡ 3db,75ohm
R,G,B In:0.7Vp-p¡ 3db
- 4 -
DESCRIPTION OF CONTROLS
All the functions can be controlled with the remote control handset.
Some functions can also be adjusted with the buttons on the front
panel of the set.
POWER
Remote control handset
MUTE
10
1
2
Before you use the remote control handset, please install the bat-
teries. See the next page.
ARC
1
4
7
2
5
8
0
3
6
9
11
12
TV/AV
SOUND
1. POWER
switches the set on from standby or off to standby.
13
MENU PICTURE
2. NUMBER BUTTONS
switches the set on from standby or directly select a number.
TURBO
3
4
PR
3. MENU
VOL
VOL
OK
selects a menu.
PR
REW
PLAY
FF
4.
(Programme Up/Down)
D E
/
selects a programme or a menu item.
switches the set on from standby.
F / G (Volume Up/Down)
adjusts the volume.
adjusts menu settings.
OK
accepts your selection or displays the current mode.
5
REC
P/STILL
STOP
LIST
I/II
14
15
16
17
6
7
PSM
SSM
EYE/
MIX
TEXT/
PIP
8
9
?
M
i
TIME
STILL
REVEAL
SLEEP
5. VCR BUTTONS (option)
control a LG video cassette recorder.
SIZE
PR-
POSITION
9/4PIP
PR+ SWAP INPUT
6. SSM (Sound Status Memory)
recalls your preferred sound setting.
18
7. PSM (Picture Status Memory)
recalls your preferred picture setting.
8. EYE/ (option)
*
switches the eye function on or off.
(With teletext / PIP)
9. TELETEXT BUTTONS (option)
These buttons are used for teletext.
For further details, see the ÔTeletextÕ section.
EYE/
MIX
TEXT/
10. MUTE
?
M
TIME
REVEAL
SLEEP
switches the sound on or off.
9
i
11. ARC (Aspect Ratio Control)
changes the picture format.
Q.VIEW
18
12. TV/AV
selects TV or AV mode.
clears the menu / text from the screen.
switches the set on from standby.
(With teletext / Without PIP)
13. TURBO PICTURE / SOUND BUTTON
selects Turbo picture / sound.
- 5 -
14. LIST
displays the programme table.
15. I/II
selects the language during dual language broadcast (option).
selects the sound output.
16. PIP BUTTONS (option)
PIP
switches the sub picture on or off.
POWER
PR +/
selects a programme for the sub picture.
-
MUTE
10
12
1
2
3
SWAP
alternates between main and sub picture.
INPUT
selects the input mode for the sub picture.
SIZE
adjusts the sub picture size.
STILL
freezes motion of the sub picture.
POSITION
1
4
2
5
8
0
3
6
7
MENU
9
TV/AV
relocates the sub picture in clockwise direction.
9/4 PIP
switches on or off the 9 or 4 sub pictures.
PR
VOL
VOL
LIST
4
OK
17. SLEEP
Q.VIEW
PR
sets the sleep timer.
14
3
18
18. SWAP or Q.VIEW
returns to the previously viewed programme.
11
8
ARC
SSM
I/II
EYE/
COLOURED BUTTONS
These buttons are used for teletext (only TELETEXT models) or
programme edit.
SLEEP
PSM
15
6
7
PICTURE SOUND
TURBO
Battery installation
13
The remote control handset is powered by two AAA or AA type bat-
teries. To load the batteries, turn the remote control handset over
and open the battery compartment. Install two batteries as indicat-
+
ed by the polarity symbols ( and
ment.
-
) marked inside the compart-
(Without teletext / PIP)
AAA
AA
Note : To avoid damage from possible battery leakage, remove the
batteries if you do not plan to use the remote control handset for an
extended period of time.
- 6 -
1
3
4
2 6
5
1. MAIN POWER
switches the set on or off.
2. POWER/STANDBY INDICATOR
illuminates brightly when the set is in standby mode.
dims when the set is switched on.
3. MENU
selects a menu.
8
7
4. OK
accepts your selection or displays the current mode.
AV2
VIDEO
F / G (Volume Up/Down)
adjusts the volume.
adjusts menu settings.
L
MONO
AUDIO
R
(Programme Up/Down)
selects a programme or a menu item.
D E
/
switches the set on from standby.
5. EYE
adjusts picture according to the surrounding conditions.
6. REMOTE CONTROL SENSOR
7. AUDIO/VIDEO IN SOCKETS (AV2)
Connect the audio/video out sockets of external equipment to
these sockets.
8. HEADPHONE SOCKET
Connect the headphone plug to this socket.
- 7 -
DISASSEMBLY INSTRUCTIONS
Important note
Chassis Assy Removal
This set is disconnected from the power supply through the
converter transformer. An isolating transformer is necessary
for service operations on the primary side of the converter
transformer.
Grasp both side of Frame and pull it backward smoothly.
Speaker Assy Removal
1. Remove P1651 and P1652 connector from Main2 (Power/Def./
Sound-Amp) Board.
Back Cabinet Removal
2. Remove respective 6 screws for speaker on the front
cabinet. (Fig. 2-2).
Remove the screws residing on the back cabinet and carefully
separate the back cabinet from the front cabinet. (Fig. 2-1).
CPT Removal
PICTURE TUBE HANDLING CAUTION
Due to high vacuum and large surface area of picture tube, great
care must be exercised when handling picture tube. Always lift
picture tube by grasping it firmly around faceplate.
1. Pull out the CPT board from the CPT neck.
2. Place the front cabinet on soft material not to mar the front
surface or damage control knobs.
NEVER LIFT TUBE BY ITS NECK! The picture tube must not be
scratched or subjected to excessive pressure as fracture of
glass may result in an implosion of considerable violence which
can cause personal injury or property damage.
3. Remove 4 screws securing the picture tube mounting
brackets to the front cabinet.
4. Carefully separate CPT from the front cabinet.
CPT
board
Remove
Screws
POWER
PCB
A/V PCB
VCD PCB
STEREO
PCB
Fig. 2-1
Main PCB
Fig. 2-2
- 8 -
ADJUSTMENT INSTRUCTIONS
¡ Safety Precautions
¡ LÕ VCO Adjustment (For SECAM-LÕ MODEL)
1. It is safe to adjust after using insulating transformer between
the power supply line and chassis input to prevent the risk of
electric shock and protect the instrument.
Test Point
Adjust
: TP1
2. Never disconnect leads while the TV receiver is on.
3. Don't short any portion of circuits while power is on.
4. The adjustment must be done by the correct appliances.
5. Unless otherwise noted, set the line voltage to 230Vac¡
10%, 50Hz.
: VR122
1) Connect the measuring equipment to the Main Board as
shown in Fig.1.
5. The adjustment of TVshould be performed after warming up
for 15 minutes.
2) Set RF frequency and output level of RF SIGNAL
GENERATOR as shown Table 1.
3) Turn on S1,S3 and off S2.
2) Adjust VR122 so that the DC Voltage may be 2.4¡ 0.05Vdc.
¡ Test Equipment required
1. RF signal generator (with pattern generator)
2. DC Power Supply
¡
RF AGC (Automatic Gain Control) Adjustment
Test Point
Adjust
: TP 2(J15)
: VR121
3. Multimeter (volt meter)
4. Oscilloscope
5. Color analyzer
1) Input PAL-B/G 05 CH.
2) Connect Multimeter to TP2(J15),AGC adjustment point.
3) Adjust VR121 until the voltage of Multimeter becomes
2.5¡ 0.1V.
V
Multimeter or Oscilloscope
1
IC101
TDA4470
IC102(KI7805)
¡ Screen Voltage Adjustment
R108
9V
R144
0.01uF
Test Point
Adjust
: CPT Face
22
TP1(VCO)
JP1
7
38.9MHz
34.25MHz
(B/G,D/K,I,L)
(SECAM-L')
Power-
Supply
: Screen Control of FBT
5V
L104
13
14
4.7 Kohm
Q122
JP2
100 ohm
1) Tune the RF Modulator to receive a PAL or SECAM signal.
2) Press MIX button on remote controller for Service to get into
the Screen Adjust Mode.
S3
S1
100 ohm
VR122
3) Adhere the Color Analyzer on the White window of CPT
face.
JP3
S2
4) Adjust Screen Volume of FBT so that the luminance of White
window is 12¡ 1 FL.
Fig. 1 : Connection Diagram of Equipment for PIF Adjustment
¡ Focus Adjustment
¡
PIF (Picture Intermediate Frequency) Adjustment
Test Point
Adjust
: Observing Display
: Focus control of FBT
Test Point
Adjust
: TP1
: L104
1) Tune the TV set to receive a digital pattern.
2) Adjust the upper Focus volume of FBT for the best focus of
vertical line B.
1) Connect the measuring equipment to the Main Board as
shown in Fig.1.
3) Adjust the lower Focus volume of FBT for the best focus of
area A.
4) Repeat above step 2) and 3) for the best overall focus.
2) Set RF frequency and output level of RF SIGNAL
GENERATOR as shown Table 1.
3) Turn off S1 and S3 and on S2.
4) Adjust L104 so that the DC voltage may be 2.4¡ 0.05Vdc.
Modulation
OFF
Adjust
L104
Output level
10mVp-p
System
Frequency
38.9MHz
B/G,D/K/I,SECAM-L
SECAM-LÕ
OFF
VR122
10mVp-p
34.25MHz
(Table 1)
- 9 -
Adjust so that middle portion of the outermost left and right
vertical line looks like parallel with vertical lines of the CPT.
A
B
EC (East-west Coner)
Adjust so that the vertical line at every 4 corners of the
screen looks like parallel with the vertical lines of the CPT.
ET (East-west Trapezium)
Adjust to make the length of top horizontal line same with
it of the bottom horizontal line.
POP (POP Position)
Adjust until the distance between POP and main picture
Fig. 2
becomes about 1mm.
¡ Deflection Data Adjustment (Line SVC-2)
Menu
Range
29Ó Flat
29Ó S-Flat
NOTE : How to enter into the Line Service Mode with a remocon.
VS
VA
VL
0600H~0900H
0050H~00CFH
0025H~00BFH
0000H~009FH
0000H~003FH
0400H~0EFFH
0700H~08FFH
06E0H~0840H
06A0H~0AFFH
0790H~08E0H
07D2
0095
0001
00D9
001E
0A9D
07FF
0787
0815
0850
000B
1.Power off.
2.Press the Red button.
3.Press the Green button.
4.Press the Yellow button.
5.Press the Cyan button.
6.Press the OK button.
7.Power On.
SC
HS
EW
ET
EP
ES
EC
1. Preparation for Deflection Adjustment
1) At SVC mode, press the Yellow colored button the SVC
remocon.
And then,deflection data adjustment OSD(SVC2 mode) will
be displayed.
2) Press Channel UP/DOWN button for desirous function
Adjustment.
POP P 0790H~08E0H
(Table 2)
3) Press Volume UP/DOWN button to adjust the data.
4) Tune the TV set to receive a PAL B/G Digital pattern.
VL (Vertical Linearity)
Adjust so that the boundary line between upper and lower
¡ White Balance Adjustment.(LINE SVC 1)
half is in accord with geometric horizontal center of the CPT.
NOTE : This adjustment should be performed after screen
voltage adjustment.
VA (Vertical Amplitude)
Adjust so that the circle of a digital circle pattern may be
located within the effective screen of the CPT.
1) Tune the TV set to receive an 100% white pattern.
2) Press the Yellow button on remote controller in the SVC
Mode.
SC (Vertical “S” Correction)
Adjust so that all distance between each horizontal lines
are to be the same.
3) Press PSM (RED) button on remote controller. (Standard
picture)
4) Press PR+ or PR- button for desirous function adjustment.
5) Adjust Low Light status of CR and CB with VOL+ or VOL-
at CG:50 until X=268¡ 8,Y=273¡ 8.
VS (Vertical Shift)
Adjust so that the horizontal center line of a digital circle
pattern is in accord with geometric horizontal center of
the CPT.
6) Adjust High Light status of RG and BGB with VOL+ or
VOL- at CG:370 until X=268¡ 8,Y=273¡ 8.
7) Repeat above step 5) and 6) until each status of High Light
and Low Light for X=288¡ 8,Y=295¡ 8 with color
HS (Horizontal Shift)
Adjust so that the vertical center line of a digital circle pattern
o
analyzer(color temperature 9000K).
is in accord with geometric vertical center of the CPT.
EW (Horizontal Width)
Adjust to that a digital circle pattern looks like exact circle.
- 10 -
Menu
Range
DATA
50
CR
CG
CB
RG
GG
BG
0 ~ 511
0 ~ 511
0 ~ 511
0 ~ 511
0 ~ 511
0 ~ 511
50
50
370
370
370
(Table 3)
¡ SVC Data & PSM,SSM Data.
Table 1. ABL Data (LINE SVC-3)
Menu
Range
29Ó Flat
29Ó S-Flat
DVCO
IBRM
0~1FFH
0~3FFH
0~7FFH
0~1FFH
0~1FFH
00C8
0190
0065
000B
0007
0008
0005
0003
0001
00F0
0158
WDRM
BCLTH
BCLTM
BCLGA
SVGA
SVDEL
SVD1
LDLY
HBST
0~01FF
0~01FF
HBSO
Table 2. SOUND PRE-SCALER (LINE SVC-4)
Menu
Range
DATA
FP
NP
0~127
0~127
0~127
0~127
0~127
0011
0045
001E
0042
0042
SP
S1 VOL
S2 VOL
Table 3. PSM Data
Mode
STANDARD DYNAMIC MILD GAME
CONTRAST
BRIGHT
90
50
50
50
100
55
60
60
40
40
50
60
40
30
COLOR
60
SHARPNESS
60
- 11 -
¡ OPTION Adjustment (LINE-SERVICE OPTION)
Table 4. OPTION Function
OPTION
GAME
TEXT
TOP
1
0
Menu
GAME
TEXT
TOP
X
X
X
ACMS
CH+AU
EYE
Australia Only
Option 1
China,Australia
EYE
X
TURBO
SCART
A2 ST
I II SV
MONO
VOL
Turbo Search
SCART
X
X
STEREO
X
I/II
X
X
MONO
Middle East Africa,India VOL.
H/Phone
Normal VOL.
Option 2
H-PH
DGS
Degaussing
TILT
X
TILT
200PRO
AV2
China Only
Back:JACK(2EA)
HOTEL
X
Back:JACK(1EA)
X
HOTEL
KEY
Option 3
Option 4
SYS
M-VOL
OSD
T-LAN
- 12 -
MEMO
- 13 -
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