Sylvania LC420SS8 Schematic

SERVICE MANUAL
42 COLOR LCD TELEVISION
LC420SS8
IMPORTANT SAFETY NOTICE
Proper service and repair is important to the safe, reliable operation of all Funai Equipment. The service procedures recommended by Funai and described in this service manual are effective methods of performing service operations. Some of these service special tools should be used when and as recommended.
It is important to note that this service manual contains various CAUTIONS and NOTICES which should be carefully read in order to minimize the risk of personal injury to service personnel. The possibility exists that improper service methods may damage the equipment. It also is important to understand that these CAUTIONS and NOTICES ARE NOT EXHAUSTIVE. Funai could not possibly know, evaluate and advice the service trade of all conceivable ways in which service might be done or of the possible hazardous consequences of each way. Consequently, Funai has not undertaken any such broad evaluation. Accordingly, a servicer who uses a service procedure or tool which is not recommended by Funai must first use all precautions thoroughly so that neither his safety nor the safe operation of the equipment will be jeopardized by the service method selected.
TABLE OF CONTENTS
Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-1
Important Safety Precautions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-1
Standard Notes for Servicing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-1
Cabinet Disassembly Instructions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-1
Electrical Adjustment Instructions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-1
How to initialize the LCD Television . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-1
Block Diagrams . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-1
Schematic Diagrams / CBA’s and Test Points. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-1
Waveforms . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-1
Wiring Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10-1
Exploded Views. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11-1
Mechanical Parts List . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12-1
Electrical Parts List . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13-1
The LCD panel is manufactured to provide many years of useful life. Occasionally a few non active pixels may appear as a tiny spec of color. This is not to be considered a defect in the LCD screen.

SPECIFICATIONS

< TUNER / NTSC >
ANT. Input ---------------------- 75 ohm Unbal., F type
Description Condition Unit Nominal Limit
1. AFT Pull-In Range --- MHz ±2.3 ±2.1 20
20 23
2. Syncronizing Sens.
TV.ch.4 CA.ch.31 CA.ch.87
dBµ dBµ dBµ
---
---
---
< TUNER / ATSC >
Description Condition Unit Nominal Limit
1. Received Freq. Range (-28dBm) --- kHz --- ±100
2. ATSC Dynamic Range (min / max)
ch.4 ch.10 ch.41
dBm dBm dBm
---
---
---
-76/+6
-76/+6
-76/+6
< LCD PANEL >
Description Condition Unit Nominal Limit
1. Native Pixel Resolusion
2. Brightness (w / filter) --- cd/m
3. Viewing Angle
Horizontal
Vert ical
Horizontal
Vert ical
pixels pixels
° °
1920 1080
2
500 ---
---
---
---
---
-89 to +89
-89 to +89
< VIDEO >
Description Condition Unit Nominal Limit
1. Over Scan
2. Color Temperature
3. Resolution (composite video)
Horizontal
Vert ical
--­x y
Horizontal
Vert ical
% %
°K 12000
line line
5±5 5±5
0.272
0.278 720
480
---
---
--­±10% ±10%
---
---
1-1 A81H1SP
< AUDIO >
All items are measured across 8 load at speaker output terminal with L.P.F. / Video1 Input.
Description Condition Unit Nominal Limit
1. Audio Output Power 10% THD: Lch/Rch W 10.0/10.0 9.0/9.0
2. Audio Distortion 500mW: Lch/Rch % 0.5/0.5 2.0/2.0
-
3. Audio Freq. Response (NTSC)
Note: Nominal specifications represent the design specifications. All units should be able to approximate these.
Some will exceed and some may drop slightly below these specifications. Limit specifications represent the absolute worst condition that still might be considered acceptable. In no case should a unit fail to meet limit specifications.
6dB: Lch
-
6dB: Rch
Hz Hz
20 to 10 k 20 to 10 k
---
---
1-2 A81H1SP

IMPORTANT SAFETY PRECAUTIONS

Prior to shipment from the factory, our products are strictly inspected for recognized product safety and electrical codes of the countries in which they are to be sold. However, in order to maintain such compliance, it is equally important to implement the following precautions when a set is being serviced.
Safety Precautions for LCD TV Circuit
1. Before returning an instrument to the
customer, always make a safety check of the
entire instrument, including, but not limited to, the following items:
a. Be sure that no built-in protective devices are
defective and have been defeated during servicing. (1) Protective shields are provided on this chassis to protect both the technician and the customer. Correctly replace all missing protective shields, including any removed for servicing convenience. (2) When reinstalling the chassis and/or other assembly in the cabinet, be sure to put back in place all protective devices, including but not limited to, nonmetallic control knobs, insulating fishpapers, adjustment and compartment covers/shields, and isolation resistor/capacitor networks. Do not operate this instrument or
permit it to be operated without all protective devices correctly installed and functioning. Servicers who defeat safety features or fail to perform safety checks may be liable for any resulting damage.
b. Be sure that there are no cabinet openings
through which an adult or child might be able to insert their fingers and contact a hazardous voltage. Such openings include, but are not limited to, (1) spacing between the Liquid Crystal Panel and the cabinet mask, (2) excessively wide cabinet ventilation slots, and (3) an improperly fitted and/or incorrectly secured cabinet back cover.
c. Antenna Cold Check - With the instrument AC
plug removed from any AC source, connect an electrical jumper across the two AC plug prongs. Place the instrument AC switch in the on position. Connect one lead of an ohmmeter to the AC plug prongs tied together and touch the other ohmmeter lead in turn to each tuner antenna input exposed terminal screw and, if applicable, to the coaxial connector. If the measured resistance is less than 1.0 megohm or greater than 5.2 megohm, an abnormality exists that must be corrected before the instrument is returned to the customer. Repeat this test with the instrument AC switch in the off position.
d. Leakage Current Hot Check - With the
instrument completely reassembled, plug the AC line cord directly into a 120 V AC outlet. (Do not use an isolation transformer during this test.) Use a leakage current tester or a metering system that complies with American National Standards Institute (ANSI) C101.1 Leakage Current for Appliances and Underwriters Laboratories (UL) 1410, (50.7). With the instrument AC switch first in the on position and then in the off position, measure from a known earth ground (metal water pipe, conduit, etc.) to all exposed metal parts of the instrument (antennas, handle brackets, metal cabinet, screw heads, metallic overlays, control shafts, etc.), especially any exposed metal parts that offer an electrical return path to the chassis. Any current measured must not exceed 0.5 milli-ampere. Reverse the instrument power cord plug in the outlet and repeat the test.
READING SHOULD NOT BE ABOVE 0.5 mA
LEAKAGE
DEVICE
BEING
TESTED
TEST ALL EXPOSED METAL SURFACES
ALSO TEST WITH PLUG REVERSED USING AC ADAPTER PLUG AS REQUIRED
ANY MEASUREMENTS NOT WITHIN THE LIMITS SPECIFIED HEREIN INDICATE A POTENTIAL SHOCK HAZARD THAT MUST BE ELIMINATED BEFORE RETURNING THE INSTRUMENT TO THE CUSTOMER OR BEFORE CONNECTING THE ANTENNA OR ACCESSORIES.
2. Read and comply with all caution and safety-
related notes on or inside the receiver cabinet, on the receiver chassis, or on the Liquid Crystal Panel.
CURRENT
TESTER
+
EARTH GROUND
_
2-1 LTVN_ISP
3. Design Alteration Warning - Do not alter or add to the mechanical or electrical design of this TV receiver. Design alterations and additions, including, but not limited to circuit modifications and the addition of items such as auxiliary audio and/or video output connections, might alter the safety characteristics of this receiver and create a hazard to the user. Any design alterations or additions will void the manufacturer's warranty and may make you, the servicer, responsible for personal injury or property damage resulting therefrom.
4. Hot Chassis Warning ­a. Some TV receiver chassis are electrically
connected directly to one conductor of the AC power cord and maybe safety-serviced without an isolation transformer only if the AC power plug is inserted so that the chassis is connected to the ground side of the AC power source. To confirm that the AC power plug is inserted correctly, with an AC voltmeter, measure between the chassis and a known earth ground. If a voltage reading in excess of
1.0 V is obtained, remove and reinsert the AC power plug in the opposite polarity and again measure the voltage potential between the chassis and a known earth ground.
b. Some TV receiver chassis normally have 85V
AC(RMS) between chassis and earth ground regardless of the AC plug polarity. This chassis can be safety-serviced only with an isolation transformer inserted in the power line between the receiver and the AC power source, for both personnel and test equipment protection.
c. Some TV receiver chassis have a secondary
ground system in addition to the main chassis ground. This secondary ground system is not isolated from the AC power line. The two ground systems are electrically separated by insulation material that must not be defeated or altered.
5. Observe original lead dress. Take extra care to assure correct lead dress in the following areas: a. near sharp edges, b. near thermally hot parts-be sure that leads and components do not touch thermally hot parts, c. the AC supply, d. high voltage, and, e. antenna wiring. Always inspect in all areas for pinched, out of place, or frayed wiring. Check AC power cord for damage.
6. Components, parts, and/or wiring that appear to have overheated or are otherwise damaged should be replaced with components, parts, or wiring that meet original specifications. Additionally, determine the cause of overheating and/or damage and, if necessary, take corrective action to remove any potential safety hazard.
7. Product Safety Notice - Some electrical and mechanical parts have special safety-related characteristics which are often not evident from visual inspection, nor can the protection they give necessarily be obtained by replacing them with components rated for higher voltage, wattage, etc. Parts that have special safety characteristics are identified by a # on schematics and in parts lists. Use of a substitute replacement that does not have the same safety characteristics as the recommended replacement part might create shock, fire, and/or other hazards. The product's safety is under review continuously and new instructions are issued whenever appropriate. Prior to shipment from the factory, our products are strictly inspected to confirm they comply with the recognized product safety and electrical codes of the countries in which they are to be sold. However, in order to maintain such compliance, it is equally important to implement the following precautions when a set is being serviced.
2-2 LTVN_ISP
Precautions during Servicing
A. Parts identified by the # symbol are critical for
safety. Replace only with part number specified.
B. In addition to safety, other parts and assemblies
are specified for conformance with regulations applying to spurious radiation. These must also be replaced only with specified replacements. Examples: RF converters, RF cables, noise blocking capacitors, and noise blocking filters, etc.
C. Use specified internal wiring. Note especially:
1) Wires covered with PVC tubing
2) Double insulated wires
3) High voltage leads
D. Use specified insulating materials for hazardous
live parts. Note especially:
1) Insulation Tape
2) PVC tubing
3) Spacers
4) Insulators for transistors.
E. When replacing AC primary side components
(transformers, power cord, etc.), wrap ends of wires securely about the terminals before soldering.
F. Observe that the wires do not contact heat
producing parts (heat sinks, oxide metal film resistors, fusible resistors, etc.)
G. Check that replaced wires do not contact sharp
edged or pointed parts.
H. When a power cord has been replaced, check that
5~6 kg of force in any direction will not loosen it.
I. Also check areas surrounding repaired locations. J. Use care that foreign objects (screws, solder
droplets, etc.) do not remain inside the set.
K. When connecting or disconnecting the internal
connectors, first, disconnect the AC plug from the AC supply outlet.
L. When installing parts or assembling the cabinet
parts, be sure to use the proper screws and tighten certainly.
2-3 LTVN_ISP
Safety Check after Servicing
Examine the area surrounding the repaired location for damage or deterioration. Observe that screws, parts and wires have been returned to original positions. Afterwards, perform the following tests and confirm the specified values in order to verify compliance with safety standards.
1. Clearance Distance
When replacing primary circuit components, confirm specified clearance distance (d) and (d') between soldered terminals, and between terminals and surrounding metallic parts. (See Fig. 1)
Table 1: Ratings for selected area
Chassis or Secondary Conductor
Primary Circuit
AC Line Voltage Region
110 to 130 V
Note: This table is unofficial and for reference only. Be
sure to confirm the precise values.
U.S.A. or
Canada
Clearance
Distance (d), (d’)
3.2 mm
(0.126 inches)
2. Leakage Current Test
Confirm the specified (or lower) leakage current between B (earth ground, power cord plug prongs) and externally exposed accessible parts (RF terminals, antenna terminals, video and audio input and output terminals, microphone jacks, earphone jacks, etc.) is lower than or equal to the specified value in the table below.
Measuring Method: (Power ON)
Insert load Z between B (earth ground, power cord plug prongs) and exposed accessible parts. Use an AC voltmeter to measure across both terminals of load Z. See Fig. 2 and following table.
d' d
Fig. 1
Exposed Accessible Part
Z
AC Voltmeter (High Impedance)
Earth Ground
B
Power Cord Plug Prongs
Fig. 2
Table 2: Leakage current ratings for selected areas
AC Line Voltage Region Load Z Leakage Current (i) Earth Ground (B) to:
110 to 130 V
Note: This table is unofficial and for reference only. Be sure to confirm the precise values.
U.S.A. or
Canada
0.15 µF CAP. & 1.5 k
RES. Connected in parallel
2-4 LTVN_ISP
i 0.5 mA rms
Exposed accessible
parts

STANDARD NOTES FOR SERVICING

Circuit Board Indications
1. The output pin of the 3 pin Regulator ICs is indicated as shown.
Top View
Out
2. For other ICs, pin 1 and every fifth pin are indicated as shown.
Pin 1
3. The 1st pin of every male connector is indicated as shown.
Pin 1
Input
In
Bottom View
5
10
Pb (Lead) Free Solder
Pb free mark will be found on PCBs which use Pb free solder. (Refer to figure.) For PCBs with Pb free mark, be sure to use Pb free solder. For PCBs without Pb free mark, use standard solder.
Pb free mark
How to Remove / Install Flat Pack-IC
1. Removal
With Hot-Air Flat Pack-IC Desoldering Machine:
1. Prepare the hot-air flat pack-IC desoldering machine, then apply hot air to the Flat Pack-IC (about 5 to 6 seconds). (Fig. S-1-1)
Fig. S-1-1
2. Remove the flat pack-IC with tweezers while applying the hot air.
3. Bottom of the flat pack-IC is fixed with glue to the CBA; when removing entire flat pack-IC, first apply soldering iron to center of the flat pack-IC and heat up. Then remove (glue will be melted). (Fig. S-1-6)
4. Release the flat pack-IC from the CBA using tweezers. (Fig. S-1-6)
CAUTION:
1. The Flat Pack-IC shape may differ by models. Use an appropriate hot-air flat pack-IC desoldering machine, whose shape matches that of the Flat Pack-IC.
2. Do not supply hot air to the chip parts around the flat pack-IC for over 6 seconds because damage to the chip parts may occur. Put masking tape around the flat pack-IC to protect other parts from damage. (Fig. S-1-2)
3-1 TVN_SN
3. The flat pack-IC on the CBA is affixed with glue, so be careful not to break or damage the foil of each pin or the solder lands under the IC when removing it.
With Soldering Iron:
1. Using desoldering braid, remove the solder from all pins of the flat pack-IC. When you use solder flux which is applied to all pins of the flat pack-IC, you can remove it easily. (Fig. S-1-3)
CBA
Masking Tape
Tweezers
Hot-air Flat Pack-IC Desoldering Machine
Flat Pack-IC
Fig. S-1-2
Flat Pack-IC
Desoldering Braid
Soldering Iron
Fig. S-1-3
2. Lift each lead of the flat pack-IC upward one by one, using a sharp pin or wire to which solder will not adhere (iron wire). When heating the pins, use a fine tip soldering iron or a hot air desoldering machine. (Fig. S-1-4)
Sharp Pin
Fine Tip Soldering Iron
3. Bottom of the flat pack-IC is fixed with glue to the CBA; when removing entire flat pack-IC, first apply soldering iron to center of the flat pack-IC and heat up. Then remove (glue will be melted). (Fig. S-1-6)
4. Release the flat pack-IC from the CBA using tweezers. (Fig. S-1-6)
Fig. S-1-4
3-2 TVN_SN
With Iron Wire:
1. Using desoldering braid, remove the solder from all pins of the flat pack-IC. When you use solder flux which is applied to all pins of the flat pack-IC, you can remove it easily. (Fig. S-1-3)
2. Affix the wire to a workbench or solid mounting point, as shown in Fig. S-1-5.
3. While heating the pins using a fine tip soldering iron or hot air blower, pull up the wire as the solder melts so as to lift the IC leads from the CBA contact pads as shown in Fig. S-1-5.
4. Bottom of the flat pack-IC is fixed with glue to the CBA; when removing entire flat pack-IC, first apply soldering iron to center of the flat pack-IC and heat up. Then remove (glue will be melted). (Fig. S-1-6)
5. Release the flat pack-IC from the CBA using tweezers. (Fig. S-1-6)
Note: When using a soldering iron, care must be
taken to ensure that the flat pack-IC is not being held by glue. When the flat pack-IC is removed from the CBA, handle it gently because it may be damaged if force is applied.
Hot Air Blower
2. Installation
1. Using desoldering braid, remove the solder from the foil of each pin of the flat pack-IC on the CBA so you can install a replacement flat pack-IC more easily.
2. The “” mark on the flat pack-IC indicates pin 1. (See Fig. S-1-7.) Be sure this mark matches the 1 on the PCB when positioning for installation. Then presolder the four corners of the flat pack-IC. (See Fig. S-1-8.)
3. Solder all pins of the flat pack-IC. Be sure that none of the pins have solder bridges.
Example :
Pin 1 of the Flat Pack-IC is indicated by a " " mark.
Fig. S-1-7
To Solid Mounting Point
CBA
Tweezers
Iron Wire
Soldering Iron
Fig. S-1-5
Fine Tip Soldering Iron
Flat Pack-IC
or
Presolder
Flat Pack-IC
CBA
Fig. S-1-8
Fig. S-1-6
3-3 TVN_SN
Instructions for Handling Semi­conductors
Electrostatic breakdown of the semi-conductors may occur due to a potential difference caused by electrostatic charge during unpacking or repair work.
1. Ground for Human Body
Be sure to wear a grounding band (1 M) that is properly grounded to remove any static electricity that may be charged on the body.
2. Ground for Workbench
Be sure to place a conductive sheet or copper plate with proper grounding (1 M) on the workbench or other surface, where the semi-conductors are to be placed. Because the static electricity charge on clothing will not escape through the body grounding band, be careful to avoid contacting semi-conductors with your clothing.
<Incorrect>
<Correct>
1M
CBA
Grounding Band
1M
CBA
Conductive Sheet or Copper Plate
3-4 TVN_SN

CABINET DISASSEMBLY INSTRUCTIONS

1. Disassembly Flowchart
This flowchart indicates the disassembly steps for the cabinet parts, and the CBA in order to gain access to item(s) to be serviced. When reassembling, follow the steps in reverse order. Bend, route and dress the cables as they were.
[1] Stand Base
[8] Jack CBA
[18] Speaker(s)
[5] Jack Holder(D)
[6] Shield Box
[7] Digital Main CBA Unit
[2] Stand Cover
[3] Rear Cabinet
[9] Power Supply CBA
[10] PCB Holder
[11] Stand Shaft (L,R)
[12] Chassis
Bracket (L,R)
[13] LCD Module Assembly
[19] Front Cabinet
[14] Function CBA
[17] Side Jack CBA
[4] Inverter Power CBA
[15] Junction CBA
[16] IR Sensor CBA
2. Disassembly Method
Removal
Step/
Loc.
Part
No.
[1] Stand Base D1 4(S-1), 4(S-2) ---
Stand
[2]
Cover Rear
[3]
Cabinet
Inverter
[4]
Power CBAD2D5
Jack
[5]
Holder(D)
[6] Shield Box D2 5(S-10), 2(S-11), (N-1) ---
Digital Main
[7]
CBA UnitD2D5
[8] Jack CBA
Remove/*Unhook/
Fig.
No.
Unlock/Release/
Unplug/Unclamp/
Note
Desolder
D1 --------------- ---
D1 6(S-3), 2(S-4), 11(S-5) ---
5(S-6), *CN701, *CN702, *CN751, *CN752, *CN753
D2 (S-7), 2(S-8), 2(S-9) ---
*CN200, *CN201, *CN202, *CN203, *CN3707, *CN4201
D3D55(S-12), *CL7002A,
*CN7002
---
---
---
Removal
Step/
Loc.
No.
Part
Remove/*Unhook/
Fig.
No.
Unlock/Release/
Unplug/Unclamp/
Note
Desolder
[9]
Power Supply CBA
D3D58(S-13), *CN204,
*CN801, *CN802
---
[10] PCB Holder D3 4(S-14) ---
Stand Shaft
[11]
(L, R)
D4 4(S-15) ---
Chassis
[12]
Bracket
D4 6(S-16) ---
(L, R) LCD
[13]
Module
D4 13(S-17) ---
Assembly
[14]
[15]
[16]
[17]
Function CBA
Junction CBA
IR Sensor CBA
Side Jack CBA
D4
3(S-18), *CL106B ---
D5 D4
*CL101A ---
D5 D4
2(S-19) ---
D5 D4
2(S-20) ---
D5
[18] Speaker(s) D4 8(S-21) ---
Front
[19]
(1)
Cabinet
(2)
D4 --------------- ---
(3)
(4)
(5)
Note:
(1) Order of steps in procedure. When reassembling,
follow the steps in reverse order. These numbers are also used as the Identification (location) No. of parts in figures.
(2) Parts to be removed or installed. (3) Fig. No. showing procedure of part location (4) Identification of parts to be removed, unhooked,
unlocked, released, unplugged, unclamped, or desoldered. N = Nut, L = Locking Tab, S = Screw, CN = Connector * = Unhook, Unlock, Release, Unplug, or Desolder e.g. 2(S-2) = two Screws (S-2), 2(L-2) = two Locking Tabs (L-2)
(5) Refer to the following "Reference Notes in the
Table."
4-1 A81H1DC
(S-5)
(S-5)
(S-3)
(S-4)
(S-3)
[3] Rear Cabinet
[2] Stand Cover
(S-5)
(S-5)
(S-5)
(S-2)
(S-1)
(S-4)
(S-5)
(S-3)
(S-5)
(S-3)
(S-1)
(S-2)
[1] Stand Base
Fig. D1
4-2 A81H1DC
(S-6)
[4] Inverter Power CBA
[7] Digital Main CBA Unit
(S-6)
(S-11)
(N-1)
(S-8)
(S-7)
(S-10)
(S-9)
[6] Shield Box
[5] Jack Holder(D)
Fig. D2
4-3 A81H1DC
(S-14)
(S-14)
[10] PCB Holder
[8] Jack CBA
(S-14)
(S-12)
(S-13)
(S-14)
(S-13)
[9] Power Supply CBA
(S-13)
Fig. D3
4-4 A81H1DC
[19] Front Cabinet
[17] Side Jack CBA
[13] LCD Module Assembly
(S-20)
[16] IR Sensor CBA
[18] Speaker
(S-17)
(S-19)
(S-17)
(S-21)
[15] Junction CBA
(S-18)
[14] Function CBA
[18] Speaker
(S-17)
(S-17)(S-17)
(S-21)
(S-17)
(S-17)
(S-17)
(S-16)
[12] Chassis Bracket (L)
[12] Chassis Bracket (R)
(S-16)
[11] Stand Shaft (L)
[11] Stand Shaft (R)
(S-15)
(S-17)
(S-16)
(S-15)
Fig. D4
4-5 A81H1DC
TV Cable Wiring Diagram
To LCD Module Assembly
Inverter Power CBA
CN751 CN752
CN701
CN702
CN500
CN501
CN206
CN753
CN200
Digital Main CBA Unit
CN4201 CN3707
CN3701
CN3705CN3702CN3601
CN201 CN202 CN203
Side Jack CBA
CL7002B
Jack CBA
CN7001
Power Supply CBA
Junction CBA
IR Sensor CBA
CL101A
CN100 CL101B
CL106A
CN801
CL7002A
CN802
CN204
To Speaker
Function CBA
CL106B
Fig. D5
4-6 A81H1DC

ELECTRICAL ADJUSTMENT INSTRUCTIONS

General Note: “CBA” is abbreviation for “Circuit Board Assembly.”
Note: Electrical adjustments are required after
replacing circuit components and certain mechanical parts. It is important to perform these adjustments only after all repairs and replacements have been completed. Also, do not attempt these adjustments unless the proper equipment is available.
Test Equipment Required
1. DC Voltmeter
2. NTSC Pattern Generator (Color Bar W/White Window, Red Color, Dot Pattern, Gray Scale, Monoscope, Multi-Burst)
3. Remote control unit
4. Color Analyzer
How to make the Service remote control unit:
Cut “A” portion of the attached remote control unit as shown in Fig. 1.
How to set up the service mode:
Service mode:
1. Use the service remote control unit.
2. Turn the power on.
3. Press the service button on the service remote control unit. The following screen appears.
"*" differs depending on the models.
Ver :
***********************
Boot
Push 0 key
System
Push 0 key
Pic Ver :
*********************** ***********************
Picture :
Push 0 key
Submicon Ver :
******
service button
A
Fig. 1
5-1 A81H1EA
1. Purity Check Mode
This mode cycles through full-screen displays of red, green, blue, and white to check for non-active pixels.
1. Enter the Service mode.
2. Each time pressing [7] button on the service remote control unit, the display changes as follows.
Purity Check Mode
White mode
[7] button
The following adjustment normally are not attempted in the field. Only when replacing the LCD Panel then adjust as a preparation.
2. White Balance Adjustment
Purpose: To mix red, green and blue beams correctly
for pure white. Symptom of Misadjustment: White becomes bluish
or reddish.
Tes t Po int
Screen
Adj. Point Mode Input
White Purity
[CH. o/p]
buttons
[VIDEO1]
C/D
(APL 70%)
or
(APL 25%)
[7] button
Red mode
[7] button
Green mode
[7] button
Blue mode
Note:
When entering this mode, the default setting is White mode.
M. EQ. Spec.
Pattern Generator,
Color analyzer
x= 0.272 ± 0.005 y= 0.278 ± 0.005
Figure
It carries out in a darkroom.
Perpendicularity
L = 3 cm
INPUT: WHITE 70%, 25%
Color Analyzer
1. Operate the unit for more than 20 minutes.
2. Input the White Purity.
INPUT SIGNAL
25%=25IRE
70%=70IRE
3. Set the color analyzer to the CHROMA mode and bring the optical receptor to the center on the LCD-Panel surface after zero point calibration as shown above. Note: The optical receptor must be set perpendicularly to the LCD Panel surface.
4. Enter the Service mode. Press [VOL. n] button on the service remote control unit and select “C/D” mode.
5-2 A81H1EA
5. [CUTOFF] Press [3] button to select “COB” for Blue Cutoff adjustment. Press [1] button to select “COR” for Red Cutoff adjustment.
[DRIVE]
Press [6] button to select “DB” for Blue Drive adjustment. Press [4] button to select “DR” for Red Drive adjustment.
6. In each color mode, press [CH. o / p] buttons to adjust the values of color.
7. Adjust Cutoff and Drive so that the color temperature becomes 12000K (x
0.278 ±0.005).
=
0.272 / y
=
5-3 A81H1EA
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