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SERVICE MANUAL
1.PRECAUTIONS
Prior to shipment from the factory,the products are strictly inspected to conform with 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.
1-1.Safety Precautions
1) Before returning an instrument to the customer, always and repeat the test.
make a safety check of the entire instrument, including, but
not limited to, the following items:
(1) Be sure that no built-in protective devices are defective
or have been defeated during servicing.
(1) Protective shields are provided to protect both the
technician and the customer. Correctly replace all
missing protective shields, including any remove 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 fish papers,
AC Leakage Test
adjustment and compartment covers/shields, and
isolation resistor/capacitor networks. Do not operate
Any measurements not within the limits specified
this instrument or permit it to be operated without all
herein indicate a potential shock hazard that must be
protective devices correctly installed and functioning.
eliminated before returning the instrument to the
customer.
(2) Be sure that there are no cabinet opening through which
adults or children might be able to insert their fingers
(4) Insulation Resistance Test Cold Check-(1) Unplug the
and contact a hazardous voltage. Such openings
power supply cord and connect a jumper wore
include, but are not limited to, excessively wide
between the two prongs of the plug. (2) Turn on the
cabinet ventilation slots, and an improperly fitted
power switch of the instrument. (3) Measure the
and/or incorrectly secured cabinet back cover.
resistance with an ohmmeter between the jumpered
AC plug and all exposed metallic cabinet parts on the
(3) Leakage Current Hot Check-With the instrument
instrument, such as screwheads, antenna, control
completely reassembled, plug the AC line cord
shafts, handle brackets, etc. When an exposed
directly into a 120V AC outlet. (Do not use an
metallic part has a return path to the chassis, the
isolation transformer during this test.) Use a leakage
reading should be between 1 and 5.2 megohm. When
current tester or a metering system that complies with
there is no return path to the chassis, the reading must
American National Standards institute (ANSI) C101.1
be infinite. If the reading is not within the limits
Leakage.
specified, there is the possibility of a shock hazard,
and the instrument must be re-pared and rechecked
Current for Appliances and underwriters Laboratories
before it is returned to the customer.
(UL) 1270 (40.7). With the instrument's 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 cabinets,
screwheads, metallic overlays, control shafts, etc.),
especially and exposed metal parts that offer an
electrical return path to the chassis.
Any current measured must not exceed 0.5mA.
Reverse the instrument power cord plug in the outlet
voltage, and (5) antenna wiring. Always inspect in all
areas for pinched, out-of-place, or frayed wiring. Do
not change spacing between a component and the
printed-circuit board, Check the AC power cord for
damage.
5) Components, parts, and/or wiring that appear to have
overheated or that are otherwise damaged should be
replaced with components, parts and/or wiring that
Insulation Resistance Test meet original specifications. Additionally determine
the cause of overheating and/or damage and, if
2) Read and comply with all caution and safety related necessary, take corrective action to remove and
notes non or inside the cabinet, or on the chassis. potential safety hazard.
3) Design Alteration Warning-Do not alter of add to the 6) Product Safety Notice-Some electrical and mechanical
mechanical or electrical design of this instrument. parts have special safety-related characteristics which
Design alterations and additions, including but not are often not evident from visual inspection, nor can
limited to, circuit modifications and the addition of the protection they give necessarily be obtained by
items such as auxiliary audio output connections, replacing them with components rated for higher
might alter the safety characteristics of this instrument voltage, wattage, etc. Parts that have special safety
and create a hazard to the user. Any design alterations characteristics are identified by shading, an ( ) or a
or additions will make you, the service, responsible ( ) on schematics and parts lists. Use of a substitute
for personal injury or property damage resulting there replacement that does not have the same safety
from. characteristics as the recommended replacement part
might created shock, fire and/or other hazards.
4) Observe original lead dress. Take extra care to assure Product safety is under review continuously and new
correct lead dress in the following areas: instructions are issued whenever appropriate.
(1) near sharp edges, (2) near thermally hot parts (be
sure that leads and components do not touch
thermally hot parts), (3) the AC supply, (4) high
1-2 Servicing Precautions
CAUTION: Before servicing Instruments covered by this b. Do not defeat any plug/socket B+ voltage interlocks
service manual and its supplements, read and follow the with which instruments covered by this service
Safety Precautions section of this manual. manual might be equipped.
c. Do not apply AC power to this instrument and/or any
Note: If unforeseen circument create conflict between the of its electrical assemblies unless all solid-state
following servicing precautions and any of the safety device heat sinks are correctly installed.
precautions, always follow the safety precautions. d. Always connect a test instrument's ground lead to
Remember; Safety First the instrument chassis ground before connecting the
test instrument positive lead. Always remove the test
1-2-1 General Serving Precautions instrument ground lead last.
(1) a. Always unplug the instrument's AC power cord from Note: Refer to the Safety Precautions section ground
the AC power source before (1) removing or lead last.
reinstalling any component, circuit board, module or (2) The service precautions are indicated or printed on the
any other instrument assembly. (2) disconnecting cabinet, chassis or components. When servicing,
any instrument electrical plug or other electrical follow the printed or indicated service precautions
connection. (3) connecting a test substitute in and service materials.
parallel with an electrolytic capacitor in the (3) The components used in the unit have a specified flame
instrument. resistance and dielectric strength.
When replacing components, use components which
have the same ratings, by ( ) or by ( ) in the accessible conductive parts.
circuit diagram are important for safety or for the
characteristics of the unit. Always replace them with 1-2-2 Insulation Checking Procedure
the exact replacement components. Disconnect the attachment plug from the AC outlet and
(4) An insulation tube or tape is sometimes used and some turn the power ON. Connect the insulation resistance meter
components are raised above the printed wiring board (500V) to the blades of the attachment plug. The insulation
for safety. The internal wiring is sometimes clamped resistance between each blade of the attachment plug and
to prevent contact with heating components. Install accessible conductive parts (see note) should be more than
such elements as they were. 1 Megohm.
(5) After servicing, always check that the removed screws,
components, and wiring have been installed correctly Note: Accessible conductive parts include metal panels,
and that the portion around the serviced part has not input terminals, earphone jacks, etc.
been damaged and so on. Further, check the insulation
between the blades of the attachment plus and
1-3 ESD Precautions
Electrostatically Sensitive Devices (ESD) devices.
(6) Do not remove a replacement ESD device from its
Some semiconductor (solid static electricity) devices can protective package until immediately before you are
be damaged easily by static electricity. ready to install it. (Most replacement ES devices are
Such compo9nents commonly are called Electrostatically packaged with leads electrically shorted together by
Sensitive Devices (ESD). Examples of typical ESD devices conductive foam, aluminum foil or comparable
are integrated circuits and some field-effect transistors and conductive materials).
semiconductor chip components. The following techniques
of component damage caused by static electricity. (7) Immediately before removing the protective materials
from the leads of a replacement ES device touch the
(1) immediately before handling any semiconductor protective material to the chassis or circuit assembly
components or semiconductor-equipped assembly, into which the device will be installed.
drain off any electrostatic charge on your body by
touching a known earth ground. Alternatively, obtain CAUTION: Be sure no power is applied to the chassis or
and wear a commercially available discharging wrist circuit, and observe all other safety precautions.
strap device, which should be removed for potential
shock reasons prior to applying power to the unit (8) Minimize bodily motions when handling unpackaged
under test. replacement ESD devices. (Otherwise harmless
motion such as the brushing together of your clothes
(2) after removing an electrical assembly equipped with fabric or the lifting of your foot from a carpeted floor
ESD devices, place the assembly on a conductive can generate static electricity sufficient to damage an
surface such as aluminum foil, to prevent electrostatic ESD device).
charge buildup or exposure of the assembly.
(3) Use only a grounded-tip soldering iron to solder or
unsolder ESD device.
(4) Use only an anti-static solder removal devices. Some
solder removal devices not classified as "anti-static"
can generate electrical charges sufficient to damage
ESD devices.
(5) Do not use freon-propelled chemicals. These can
generate electrical charges sufficient to damage ESD
1-4. Handling the LCD Module
In case the screen is damaged and the internal liquid 4. Glass is used in the panel ,so be careful not to drop it
leaks,do not suck or drink the internal fuid. Nor do you or let it strike a hard object ,which could cause
touch it either ,otherwise you might be poisoned or get a breakage or cracks.
rash with your skin,If the internal fluid enters your
mouth,rinse with water.If itadheres to your skin or
clothes,wipe it away with alcohol and then wash with water.
If it enters your eyes,wash with running water immediately.
Precautions for handling the LCD module
The LCD module can be easily damaged during assembly
or disassembly.Observe the following precautions when
handling the LCD module:
1. When installing the LCD module in the LCD cover,be
sure to seat it so that it is properly aligned and
maximum visibility of the display is maintained.
5. CMOS-LSI circuits are used in the module,so guard
against damage from electrostatic discharge.Be sure to
wear aa wrist or ankle ground when handling the
module.
2. If the panel's surface gets dirty,wipe it with cotton or a
soft cloth.If it is still dirty,try breathing on the surface
to create a light condensate and wipe it again.If the
surface is very dirty,we recommend a CRT cleaning
agent.Apply the agent to a cloth and then wipe the
panel's surface .Do not apply cleanser directly to the
panel .Also,neverscratch the suface. 6. Do not expose the module to direct sunlight or strong
ultraviolet rays for long periods.
3. If water or other liquid is left on the panel's surface for 7. Do not store the module a temperatures below
a long period,it can change the screen's tint or stain it. specifications.Cold can cause the liquid crystals to
Be sure to quickly wipe off any liquid. freeze,lose their elasticity or otherwise suffer damage.
8. Do not disassemble the LCD module.Disassembly can 9. If you transport the module,do not use packing
cause malfunctions. material that contains epoxy resin(amine)or silicom
glue(alcohol or oxime).These materials can release gas
that can damage the panel's polarization.
TR901E-1(EURO+DVB-T+DVD) SPECIFICATION
CONTENT
PAGE ITEM
1 CONTENT
1 REVISION HISTORY
2 GENERAL DISCRIPTION
2 FEATURES
3 FUNCTION LAYOUT
5 PCB DIMENSIONS
5 IR CONTROL SCHEMATICS
6 KEY BOARD SCHEMATICS
6 INTERFACE DEFINITION
10 CONFIGURATION & GENERAL PRECAUTIONS
REVISION HISTORY
VERSION DATE PAGE DISCRIPTION AUTHOR
1.0 08.09.10 All First issued Liu Lili
1.1 08.11.13 P8 Correct the description of CN28 JinhuaHuang
-1-
TR901E-1(EURO+DVB-T+DVD) SPECIFICATION
1. GENERAL DESCRIPTION
TR901E-1 is a multi-purpose LCD&PDP control board. It is suitable for UK market. It supports
26~47 inch LCD panel with dual/single LVDS interface and its resolution is up to 1920x1080.
TR901E-1 supports DVB-T Teletext, Nicam, PIP, dual HDMI, dual SCART , YPbPr/YCbCr, PC and
other functions.
TR901E-1 provides expansible functions such as DVD and Card reader.
2. FEATURES
CHIPSET AX68+ZRA39162
MARKET AREA Europe, UK
OSD LANGUAGE English, French, Spanish, Italian, Portuguese, German.(Option)
Interface Dual/Single LVDS interface
PANEL
Resolution Up to 1920x1080(It does not support 10Bit Panel.)
Tuner receiving range 49MHz