Sharp LC-20B5M Schematic

1st Edition
SERVICE MANUAL
LCD COLOUR TELEVISION
LC-20B5M
MODEL
In the interests of user-safety (Required by safety regulations in some countries) the set should be re­stored to its original condition and only parts identical to those specified should be used.
» IMPORTANT SERVICE SAFETY PRECAUTION ........................................................................................2
» SPECIFICATIONS ........................................................................................................................................4
» OPERATION MANUAL .................................................................................................................................5
» DIMENSIONS ...............................................................................................................................................7
» REMOVING OF MAJOR PARTS ..................................................................................................................8
» ADJUSTING PROCEDURE OF EACH SECTION .....................................................................................13
» TROUBLE SHOOTING TABLE...................................................................................................................24
» CHASSIS LAYOUT .....................................................................................................................................28
» BLOCK DIAGRAM......................................................................................................................................30
» OVERALL WIRING DIAGRAM ...................................................................................................................32
» DESCRIPTION OF SCHEMATIC DIAGRAM .............................................................................................34
» SCHEMATIC DIAGRAM .............................................................................................................................35
» PRINTED WIRING BOARD ASSEMBLIES................................................................................................75
» REPLACEMENT PARTS LIST....................................................................................................................86
» PACKING OF THE SET ............................................................................................................................101
LC-20B5M
Page
SHARP CORPORATION
LC-20B5M
2
2
IMPORTANT SERVICE SAFETY PRECAUTION
Ë
Service work should be performed only by qualified service technicians who are thoroughly familiar with all safety checks and the servicing guidelines which follow:
WARNING
1. For continued safety, no modification of any circuit should be attempted.
2. Disconnect AC power before servicing.
CAUTION: FOR CONTINUED PROTECTION AGAINST A RISK OF FIRE REPLACE ONLY WITH SAME TYPE F3701 (2A, 250V), F3702 (1.25A, 250V), F6700 (1.25A, 250V), F6701 (1.25A, 250V), F6702 (1.25A, 250V), F6703 (1.25A, 250V) AND F6704 (1.25A, 250V) FUSE.
BEFORE RETURNING THE RECEIVER (Fire & Shock Hazard)
Before returning the receiver to the user, perform the following safety checks:
1. Inspect all lead dress to make certain that leads are not pinched, and check that hardware is not lodged between the chassis and other metal parts in the receiver.
2. Inspect all protective devices such as non-metallic control knobs, insulation materials, cabinet backs, adjustment and compartment covers or shields, isolation resistor-capacitor networks, mechanical insulators, etc.
3. To be sure that no shock hazard exists, check for leakage current in the following manner.
Plug the AC cord directly into a 110~240 volt A C outlet, and connect the DC power cable into the receiver's DC jack. (Do not use an isolation transformer for this test).
Using two clip leads, connect a 50k ohm, 10 watt resistor paralleled by a 0.15µF capacitor in series with all exposed metal cabinet parts and a known earth ground, such as electrical conduit or electrical ground connected to an earth ground.
Use an AC voltmeter ha ving with 5000 ohm per volt, or higher, sensitivity or measure the AC voltage drop across the resistor.
Connect the resistor connection to all exposed metal parts having a return to the chassis (antenna, metal cabinet, screw heads, knobs and control shafts, escutcheon, etc.) and measure the AC voltage drop across the resistor. All checks must be repeated with the AC cord plug connection reversed. (If necessar y, a nonpolarized adaptor plug must be used only for the purpose of completing these checks.) Any reading of 0.75V peak (this corresponds to 0.5 mA. peak AC.) or more is excessive and indicates a potential shock hazard which must be corrected before returning the monitor to the owner.
DVM
AC SCALE
50k ohm
10W
0.15 µF
TEST PROBE
TO EXPOSED METAL PARTS
CONNECT TO KNOWN EARTH GROUND
234567890123456789012345678901212345678901234567890123456789012123456789012345678901234567890121
SAFETY NOTICE
Many electrical and mechanical parts in LCD television have special safety-related characteristics. These characteristics are often not evident from visual inspection, nor can protection afforded by them be necessarily increased by using replacement components rated for higher voltage, wattage, etc. Replacement parts which have these special safety characteristics are identified in this manual; electrical
and shaded areas in the
Schematic Diagrams.
For continued protection, replacement parts must be identical to those used in the original circuit. The use of a substitute replacement parts which do not have the same safety characteristics as the factory recommended replacement parts shown in this service manual, may create shock, fire or other hazards.
components having such features are identified by “ å”
234567890123456789012345678901212345678901234567890123456789012123456789012345678901234567890121
Replacement Parts Lists and
2
LC-20B5M
Precautions for using lead-free solder
1 Employing lead-free solder
"All PWBs" of this model employs lead-free solder. The LF symbol indicates lead-free solder, and is attached on the PWBs and service manuals. The alphabetical character following LF shows the type of lead-free solder. Example:
L Fa
Indicates lead-free solder of tin, silver and copper.
2 Using lead-free wire solder
When fixing the PWB soldered with the lead-free solder, apply lead-free wire solder. Repairing with conventional lead wire solder may cause damage or accident due to cracks. As the melting point of lead-free solder (Sn-Ag-Cu) is higher than the lead wire solder by 40°C, we recommend you to use a dedicated soldering bit, if you are not familiar with how to obtain lead-free wire solder or soldering bit, contact our service station or service branch in your area.
3 Soldering
As the melting point of lead-free solder (Sn-Ag-Cu) is about 220°C which is higher than the conventional lead solder by 40°C, and as it has poor solder wettability, you may be apt to keep the soldering bit in contact with the PWB for extended period of time. However, Since the land may be peeled off or the maximum heat-resistance temperature of parts may be exceeded, remov e the bit from the PWB as soon as you confirm the steady soldering condition. Lead-free solder contains more tin, and the end of the soldering bit may be easily corroded. Mak e sure to turn on and off the power of the bit as required. If a different type of solder stays on the tip of the soldering bit, it is allo y ed with lead-free solder. Clean the bit after every use of it. When the tip of the soldering bit is blackened during use, file it with steel wool or fine sandpaper.
Be careful when replacing parts with polarity indication on the PWB silk.
Lead-free wire solder for servicing
Part No, Description Code ZHNDAi123250E J φ0.3mm 250g(1roll) BL ZHNDAi126500E J φ0.6mm 500g(1roll) BK ZHNDAi12801KE J φ1.0mm 1kg(1roll) BM
3
LC-20B5M
SPECIFICATIONS
ITEMS
LCD panel Number of pixels 921,600 dots Video colour systems World multi system
TV Standard (CCIR) I/DK/M/BG TV Tuning System Auto preset tuning
TV function STEREO/BILINGUAL NICAM-BG, I, DK/A2 stereo-BG
AUTO PRESET Yes
CATV S1~S41 ch. Hyper Band 4-LINE DIGITAL COMB FILTER Yes Brightness 450 cd/m Lamp life 60,000 hours* Viewing angles H: 170° V: 170° Audio output 2.1 W 2× Speakers 5.7 cm ø, 2 pcs.
AV1 Composite Video, S-Video, Audio
AV2 IN/OUT Composite Video, Audio IN/Composite Video, Audio OUT Terminals
Image File Format JPEG files complying with DCF format OSD LANGUAGE English/Chinese/Arabic Power requirement DC 12 V, AC 110–240 V, 50/60 Hz Power Consumption For Asia
Weight 9.2 kg w/o accessories Accessories Remote control, Batteries ( 2), Antenna cable, AC adapter,
* The typical period of time after which the lamp’s power output will have decreased by about half, given that the AQUOS is used continuously
in a 25°C room under standard lighting and brightness conditions.
As a part of policy of continuous improvement, SHARP reserves the right to make design and specification changes for the LCD TV set improvement without prior notice. The performance specification figures indicated are nominal values of production units. There may be some deviations from these values in individual units.
COMPONENT Y, PB, PR/Audio Headphone jack 3.5 mm ø jack (Front) PC Card Slot PC Card Type II (PC Card Adapter)
MODEL
LC-20B5M
19.7" (50 cm) Advanced Super View & BLACK TFT LCD
2
63 W (1.2 W Standby): AC 230 V (With AC adapter)
For Australia
65 W (1.2 W Standby): AC 230 V (With AC adapter)
55W : DC 12 V
AC cord,
Cable holder, Operation manual
×
4
OPERATION MANUAL
MAIN POWERMENUVOL
( )
/
( )
TV/VIDEOCH
( )
/
( )
LC-20B5M
Upper control panel
Part Names of Main Unit
Controls
NOTE
TV/VIDEO, CH (
)/(
), VOL (–)/(+) and MENU on the main unit have the same functions as the same buttons on the remote control.
Fundamentally, this operation manual provides a description based on operation using the remote control.
HEADPHONE jack
Plug the headphone mini-plug into the Headphone jack
located on the front of the LCD TV set.
OPC sensor
Remote sensor
OPC indicator (Optical Picture Control)
The
Optical Picture Control indicator lights up green when the
“Backlight” is set to “Auto (OPC)”.
POWER indicator
POWER indicator lights up green when the power is on, and
red when in the standby mode (the indicator will not light
when the main power is off). The indicator lights up orange
when the wake-up timer is set.
* The examples used throughout this manual are based on
the LC-20B5M model.
To change the vertical angle of the LCD TV
set, tilt
the screen up to 5 degrees forward or
10 degrees backward. The LCD TV set can
also be rotated up to 25 degrees to right and
left. Please
adjust the angle so that the LCD
TV set can be watched most comfortably.
Card Lamp
When timer recording is set: Orange
When recording: Red
Standby: Green
PC Card Slot
Speaker
Tilt the display by grabbing onto
the carrying handle while securely
holding down the stand with your
other hand.
How to adjust the angle
Speaker
Terminals
S-VIDEO
AV-IN1
VIDEO
AUDIO (R)
AUDIO (L)
VIDEO
AUDIO (R)
AUDIO (L)
AV-IN2/OUT
Y
ANT. (Antenna terminal)
POWER INPUT (DC12V)
AUDIO (L)
AUDIO (R)
P
B
P
R
COMPONENT
Carrying handle
Rear View
How to fix the cables
• Pull the cables connected to each terminal through the holes and close the left and right terminal covers.
Push the cables into the grooves of the support covers. Insert the cable holder (supplied) from above the
support cover and fix the cables.
Terminal cover
Cable holder
Terminal cover
Support cover
LC-20B5M
5
LC-20B5M
Part Names of Remote Control
Move the cursor to the upwards
(Select the menu items)
/
Still
(Pause the motion picture playback or card recording)
Move the cursor to the right
(Select the menu items)
/
Fast Forward
(Fast forwards the picture)
Move the cursor to the downwards
(Select the menu items)
/
Stop
(stop the motion picture playback or card recording)
OK
(Set the menu or items by selecting the cursor)
/
Play
(Playback the card)
Move the cursor to the left
(Select the menu items)
/
Fast Reverse
(Fast reverses the picture)
How to use the cursor during the
motion picture playback
SUBTITLE
Displays the Teletext
Subtitle directly.
HOLD
Temporarily holds the
current Teletext page.
REC
Records the motion
picture.
(Mute)
Switches the sound on and off.
Yellow,
Timer function Menu
Cyan, Status Display
Channel Select
MENU
Displays the TV menu or return
to normal screen.
VOL (+)/(
-
)
(Flashback)
Returns to the previous
channel.
Red, Picture Menu
END
Returns to normal screen
in Teletext mode.
RETURN
Return to the previous screen.
TEXT
Displays the Teletext mode
screen.
POWER
MPX
Switches the audio
mode.
REVEAL
Displays hidden information
such as solutions to riddles
and puzzles.
CARD
Switches the motion and
still picture.
SUBPAGE
Displays the Teletext
Subpage directly.
CAPTURE
Records the still picture.
TV/VIDEO
Switches the input source
between AV1, AV2, COMPONENT,
CARD and TV mode.
BACKLIGHT
Selects the brightness and
OPC of the display.
Green, Sound Menu
CH ( )/( )
Installing Batteries in the Remote Control
Before using the LCD TV set for the first time, install the two AAA size batteries supplied in the remote control. When the
batteries become depleted and the remote control fails to operate, replace the batteries with new AAA size batteries.
1
Open the battery cover.
2
Insert two AAA size batteries.
3
Close the battery cover.
Place batteries with their
terminals corresponding to
the (+) and (–) indications in
the battery compartment.
Caution!
Precautions regarding batteries
Improper use of batteries can result in a leakage of chemicals and/or explosion. Be sure to follow the instructions below.
Place batteries with their terminals corresponding to the (+) and () indications.
Different types of batteries have different characteristics. Do not mix batteries of different types.
Do not mix old and new batteries. Mixing old and new batteries can shorten the life of new batteries and/or cause old
batteries to leak chemicals.
Remove batteries as soon as they are depleted. Chemicals that leak from batteries can cause a rash. If chemical
leakage is found, wipe it off with a cloth.
The batteries supplied with the LCD TV set may have a shorter operating time due to storage conditions.
If the remote control is not to be used for an extended period of time, remove the batteries from the remote control.
Preparation
Engaging the lower
claw with the remote
control, close the
cover.
Slide the cover while
pressing the (
) part.
+
+
6
DIMENSIONS
LC-20B5M
452 (including rubber foot)
212
384
673
403.3
39359
300.8
261
Unit: mm
6880
450 (including rubber foot)
100
178
244
100
47
7
LC-20B5M
REMOVING OF MAJOR PARTS
1. Remove the four lock screws from the stand, and detach the stand.
2. Remove the terminal covers (large and small).
3. Remove the three terminal screws.
4. Remove the fourteen lock screws from the cabinet B.
5. With the card eject button held down, open the cabinet in order of sliding it toward the PC card slot.
6. Remove the four lock screws from the stand angle, and detach the reinforcement angle.
7. Remove the wire holder and tape, and disconnect the connecting cable.
8. Disconnect all the connectors from all the PWBs.
5-4
5-3
PC Card slot
Terminal Cover (S)
4
2
Cabinet B
5-2
5-1
Cabinet A
5-1
thru
, and detach the cabinet B by
5-6
6
5-6
5
1
5-5
Reinforcement Angle
3
2
Stand
Terminal Cover (L)
Tape
7
Card LED PWB
P5003
P2005
P9001
8
SC1204
SC1201
8
CN2
Main PWB
SC1202
P2006
CN3
P2003
8
SC2001
P701
P1601
8
Analog PWB
P3302
P3303
P4050
SC3403
P3704
8
P3404
8
P4001
P3201
P3703
Operation PWB
8
P6706
P6704
8
P6703
P6702
8
P6701
P6700
8
R/C, LED PWBWire Holder Inverter PWB
7
8
LC-20B5M
9. Remove the two lock screws from the operation panel (top cover), and detach the operation panel (top cover).
10. Remove the two lock screws from the operation PWB, and detach the operation PWB.
11. Remove the lock screw from the shield, and detach the shield from the main PWB.
12. Remove the two lock screws from the R/C, LED PWB, and detach the R/C, LED PWB.
13. Remove the two lock screws each from the speaker boxes (left and right), and detach both the speaker boxes.
9
13
Speaker Box (R)
Shield
R/C, LED PWB
Operation panel (Top Cover)
Operation PWB
10
Analog PWB
13
Speaker Box (L)
Inverter PWB
12
9
LC-20B5M
14. Remove the two lock screws from the inverter PWB, and detach the inverter PWB.
15. Remo v e the fiv e loc k scre ws from the main PWB, and undo the cla ws a and b. Detach the main PWB by lifting the area around the claws and pulling the PWB out.
16. Remove the one lock screw from the card frame cover over, and detach the card frame cover.
17. Remo v e the four lock screws from the analog PWB, and undo the claws c and d. Detach the chassis fr ame (right) from the analog PWB by pulling out the terminals. In the same way, undo the claws e and f, and detach the chassis frame (left) from the analog PWB by pulling out the terminals.
Note: When detaching the main PWB and analog PWB, be careful not to break the PWB-fixing claws.
18. Remove the one lock screw from the card LED PWB, and detach the card LED PWB.
17
16
Card Frame Cover
Card LED PWB
18
15
Main PWB
a
b
c
d
Chassis Frame (R)
15
Chassis Frame (L)
e
Analog PWB
14
f
Inverter PWB
10
» Precautions in handling the liquid crystal panel
Reflection Sheet (Top) (PSHEPA103WJZZ)
Lamp Holder (Top)-B (LHLDZA212WJKZ)
Lamp Unit Ass'y (CLMP-A024WJ01)
Reflection Sheet (Bottom) (PSHEPA104WJZZ)
Lamp Holder (Bottom) (LHLDZA213WJKZ)
Back Shield (PSLDMA312WJFW)
Lamp Holder (Top)-A (LHLDZA211WJKZ)
Diffusion Sheet
(PSHEPA127WJZZ) Reflection/Defelction (PSHEPA101WJZZ)
Diffusion Plate (PCOVUA014WJZZ)
Prism Sheet (PSHEPA163WJZZ)
20" LCD Panel Unit
19
22
21
20
1. Handle it in a clean room. (above 50% humidity)
2. The worker must wear an earth band.
3. Be careful not to drop, vibrate and shock the panel.
4. Use an ionizer. (within 30 cm)
19. Remove the three lock screws from the liquid crystal panel, and detach the liquid crystal panel unit.
20. Remove the reflecting/polarizing sheet, prism sheet, diffusion sheet and diffusion plate.
21. Remove the lamp holder (top)-A, -B and the lamp holder (bottom) from the lamp unit assembly.
22. Remove the upper and lower reflection sheets from the back shield.
LC-20B5M
11
LC-20B5M
» Precautions in servicing the B side (backside) of the main PWB unit
1. Disconnect the FFC (flat cable) from between the main PWB (SC1204) and the liquid crystal panel, and then connect the service-specific extension FFC (flat cable) (QCNW-A556WJZZ).
2. Disconnect the FFC (flat cable) from between the main PWB (SC1201) and the liquid crystal panel, and then connect the service-specific extension FFC (flat cable) (QCNW-A555WJZZ).
3. Disconnect only the SC1202 of the FFC (flat cable) from between the main PWB (SC1202) and the liquid crystal panel, and then connect the service-specific extension FFC (flat cable) (QCNW-B784WJZZ).
4. Disconnect the P701 side of the lead from between the main PWB (P701) and the analog PWB, and then connect the service-specific extension cord (QCNW-C086WJQZ).
5. Disconnect the FFC from between the main PWB (SC2001) and the analog PWB (SC3403), and then connect the service-specific extension FFC (flat cable) (QCNW-A556WJZZ).
6. Disconnect the lead from between the main PWB (P2006) and the analog PWB (P1601), and then connect the service-specific extension cord (QCNW-C498WJQZ).
7. Remove the lock screws from the main PWB, detach the PWB from the chassis frame, and then turn it over to service.
» Precautions in servicing the inverter PWB unit (backside)
8. Disconnect only the P3703 side of the lead from between the inverter PWB (P6706) and the analog PWB (P3703), and then connect the service-specific extension cord (QCNW-C086WJQZ).
9. Remove the lock screws from the inverter PWB, detach the PWB (be careful not to get close to the high-tension area and its surrounding conductive parts), and then turn it over to service.
Main PWB
(Side-B)
Main PWB Inverter PWB
CN2
7
CN3
3
SC1204
SC1202
P2006
6
SC1201
1
2
SC2001
P701
45
Inverter
PWB
(Side-B)
SC3403
P3201
P3703
8
P6706
P1601
Analog PWB
Step Part No. Description
1 QCNW-A556WJZZ Extension Cable 50-pin Main (SC2004)-LCD panel 2 QCNW-A555WJZZ Extension Cable 20-pin Main (SC1201)-LCD Panel 3 QCNW-B784WJZZ Extension Cable 30-pin Main (SC1202)-LCD Panel 4 QCNW-C086WJQZ Extension Cable 10-pin Main (P701)-Analog (P3201) 5 QCNW-A556WJZZ
Extension Cable 50-pin Main (SC2001)-Analog (SC3403) 6 QCNW-C498WJQZ Extension Cable 15-pin Main (P2006)-Analog (P1601) 8 QCNW-C086WJQZ Extension Cable 10-pin Main (P6706)-Analog (P3703)
9
12
LC-20B5M
ADJUSTING PROCEDURE OF EACH SECTION
The best adjustment is made before shipping. If any position deviation is found or after part replace is performed, adjust as follows.
Preparation for Adjustments
Use the exclusive-use AC adapter or stable DC power supply.
AC adapter: UADP-A063WJPZ (LC-20B5X)
UADP-A064WJPZ (LC-20B5M)
DC power supply: 12 ± 0.5V 5.6A
1. Adjustment Procedure
1-1. Adjusting the checker
Turning on the power (initialization) Setting the model and size in inches Transferring the model-specified data to the E2PROM (I2C) Calling the adjustment process mode Starting the adjustment (+B adjustment)
1-2. Adjusting the finish process
Reassembling the set Turning on the power Calling the adjustment process mode (using the remote controller) Adjusting the counter bias, TV contrast and white balance
2. Calling the MAIN adjustment process mode
There are the following two ways to choose from.
• Set the Pin (81) (KEY4) or Pin (82) (KEY5) of IC2001 (microprocessor) to "L", turn on the power.
• For servicing, hold down the "TV/VIDEO" and "MENU" keys at once, and turn on the "POWER" switch. (Make sure the process mode "K" appears at the top left of the screen.) Then press the "CH (Ù)" and "VOL (–)" keys at once. (Make sure the adjustment process mode screen shows up.) To quit this mode, turn off the power. (Or turn off the "POWER" switch or use the remote controller’s "OFF" key.)
3. Using the keys for the adjustment process
Selecting a reception channel
• Using the "CH (ù)/(Ù)" key, turn up and down reception (broadcasting) channels. Just click on the key, and channels are selected on by one. Hold down the key, and the next receivable channel is searched up and down.
• Adjustment items Adjust each of the items by using the "MENU", "CURSOR UP/DOWN" and "VOL (+)/(–)" keys (on the set or on the remote controller).
• Select an adjustment item using the "CURSOR UP/DOWN" key.
• An adjustment item is toggled on and off by activating the MENU SELECT key (next item). Let’s suppose that the item at the bottom of a page is now selected. When the "MENU" key is activated here, the item at the top of the next page will be selected.
4. Initialization
4-1. Set pins (81) and (82) of IC2001 (microprocessor) to GND. Turn on the power. 4-2. Select the inch size (20). 4-3. Select the model number "A642M".
~Once "A642M" has been selected, the screen shuts off and the power turns off. But the power turns
itself on to get the set restarted. (The microprocessor resets itself due to a change in model number.)
13
LC-20B5M
5. Adjustment
5-1. Counter bias adjustment: COM BIAS on page 2
Adjust the "COM BIAS" setting until the contrast gets optimum (the black portion blackest). The adjustment guideline is around 100.
5-2. TAMP adjustment
1) Feed the colour bar pattern signal.
2) See if the "Y" reading on adjustment process page 2 is within the range shown below. If not, adjust the "NTSC TAMP" setting to bring the "Y" reading within the specified range.
Model LC20B5M
Adjustment value 174~189
3) If the "NTSC TAMP" setting has been readjusted, write down its new setting in the "PAL TAMP" and "SECAM TAMP" items manually.
(Page 2 of adjustment process OSD)
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26
0 1 2 3 4 5 6
7 8
9 10 11 12
13
2
COM B I AS TAMP L 71
YD TA TAMP
NTSC TAMP PAL TAMP 31 SECAM RCUTOF
GCU TOF
BCU TOF R GAIN
G GA IN
B GAIN
A
H
TAMP F F
F
1
0 1
1. 0
00
4
815 819
31
3
1
3 5 3 2
1 3
9.2
0.0 0
Y Data
(White 75%)
5-3. White balance adjustment
1) Feed the monoscope pattern signal.
2) Adjust the "RCUTOFF", "BCUTOFF", "R-GAIN" and "B-GAIN" settings on adjustment process page 3 to achieve the colour at the same level as with the standard set.
14
LC-20B5M
5-4. Other adjustments (SOUND, VPC, DPS, DAC, TUNER, OTHERS, TEXT)
1) Move the cursor to a desired item on page 4 of adjustment process menu. Press the CURSOR LEFT/ RIGHT keys, "VOL (+)/(–)" keys or OK key to select the item.
4 I2C DATA 000000000000 I2C DATA WAIT SOUND VPC DPS DAC TUNER OTHERS TEXT
2) The adjustment process menu of the item appears on the screen. The settings are now ready to change.
Screen with SOUND selected
SOUND1 VOLUME 0 AVC OFF MSP DATA 0000000000 MSP DATA WAIT 0018H ST 1D ONTA 1 CARRIER MUTE ON SP TEST OFF
3) To go back to page 4 of adjustment process menu, press the FLASHBACK key on the remote controller.
15
LC-20B5M
6. Lamp error detection
6-1. Functional description
This LCD colour television has a function (lamp error detection) to be turned off automatically for safety when the lamp or lamp circuit is abnormal. If the lamp or lamp circuit is abnormal, or some other errors happen, and the lamp error detection is executed, the followings occur. 1 The main unit of television is turned off 5 seconds after it is turned on. (The po wer LED on the front side of
TV turns from green to red.)
2 If the situation 1 happens 5 times sequentially, television can not be turned on. (The power LED remains
red.)
6-2. Countermeasures 6-2-1. Check when turning off the lamp error detection
When television is turned off by the lamp error detection mentioned above, it enters the adjustment process with the power LED red. Entering the adjustment process turns off the error detection and turns on TV. This enables the operation check to detect errors in the lamp or lamp circuit. Check whether "ERROR NO RESET" on line 4, page 1 of the adjustment process is 1 or more. If it is 1 or more, it indicates the lamp error detection was executed.
6-2-2. Resetting of the lamp error count
After confirming that the lamp or lamp circuit is normal, reset the lamp error count. Select "ERROR NO RESET" on line 4, page 1 of the adjustment process and set the number to 0 using the volume button.
Page 1 of the adjustment process
1
M O D E L A642M I N C H S I Z E 20 E R R O R N O R E S E T 5 P U B L I C M O D E OFF E X T C O N T R O OFF E X T M O D E UART U P D A T E M O D E NORMAL T E X T R E S E T OFF
V E R R O M 1. 0 0A G AI B U 0. 0 0 0
Reset 0
Afterwards, perform the operation check to confirm that the lamp error detection does not function.
16
7. Public mode
How to enter into PUBLIC MODE
1. Turn off TV by pressing MAIN POWER switch.
2. While pressing "MENU" key and "VOL(+)" key at the same time, press MAIN POWER switch for more than 2
seconds. TV will turn on, and you will see the screen display setting pass word of PUBLIC MODE. (See Figure 1)
Figure 1
3. Press "0", "2", "7" key of Remote control, you wilt see the screendisplay a setting of PUBLIC MODE.
(See Figure 2)
• Setting screen of “PUBLIC MODE”
PUBLIC MODE MAXIMUM VOLUME [ 60] VOLUME FIXED [VARIABLE] REMOTE CONTROL [RESPOND] USER CONTROL [RESPOND] MENU BUTTON [RESPOND] ON SCREEN DISPLAY [YES ] START MODE [NORMAL ] INPUT MODE FIXED [NORMAL ] SOUND ONLY MODE [NO ] RESET ENTER
1 2 ··· 59 60 VARIABLE FIXED RESPOND ↔ LIMITED ↔ NO RESPOND RESPOND NO RESPOND RESPOND NO RESPOND YES NO NORMAL AV1 COMPONENT CH1 CH2 NORMAL FIXED NO ↔ YES
CH99 CH0
...
CH98
LC-20B5M
Figure 2
Factory setting
Adjust setting
1. You can select each item of functions by pressing cursor UP/DOWN keys or CH(ù)/(Ù) Keys on the remote
control or CH(ù)/(Ù) keys on the LCD TV. The letter of selected item turns to yellow colour when you selected it.
2. The setting position of each item of functions are made by pressing cursor RIGHT/LEFT keys on the remote
control or VOL (+)/(–)keys on the LCD TV.
3. Select ENTER position after you set all functions, and press cursor RIGHT/LEFT keys on the remote control
or VOL(+)/(–)keys on the LCD TV for confirmation. Unless otherwise you make ENTER confirmation, the settings will not be memorized.
• 6-functions of Public Mode settings expand for public application
1. MAXIMUM VOLUME (1—————60)
You can set the maximum volume at your desire level.
2. VOLUME FIXED (VARIABLE / FIXED)
You can fix the sound volume at your desire level. When you set to "FIXED", the sound volume which you just set is fixed.
3. REMOTE CONTROL (RESPOND / LIMITED)
If you set "LIMITED", remote control keys of POWER, CH(ù)/(Ù), VOL(–)/(+) and BRIGHT keys are responded, but other keys are not responded. This is a position that you can not make MENU adjustments.
4. USER CONTROL (RESPOND / NO RESPOND)
"NO RESPOND" means that the TV does not respond when you press a user control buttons except main power button on the main unit.
17
LC-20B5M
5. MENU BUTTON (RESPOND / NO RESPOND) With "NO RESPOND" selected, the remote controller and the set's MENU key are disabled.
6. ON SCREEN DISPLAY (YES / NO) If you set "NO" position, OSD will not appear.
7. START MODE (NORMAL↔AV1↔COMPONENT↔CH1↔CH2 When any other item than "NORMAL" has been selected, the set gets started in the selected input mode or channel at the next switch-on.
8. INPUT MODE FIXED (NORMAL↔FIXED) (* This item cannot be selected if the start mode is "NORMAL".) If "FIXED" has been selected, any channels and input modes other than those selected in the start mode cannot be picked up.
9. SOUND ONLY MODE (NOYES) (* This item cannot be selected if "NO" appears on the on-screen display.) Let's suppose that this item has been selected and the BRIGHT key on the remote control has been pressed. The item "BRIGHTNESS [OFF]" can now be selected next to the item "BRIGHTNESS [DARK]".
Screen with "BRIGHTNESS [OFF]" selected
...
CH98CH99CH0)
Count-down started from 5
BRIGHTNESS [OFF] TURNS OFF IN 5 SECS.
Five seconds later, the screen shuts off and the sound alone is heard. Once in this mode, no picture but the OSD appears. But the channels and sound volume can still be changed.
To quit this mode, press the BRIGHT key on the remote control again and select any item other than "BRIGHTNESS [OFF]".
10. RESET You can cancel all Public Mode settings. (It returns to the factory setting.)
11. ENTER You make sure after you have specified all functions, then press the enter key. Unless otherwise you press the enter key, all positions that you have selected will not be set.
18
8. Functions of the PC card
8-1. Product outline
Sharp has adopted its original "ASV *2 method low-reflection black TFT flat panel" that can reproduce the high-contrast images with firm black ev en in bright rooms . "QS technology" *1 reduces residual images even for quick-moving subjects to realize eye-friendly images, and "I/P conversion for 3-D motions" suppresses roughness and flickering. They help you watch the high-contrast and clear images from any angles. Further more, this product is equipped with "PC card slot" to record TV programs on memory cards, and to show the still images taken with digital cameras on the large screen of an LCD TV with memory cards*. This model has new design that has side-speakers designed by Toshiyuki Kita, a world-known industrial designer. The speak ers are punching metal-processed, so they ha ve a style sho wing quality sound capabilities. The screen properties are, needless to say, much superior to CRT TV sets: lo w power consumption, long life backlight, and other power-saving features, as well as reduced flickering. * QS --> only for LC-20B5E (not available on LC-15B5E) <CARD FUNCTIONS>
(1) Enjoying recorded TV programs
To record the program you are watching, all you need is just push the record button. Supporting the hard disc PC cards newly realizes long-time recording. There are lots of recording functions*, including "Trace Recording" (Going back to record to a fe w seconds before starting recording), "Reserved Recording" (Up to 8 programs programmable a month) and "Easy Recording" (Finish time presettable during recording), and you can enjoy the recorded programs on full screen. * The video record system is MPEG-4. Smooth video with 25 frames/sec is realized. (SD memory cards, Multimedia cards, Compact flashes, Smart media, Memory sticks, xD picture cards and Micro drive are supported. For use , the PC card adapter specific for each memory card is necessary. Names of memory cards are trademark.)
EVideo Recording/Playing functions One scene in the TV program you are watching can be recorded on memory cards. The recorded video can be readily reproduced on demand. The Trace Recording function records from a few seconds before , so you need not worry about delaying the use of the remote controller. Three recording modes (SP/LP/ EP) are available for your applications.
LC-20B5M
Record mode Application Frame rate 256 MB card 5 GB card
Record time guideline
FINE 25
NORMAL
PORTABLE
Standard quality mode
Long time record mode
Portable device compatible mode
25
12.5
Approx. 10 min. Approx. 30 min.
Approx. 1 hr.
Approx. 4 hrs. Approx. 10 hrs. Approx. 25 hrs.
* Record time is variable for the TV reception condition and the video contents. * Ground-based broadcasting and external input (except for SCART RGB) that are not copy-protected can
be recorded.
* If the file capacity is over 4 GB, or the record time is longer than 12 hours , recording/pla ying is impossib le .
EStill-Picture Recording/Playing functions
1) One scene in a TV program can be recorded on memory cards as a still image.
EYou can readily record text information that you have made a memo until now.
Number of still images to be recorded
Recording size 32 MB card 128 MB card
Approx. 300
Approx. 1000
* The number of images is variable for the TV reception condition and the image contents.
2) Enjoying still images taken with digital cameras
With memory cards and on the large screen of an LCD TV, you can readily show still images captured with digital cameras*.
* Only JPEG still images that were recorded to fit the standard (Design rule for Camera File system: DCF)
by Japan Electronics and Information Technology Industries Association Corp are playable.
* The number of files displayable is up to 1,024, including video and still images.
19
LC-20B5M
8-2. PC Card Unit Spec
(1) Still-Picture Mode
1) Recording/Play File Format Based on JPEG/DCF
2) Recording Pixcel Numbers 640x480
3) Playing Pixcel numbers 640x480
(2) Motion-picture Mode
1) File system ASF
(3) Motion picture Format
SP (Fine mode) MPEG4 QVGA (320x240) 2.5Mbps 25fps LP (Normal Mode) MPEG4 QVGA (320x240) 1.0Mbps 25fps EP (Portable Mode) MPEG4 QVGA (320x240) 384Kbps 12.5fps Fitting Time Mode MPEG4 QVGA (320x240) Variable 25fps
(4) Audio Format
SP (Fine mode) WMA 2ch (Stereo) 32KHz 48Kbps LP (Normal Mode) WMA 2ch (Stereo) 32KHz 48Kbps EP (Portable Mode) G.726 1ch (monoral) 8KHz 32Kbps Fitting Time Mode WMA 2ch (Stereo) 32KHz 48Kbps
Video Codec Picel Numbers Transfer Rate Frame Rate
Video Codec No. of Channel Sampling frequency Frame Rate
(5) Maximum file size
1) 1024 file (Still & Motion)
2) 4 GB
3) 12 hour
(6) Applicable Card media
HDD Card Micro Drive Compact Flash Card Memory Stick/-DUO/-PRO SD Card/mini SD Multi media Card xD Card
Smart Media
(7) PC Card Slot Interface 68pin PCMCIA
...
Max 5 GB
...
Max 2 GB
...
Max 2 GB
...
Max 128MB/1GB
...
Max 512/32MB
...
Max 128MB
...
Max 128MB
...
Max 128MB
20
8-3. Block diagram of card unit
MSP
DC/DC
converter
IC704
4V/6V
Reg
IC5409
3.3V/5V
DA150
IC5201
Audio DSP
Data bus
5V/3.3V conversion
IC5401-IC5406
PCMCIA
Card
DM270
(IC5001)
Video DSP
DSP
1.5V
64M SDRAM
IC5006
1.5V
Reg
IC5004
DC/DC
converter
3.3V
Video decoder
(VPC) IC8801
LCD
controller
TVCPU
8 bit video, CLK, H, V (ITU-R 656)
8 bit video, CLK, H, V (ITU-R 656)
UART
4V/6V switching signal
ON/OFF
16 bit address
16 bit data
I
2
S (for recording)
I
2
S (for playing)
PC card block Main
32M FLASH
IC5003
LC-20B5M
21
LC-20B5M
PCMCIA card Used at 5V/3.3V
DM270 (IC5001) CPU, DSP, DMA C, OSD, NTSC encoder: system control, OSD display, video encoding/decoding
Used at 3.3V (1.5V for DSP)
DA150 (IC5201) Audio encoding/decoding
32M FLASH (IC5003) Storing the program for DA150 and DM270
64M SDRAM (IC5006) Used for temporary data storage and for image data compression and expansion.
Reg (IC5409) Conversing 4V/6V to 3.3V/5V for PCMCIA
Reg (IC5004) Conversing 3.3V to 1.5V for DSP in DM270
"Tips"
1) With this product, showing images recorded with PC or DSC enables you to check the playing system.
2) With PC, showing images recorded with this product enables you to check the recording system.
3) Video is played at the rate in sync with IIS CLOCK signals from audio circuit. For example, if the IIS CLOCK signals fail to reach the card playing circuit f or some reason, the video is pla y ed at the lo west r ate and is shown in slow motion.
Major input/output terminals on the card system
Card side IC (connector) Pin No. LSI terminal name Connection diagram Types of signals Explanation for signals I/O name signal name DM270 B3.3V_CARD1A B3.3V_CARD1A Power supply Power supply 3.3V for DM270 I (IC5001)
103 VIN VIN V signal from VPC to DM270 I 102 HIN HIN H signal from VPC to DM270 I 100 LLC2 (CLK) LLC2 Clock signal from VPC to DM270 I 112 YIN0 YIN0 Data signal 0 from VPC to DM270 I 111 YIN1 YIN1 Data signal 1 from VPC to DM270 I 110 YIN2 YIN2 Video input/output Data signal 2 from VPC to DM270 I 109 YIN3 YIN3 Data signal 3 from VPC to DM270 I 108 YIN4 YIN4 Data signal 4 from VPC to DM270 I 107 YIN5 YIN5 Data signal 5 from VPC to DM270 I 106 YIN6 YIN6 Data signal 6 from VPC to DM270 I 105 YIN7 YIN7 Data signal 7 from VPC to DM270 I
55 RESET RESET Data Reset signal from TV microprocessor to DM270 I 10 CA_DOUT DOUT communication Data signal from TV microprocessor to DM270 I 11 DIN DIN Data signal from DM270 to TV microprocessor I 70 VOUT VOUT V signal from DM270 to IP O 69 HOUT HOUT H signal from DM270 to IP O 68 CKOUT CKOUT Clock signal from DM270 to IP O 81 YOUT0 YOUT0 Data signal 0 from DM270 to IP O 77 YOUT1 YOUT1 Data signal 1 from DM270 to IP O 76 YOUT2 YOUT2 Video input/output Data signal 2 from DM270 to IP O 75 YOUT3 YOUT3 Data signal 3 from DM270 to IP O 74 YOUT4 YOUT4 Data signal 4 from DM270 to IP O 73 YOUT5 YOUT5 Data signal 5 from DM270 to IP O 72 YOUT6 YOUT6 Data signal 6 from DM270 to IP O 71 YOUT7 YOUT7 Data signal 7 from DM270 to IP O
P5003 1 I2S_WS S_WS I2S word strobe L: Right audio input / H: Left audio input I
2 GND 3 I2S_CL S_CL Clock for I2S serial data transmission timing I 4 GND 5 I2SDA_OUT S_DO Audio input/output Audio data input from TV main unit I 6 GND 7 I2SDA_IN1 S_DI In card mode: Card Audio / Not in card mode: Shutter sound O 8 GND 9 I2SDA_IN2 SH_DI
10 GND
Reg 1 IN B4V/6V1_1A 4V/6V output from DC/DC converter to Reg O (IC5409) 2 SW B4V/6V1_1A ON/OFF switch I
3 OUT V5EN Power supply 3V power input from DC/DC converter to Reg I
V3EN 5V power input from DC/DC converter to Reg I 4 ADJ For adjustment 5 GND GND GND
22
LC-20B5M
Main Side IC (connector) Pin No. Terminal name Signal name Types of signals Explanation for signals I/O name P701 9 3.3V (SUB) B3.3V2A Power supply Power supply 3.3V for DM270 (NA215WJ)
VPC 57 VS VPC_VS V signal from VPC to DM270 O (Video decoder) 56 MSY/HS VPC_HS H signal from VPC to DM270 O IC8801 27 LLC2 LLC2 Clock signal from VPC to DM270 O
40 Y0 VPC_YIN0 Data signal 0 from VPC to DM270 O 39 Y1 VPC_YIN1 Data signal 1 from VPC to DM270 O 38 Y2 VPC_YIN2 Video input/output Data signal 2 from VPC to DM270 O 37 Y3 VPC_YIN3 Data signal 3 from VPC to DM270 O 34 Y4 VPC_YIN4 Data signal 4 from VPC to DM270 O 33 Y5 VPC_YIN5 Data signal 5 from VPC to DM270 O 32 Y6 VPC_YIN6 Data signal 6 from VPC to DM270 O 31 Y7 VPC_YIN7 Data signal 7 from VPC to DM270 O
TV 83 CARDRST RESET microprocessor 35 SUB_DOUT DOUT Rese (IC2201) 36 SUB_DIN DIN Data signal from DM270 to TV microprocessor I I/P conversion 207 VS_P2 VD_VS V signal from DM270 to IP I IC 208 HS_P2 VD_HS H signal from DM270 to IP I
195 IN_CLK_P2 VD_CKO Clock signal from DM270 to IP I 196 P2_0 VPC_0 Data signal 0 from DM270 to IP I 199 P2_1 VPC_1 Data signal 1 from DM270 to IP I 200 P2_2 VPC_2 Video input/output Data signal 2 from DM270 to IP I 201 P2_3 VPC_3 Data signal 3 from DM270 to IP I 202 P2_4 VPC_4 Data signal 4 from DM270 to IP I 203 P2_5 VPC_5 Data signal 5 from DM270 to IP I 204 P2_6 VPC_6 Data signal 6 from DM270 to IP I 205 P2_7 VPC_7 Data signal 7 from DM270 to IP I
MSP 5 I2S_WS S_WS I2S word strobe L: Right audio input / H: Left audio input O (
Audio processor
DC/DC converter B4V/6V1_1A B4V/6V1_1A Power supply 4V/6V output from DC/DC converter to Reg O IC704
)
4 I2S_CL S_CL Clock for I2S serial data transmission timing O
6 I2SDA_OUT S_DO Audio input/output Audio data input from TV main unit O
7 I2SDA_IN1 S_DI In card mode: Card Audio / Not in card mode: Shutter sound I
Data communication,
t
Reset signal from TV microprocessor to DM270 O Data signal from TV microprocessor to DM270 O
Abolished
23
LC-20B5M
No picture and sound
Check all the settings on the microprocessor'fs adjust process menu.
Fluorescent light in trouble
Are F3701 and F3702 normal?
YES
YES
YES
YES
YES
YES
NO
NO
NO
NO
NO
NO
YES
YES
NO
Does the load side keep
normal circuits when F3701
and F3702 are disconnected?
Are F3701, F3702, F6700,
F6701, F6702, F6703 and
F6704 normal?
Do Q6702, Q6705, Q6708,
Q6711 and Q6714 keep
normal circuits?
Check Q6702, Q6705, Q6708,
Q6711, Q6714 and their
peripheral circuits.
Check S4053 and the
connecting cables.
Check the connecting cables
and the peripheral circuits of
J3701.
Are pins (10) and (11) of
IC1201"H"?
Are the oscillation waves from
the primary sides of T6700
thru T6709 normal?
Check and replace the
fluorescent light.
Check the connecting cables
and the peripheral circuits of
Q6700 thru Q6713.
Check that line, IC1201 and
their peripheral circuits.
Are +34V, +9V and +5V on the
secondary side output at T701
normal?
Are +35V, +9V and +5V on
the secondary side output at
T701 normal?
Are pins (14) of IC702 thru
IC707 normal? (1.35V-2.05V)
Check the load side.
Do Q716, S4053 and the
peripheral circuits on the
primary side of T3701 keep
normal circuits?
Replace F3701 and F3702.
TROUBLE SHOOTING TABLE
24
No picture (1/2)
No picture at all
No TV , VIDEO 1, VIDEO 2
and VIDEO 3 outputs
No TV output
No VIDEO 1 output
No VIDEO 2 output
Check all the settings on the microprocessor'fs adjust process menu.
NO
NO
NO NO NO NO
NO
NO
NO
NO
NO
NO
YES YES
YES
YES YES
No S-VIDEO output
No COMPONENT output
YES
YES
YES
YES
No picture (2/2)
No PC card output
Check all the settings on the microprocessorÅfs adjust process menu.
NO
NO
NO
NO
YES
YES
YES
YES
Are the
input/output
at IC8801
normal?
Are the
input/output
at IC3401
normal?
Check
IC3401 and
its peripheral
circuits.
Check the
power supply
line.
Is the input
at pin (1) of
IC3401
normal?
Is the input
at pin (8) of
IC3401
normal?
Is the input at pins
(71) and (72) of
IC8801 normal?
Is the input at pins (4), (5),
(6) and (75) of IC8801
normal? (D1)
Is the input at pins (43),
(48) and (54) of IC8701
normal? (D2)
Check the DVD_Y, CB and
CR lines of J2205 and their
peripheral circuits.
Check the SY and SC
lines of J3401 and
their peripheral
circuits.
Is the output
at IC3401
normal?
Is the output
at IC3401
normal?
Check
IC3401 and
its peripheral
circuits.
Check
IC3401 and
its peripheral
circuits.
Check that
line.
Check that
line.
Is the voltage
at pins (6),
(7) and (9) of
the tuner
normal?
Is the output
at pin (19) of
the tuner
normal?
Is the input
at pin (47) of
IC3401
normal?
Is the output
at IC3401
normal?
Check that
line.
Check
IC3401 and
its peripheral
circuits.
Are the card
medium and its files
normal?
Check the
medium and
its files.
Is the output at
IC8602 and IC8603
normal?
Check that
line.
Replace the card
unit.
Is the voltage at
pins (2) and (3) of
P5001 in the PC
card unit normal?
Check the
power supply
line.
Is the voltage at
pins (1), (2) and (3)
of IC5004 and at
pins (1), (2) and (3)
of IC5005 normal?
Check the
power supply
line.
Check the
tuner and its
peripheral
circuits.
Check that
line.
Is the input
at pin (73)
of IC8801
normal?
Check the
AV1 line of
IC8801 and
its peripheral
circuits.
Are the
input/output
at IC1201
normal?
Check the voltage and
waves at the liquid
crystal panel.
Check
IC1201 and
its peripheral
circuits.
Check
IC8801 and
its peripheral
circuits.
Are inputs
and outputs
of Q1602,
Q1604 and
Q1606 as
specified?
Check
Q1602,
Q1604,
Q1606 and
its
peripheral
parts.
Is output at
pins
(57)~(59) of
IC1601
normal?
Check the
R, G and B
line.
Is input at
pin (21) of
IC1601
normal?
Check V2V0
line and its
peripheral
parts.
Check
IC1601 and
its
peripheral
parts.
No TELE TEXToutput
No
Yes
Yes
No
No
Yes
TROUBLE SHOOTING TABLE (Continued)
LC-20B5M
25
LC-20B5M
No sound
No sound from speakers
YES
YES
YES
YES
YES
YES
NO
YES
YES
YES
YES
NO
NO
NO
NO
NO
NO
NO
NO
NO
Check the following.
1 No audio output from TV ... Check the
peripheral circuits of Q3202 and TU3000.
2 No audio output from VIDEO 1 input ...
Check J3402 thru pins (2) and (4) of
IC3401.
3 No audio output from VIDEO 2 input ...
Check J3409 thru pins (22) and (24) of
IC3401.
4 No audio output from VIDEO 3 input ...
Check J3403 thru pins (9) and (11) of
IC3401.
5 No audio output from COMPONENT input ...
Check J3406 and J3404 thru pins (46) and
(48) of IC3401.
Is there the audio output in any input mode (TV, VIDEO 1/2
and COMPONENT)?
Check the following.
1
Is the monitor output setting at "Audio fixed"?
2
Is the sound volume loud enough?
3
Is the mute mode released?
4
Are the headphones unplugged?
Is the power supply voltage at each circuit normal?
Pin (8) of IC3301 and pin (39) of IC3201 Approx. +8V
Pins (11), (12), (13), (65) and (66) of IC3201 Approx. +5V
No sound from monitor output
Is there the audio signal output at pins (33)(Rch) and
(34)(Lch) of IC3201?
Is pin (58) of IC2001 "H"?
Is the signal from the Q2203 collector "L"?
Check pins (33)(Rch) and (34)(Lch) of IC3201 thru pins
(4)(Lch) and (2)(Rch) of J3404.
Check the following.
1
Is there the audio output from speakers?
2
Is the monitor output connected correctly?
3
Is the mute mode released?
Check the following.
1
Go to "No Audio from Speakers"h.
2
Connect the monitor output correctly.
3
Release the mute mode.
Check the peripheral circuits of IC3201.
Check pin (4) of J4021 thru pin (58) of
IC2001.
Check pin (55) of IC2001 thru Q2203, and
Q2201.
Is there the control signal input at each pin of IC3201?
Pin (2) of IC3201 SCL1
Pin (3) of IC3201 SDA1
Are the oscillation waves from pins (71) and (72) of IC3201
normal?
Check pins (29) and (30) of IC2001 thru pins (2)
and (3) of IC3201.
Check the peripheral circuits of X3201.
Is there the audio signal output at pins (27)(Rch) and
(28)(Lch) of IC3201?
Check pins (27)(Rch) and (28)(Lch) of IC3201 thru pins
(7)(Rch) and (1)(Lch) of IC3301, and the peripheral circuits
of IC3301 and IC3303.
Check the peripheral circuits of IC3201.
Recheck the following.
1
Set the monitor output to "Audio fixed".
2
Increase the sound volume.
3
Release the mute mode.
4
Unplug the headphones.
Check the following.
+8V system ... Check the peripheral circuits of
Q3711 thru pin (8) of IC3301 and
pin (39) of IC3201.
+5V system ... Check the T701 output B5V500MA
line thru each +5V input pin of
IC3201.
TROUBLE SHOOTING TABLE (Continued)
26
TROUBLE SHOOTING TABLE (Continued)
No Colours
No TV colours No VIDEO colours
No S-VIDEO colours
No COMPONENT colours
Check all the settings on the microprocessor's adjust process menu.
YES
NO
NO
Is the input at pin (71) of
IC8801 normal?
Is the input at pins (4) and
(6) of IC8801 normal? (D1)
Is the input at pins (43) and
(54) of IC8701 normal?
(D2)
Check the CB and CR
lines of J2205 and their
peripheral circuits.
Check the output at
IC8801 (D1), output at
IC8701 (D2), input/output
at IC1201 and their
peripheral circuits.
Check the SC line of J2201
and its peripheral circuits.
LC-20B5M
27
LC-20B5M
CHASSIS LAYOUT
H
G
F
OPERATION Unit
ANALOG UnitMain Unit
INVERTER Unit
E
D
C
B
CARD LED Unit
R/C, LED Unit
A
121110987654321
28
29
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