Akai LMH27CJSA User manual

Service Manual
AKAI
27”/ 30” Wide Screen
LCD Multi-Media Display
L
LM M- -H H2 27 7C CJ JS SA A
L
LM M- -H H3 30 0C CJ JS SA A

Table of Contents
1. Safety and Precautions …………………………………………………………1
2. Specifications.........................................................………………………………3
2.1 Specification for 27”............................……………………….…..3
2.2 Specification for 30”............................……………………….…..4
2.3 PC I/P Preset Timing Table.....................................................…..5
3. Connection & Applications……………………..............................................…..6
4. Controls Location ..........................................................................……………….8
5. Remote Control..............................................................................………………..9
6. Disassembly Instructions.......................…………………………….……..……..12
7. Block Diagram....................................................………………………………….18
8. Troubleshooting……………...............................................………………………19
8.1 Symptom Codes ( for Call center use). .............…………….…19
8.2 Flow Chart ( for Repair center use) ……….………....……….22
9. Electronic Circuit Description.....................................………………………..…27
10. Circuit Diagram...................................................…………………………..…….32
10.1 Main Board......................…………………….……………….32
10.2 Key , LED&IR Board .................……………………….…….42
10.3 Tuner Board…………………………………………………...43
10.4 I/O Board………………………………………………………44
11. PCB Layout...................................................…………………………………..…45
11.1 Main Board PCB.......……………………………..…………..45
11.2 Key , LED&IR Board PCB………..………………….…..….47
11.3 Tuner Board PCB……………………………………………..47
11.4 I/O Board PCB……………………………………………...…48
12. Electrical Parts List.....................................………………………………….…..49
13. Mechanical Disassembly....….............................................……………….……..57
14. Mechanical Parts List................................................……………………………59

1. Safety and Precautions
CAUTION
* The service of this LCD TV must be carried out by qualified persons only.
* Do not change any module unless the set is switched off.
CLEANING：Always disconnect unit from mains supply before attempting to clean it.
Use soft cloth moistened with soapy water, wipe gently. Do not use
solvents of abrasive materials.
SOME DO’S AND DON’T’S ON THE SAFE USE OF EQUIPMENT
This equipment has been designed and manufactured to meet European
safety standards but like any electrical equipment, care must be taken if
you are to obtain the best results and safety is to be assured.
Do read the operating instructions before you attempt to use the equipment.
Do ensure that all electrical connections (Including the mains plug, extension leads and
interconnections between pieces of equipment) are properly made in accordance with
the manufacturer’s instructions. Switch off and withdraw the mains plug when making
or changing connections.
Do use only the Power Cord and Power Supply (option) provided.
Do consult your dealer if you are ever in doubt of the installation, operating, or safety of
your equipment.
Don’t exert pressure on the LCD TV . This could break the panel .
Don’t continue to operate the equipment if you are in any doubt about it working
normally, or if it is damaged in any way. Switch off, withdraw the mains plug and consult
your dealer.
Don’t remove any fixed covers as this may expose dangerous voltages.
Don’t leave equipment switched on when it is unattended unless it is specifically stated
that it is designed for unattended operation or has a standby mode. Switch off using the
switch on the equipment and make sure that everyone knows how to do this. Special
arrangements may need to be made for infirm or handicapped people.
-1-

Don’t listen to headphones at high volume, as such use can permanently damage your
hearing.
Don’t obstruct the ventilation of the equipment, for example, with curtains or soft
furnishings. Overheating will cause damage and shorten the life of the equipment.
Don’t allow electrical equipment to be exposed to rain or moisture.
Above all
─Never let anyone push anything into holes, slots or any other opening as this could
result in a fatal electric shock.
─Never guess or take chances with electrical equipment of any kind.
─It is better to be safe than sorry!
WARNING：TO REDUCE THE RISK OF FIRE OR ELECTRIC SHOCK, DO NOT
EXPOSE THIS APPLIANCE TO RAIN OR MOISTURE. DANGEROUS
HIGH VOLTAGES ARE PRESENT INSIDE THE ENCLOSURE. DO NOT
OPEN THE CABINET. REFER SERVICING TO QUALIFIED
PERSONNEL ONLY.
-2-

2. Specifications
2.1 Specification for 27”:
ITEMS SPECIFICATION
Screen size 27” Wide TFT-LCD Panel (CMO)
Aspect Ratio 16：9
Resolution 1280 x 720 (Wide-XGA)
Contrast Ratio 500 : 1 (Typical)
Brightness 500 cd/m² (Typical)
Viewing Angle 170° (Hor.) / 170° (Vert.)
Response Time : Ton / Toff 15ms / 10ms
Display
OSD Language English, French, German, Spanish, Italian
TV Standard (CCIR) B/G, D/K, I and L/L’ (Multi-Europe)
Color System PAL / SECAM
Sound System NICAM / A2 (IGR)
TV Function
Teletext 10 Pages (FLOF / TOP )
Color System PAL / SECAM / NTSC
AV1 (In / Out) 21-pin SCART (RGB / Video) x 1
Video (Composite) x1
S-Video x1
Video I/O
AV2 (In) Component (YPbPr, YCbCr) x 1
( DTV system : 625p)
Signal I/P Analog : D-Sub 15 pin (detachable cable)
PnP compatibility DDC / 2B
I/P Frequency Analog: FH: 31kHz to 60kHz
F
v: 56Hz to 75Hz
Recommended Analog: 1024x768 (60Hz)
PC I/P
DTV ready (via D-sub 15pin) DTV System : 625p
Speaker (Built-in) : 10W+10W (rms)
Headphone Mini-jack for stereo (3.5 mm)
PC audio in
Audio In 1 / Out (R/L)
Audio I/O Audio I/O: L/R
Audio In 2 (R/L)
PIP under PC mode Yes
A.P.S. , Child-Lock Yes
Other Functions
VESA Panel Wall Mounting Holes 100mm x 100mm
Power Supply AC 100V~240V, 50/60Hz
Power
Power Consumption < 140W
Panel Tilt Forwards/ Backwards /Rotation -5°/ +15° / ±180°
Weight (net) 14.5 Kg (Without Accessories)
Accessories Remote Control , Batteriesx2 , AC cord , D-Sub Signal Cable, Operation Manual .
-3-

2.2 Specification for 30” :
ITEMS SPECIFICATION
Screen size 30” Wide TFT-LCD Panel (CMO)
Aspect Ratio 16：9
Resolution 1280 x 768 (Wide-XGA)
Contrast Ratio 500 : 1 (Typical)
Brightness 500 cd/m² (Typical)
Viewing Angle 170° (Hor.) / 170° (Vert.)
Response Time : Ton / Toff 15ms / 10ms
Display
OSD Language English, French, German, Spanish, Italian
TV Standard (CCIR) B/G, D/K, I and L/L’ (Multi-Europe)
Color System PAL / SECAM
Sound System NICAM / A2 (IGR)
TV Function
Teletext 10 Pages (FLOF / TOP )
Color System PAL / SECAM / NTSC
AV1 (In / Out) 21-pin SCART (RGB / Video) x 1
Video (Composite) x 1
S-Video x1
Video I/O
AV2 (In) Component (YPbPr, YCbCr) x 1
DTV system : 625p
Signal I/P Analog : D-Sub 15 pin (detachable cable)
PnP compatibility DDC / 2B
I/P Frequency Analog: FH: 31kHz to 60kHz
F
v: 56Hz to 75Hz
Recommended Analog: 1024x768 (60Hz)
PC I/P
DTV ready (via D-sub 15pin) DTV System : 625p
Speaker (Built-in) : 10W+10W (rms)
Headphone Mini-jack for stereo (3.5 mm)
PC audio in
Audio In 1 / Out (R/L)
AudioI/O Audio I/O: L/R
Audio In 2 (R/L)
PIP under PC mode Yes
A.P.S. , Child-Lock Yes
Other Functions
VESA Panel Wall Mounting Holes 100mm x 100mm
Power Supply AC 100V~240V, 50/60Hz
Power
Power Consumption < 150W
Panel Tilt Forwards/ Backwards /Rotation -5°/ +15° / ±180°
Weight (net) 15.2 Kg (Without Accessories)
Accessories Remote Control , Batteriesx2 , AC cord , D-Sub Signal Cable , Operation Manual .
-4-

2.3 PC I/P Preset Timing Table :
Analog Input
Mode No. Mode Name
Resolution
H.Freq. (kHz)
V.Freq. (Hz)
H. Polarity
V. Polarity
Pixel
CLK
(MHZ)
1 VGA 70Hz
640x350
31.469
70.087
+
- 25.175
2 VGA 60Hz
640x480
31.469
59.941
-
- 25.175
3 VGA 72Hz
640x480
37.861
72.81
-
- 31.5
4 VGA 75Hz
640x480
37.5
75.0
-
- 31.5
5 SVGA 56Hz
800x600
35.16
56.25
+
+ 36.0
6 SVGA 60Hz
800x600
37.876
60.317
+
+ 40.0
7 SVGA 72Hz
800x600
48.077
72.118
+
+ 50.0
8 SVGA 75Hz
800x600
46.875
75.0
+
+ 49.5
9 XGA 60Hz
1024x768
48.363
60.004
-
- 65.0
10 XGA 70Hz
1024x768
56.476
70.069
-
- 75.0
11 XGA 75Hz
1024x768
60.023
75.029
+
+ 78.75
12 MAC VGA
640x480
35.0
66.667
-
- 30.24
13 MAC VGA
832x624
49.725
74.550
-
- 57.283
14 US TEXT
720x400
31.469
70.087
-
+ 28.322
15 WXGA 60Hz
1280x768
47.733
60.042
-
- 80
-5-

SCART
V
IDEO
S-VIDEO
Y
Component
AC IN
3. Connection ＆Applications
Pb/Cb
Pr /Cr
-6-

NOTE:
zAudio out : The level of audio output cannot be changed using the volume , treble , and bass controls
on your TV . These connectors should be used with an external audio amplifier that can
be used to control the volume.
zVCR Recording: The main display must set to TV mode in order to use SCART to record a program using
a VCR .
zPIP sound : When using the PIP feature in PC mode , to hear the Sub display sound you must set the
sound source to “Sub” .
-7-
D-SUB CONNECTOR
PC AUDIO IN
HEAD PHONE
AUDIO IN 1 / OUT(R/L)
AUDIO IN 2 (R/L)
75Ohm AERIAL
INPUT SOCKET
PC
HEAD PHONE
VIDEO
AERIAL
SPEAKERS

4. Controls Location
The buttons control your TV’s basic features, including the on-screen menu. To use the more
advanced features, you must use the remote control.
POWER: turn on or turn off the LCD TV.
SOURCE: setuptheinputsource(PC,TV,SCARTVideo/SCARTRGB,
Video, S-Video, Component)
MENU: displaythemainmenu.
CHANNEL (down/up): change channels.
VOLUME (-/+): turn up or turn down the volume.
ASPECT RATIO: set up the ratio of display (Normal, Panscan, Zoom or Full.)
-8-
ASPECT RATIO VOLUME(-/+ ) CHANNEL(down/up) MENU SOURCE POWER
S
p
eake
r
S
p
eake
r
Remote sensor window
Aim the remote control
towards this region on the
TV.
Power indicator
A green indicator lights when the power is on
and a red indicator lights when in the standby
mode (the indicator will not light when the main
power is off).

5. Remote Control
The remote control pad works almost same as ordinary TV remote control that includes the
basic function needed while viewing a live video.
DISPLAY : Display the current source or program digits .
-9-

Summary of Control Buttons
-10-
Selectin
g
the Si
g
nal Source
TV
PC
SCART
VIDEO/S-V
COMPONENT
DISPLAY
Switch to the TV mode.
Switch to the PC mode.
Switch to the Video mode or RGB mode from SCART.
Switch to the Video mode from RCA socket or S-Video mode.
Switch to the Component mode (YPbPr or YCbCr).
Display the current source.
Menu Setting
MENU/ENTER
UP/DOWN
VOL- / VOL+
EXIT
Display the main on-screen menu or enter the next menu.
Press to select the item you want to adjust in the OSD menu.
Press to decrease or increase the value in the OSD control bar.
Exit from the menu.
Changing Channels
P- / P+
0 ~ 9
DISPLAY
RTN
Press P- or P+ to change Programs in TV mode or Teletext page in
TELETEXT mode.
To select programs directly in TV mode.
Display the current program digits.
Press to return to the previous program.
Sound Control
VOL+ / VOL-
MUTE
SOUND
Press to turn up or turn down the volume.
Press to switch the sound on or off.
Press to choose Stereo, Bilingual and Monaural broadcasts.
Teletext Control
TELETEXT
INDEX
HOLD
UPDATE
Press to show the Teletext Service. Press again to return to TV Viewing.
Press “ INDEX“ button to show the list of teletext contents.
Press “ HOLD“ button to stop the automatic page change.
Press “ UPDATE“ button to switch to TV while waiting for the next text page.

.
-11-
REVEAL
EXPAND
SUB-PAGE/TIME
RTN
Press “REVEAL“ button to display concealed information, such as
solutions of riddles or a quiz.
Press “EXPAND“ button to enlarge the top half or bottom half of the
Teletext page.
Press “SUB-PAGE/TIME“ button to access to the sub-page you
required.
Press to return to the previous viewed Teletext page.
PIP Control
ON / OFF
PIP Source
SIZE
POSITION
Press to watch one of the video sources on Sub-display, whilst in
PC mode. Press again to turn off the Sub-display.
Press to select the PIP window input source as :
Press ▲button : TV→SCART Video→SCART RGB→Video→
S-Video→Component
Press ▼button : Component→S-Video →Video→SCART RGB
→SCART Video→TV
To make the PIP window double, large or small.
Press to move the PIP window to: Top Left →Top Right→
Bottom Right →Bottom Left →Repeat.
Other Function
RESET
ARC
APC
SLEEP
SUB-PAGE/TIME
Reset to the original factory settings, such as theBrightness/Contrast/
Color Temp.
Set the picture window to Normal(4:3) → Panscan→Zoom→Full
(16:9)
To select Clear,Dark, or Nomal mode for picture control.
Press to select a preset time interval for automatic power off .
Press “Sub-Page/Time“ to display the digital clock in TV mode.
NOTE : When you set Main-display at 1280x768/1024x768 resolution of PC mode and Sub-display
YPbPr, the screen will appear “Not Available“. You should reduce the PC resolution to 800 X
600 or 640 X 480. The PIP function will then work.

6. Disassembly Instructions
1. Face down the LCD-TV :
Face down the LCD-TV on a smooth plane with a soft material to protect the panel
faceplate .
2. Tuner Board Removal :
Note: If only repair the Tuner Board , need not disassemble the
Base and Back Cover.
2.1 Remove Tuner Cover by pressing point D’and pushing point D toward the
rightdirection. (Indicatedas“
D”and “ D’ ” )
2.2 Remove 1 screw from the Tuner Board and pull out it along the slot .
( Indicated as “D’’ ”)
-12-
D’
D’’

3. Base Removal :
3.1 Remove 5 screws from the bottom of the Base. (Indicated as “A”)
3.2 Push upward and take the Base apart from the Neck. (Indicated as “Arrow” )
4. Neck Removal :
4.1Remove2screwsfromNeckCover. (Indicatedas“B ” )
4.2 Push 2 hooks on the inside of the Neck Cover by screw driver and take the Neck Cover
apartfromtheNeck. (Indicatedas“
B’ ” )
-13-
A
B’ B’

4.3 Remove 4 screws from the Neck and then take Neck apart from the Back Cover.
(Indicated as “
C”)
5. AV C o v e r ( I / O B o ard) Removal :
5.1Loosen2screws. (Indicatedas“E”)
5.2 Pull out the AV Cover (I/O Board) directly. ( Indicated as “
Arrow ”)
-14-

6. Back Cover Removal:
6.1 Remove 8 screws from the Back Cover . ( Indicated as “ F ” and “G”)
6.2 Take Back Cover apart from the LCD-TV.
7. Right / Left Side Covers Removal :
7.1 Remove 4 screws from 2 Slides of I/O Board & Right Side Cover. (Indicated as “ H”)
7.2 Remove 3 screws from the Power Case Assembly. (Indicated as “ J”)
7.3PulloutthePowerCaseAssemblydownwards. (Indicatedas“
Arrow”)
-15-

8. Main PCB Shield Removal :
8.1 Remove2screwsfromMainPCBShield. (Indicatedas“K ” )
8.2 Remove 2 Hexagonal screws from the D-Sub Connector. (Indicated as “K’ ”)
8.3 Take Main PCB Shield apart from Panel Bracket .
9. Main Bracket Removal :
9.1 Remove8screwsfromtheMainPCB. (Indicated“L“)
9.2 Take Main PCB apart from the Main Bracket .
-16-
K’

10.Panel Bracket Removal :
10.1 Remove 5 screws from the Panel Bracket . (Indicated as “ M ”)
10.2 Take Panel Bracket apart from the Front Cover .
-17-

PC VGA
Interlace
I010
P15V330
Component
Scart-Video
Video
S-Video
Scart-RGB
Progressive
Video
10W + 10W
Speaker
Headphone Jack
Scart Audio Out
Line-out (RCA)
7. Block Diagram
AC Input
100~240V
50 / 60Hz + 24V
+ 5V
+ 2.5V
+ 3.3V
I001
ADC
AD9883
-
140
I019
Scaler
TP6760
LCD
Panel
16:9
I012
MCU
SM59264C40
(SyncMOS)
Ke
y
Pad
INVERTER
I013
EEPROM: 24C16
Power
Module
LED & IR Pad
Remote Control
8 bit
I006
ADC
AD9883-110
24 bit Port B
24 bit Port A
I044
4:1 Audio Processor
MSP3410G
I021
Audio Amp.
LA4282
Scart Audio
Video/S-V/ Component Audio
PC Audio
Mono TV
UT01
TV – Tuner
FQ1216 MK3
SIF
I011
TT Decorder
SAA5264PS
I018
Decorder
SAA7118E
I014
LVDS
I034
P15V330
Component
Audio Out
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