Haier DX-RCRT20-09 Service Manual
DX-RCRT20-09
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(2007)(Haier Electronic Company Limited)
All rights reserved. Unauthorized copying and distribution is a
violation of law.
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WARNING
This service information is designed for experienced repair technicians only and is not designed for use
by the general public. It does not contain warnings or cautions to advise non-technical individuals of
potential dangers in attempting to service a product. Products powered b electricity should be serviced
or repaired only by experienced professional technicians. Any attempt to service or repair the product
deal with in this service information by anyone else could result in serious injury or death
.
CONTENT
1. SPECIFICATIONS………………………………………………………………………….. 3
2. WAINING…………………………………………………………………………………….. 4
3. FEATURES AND TECHINICAL DESCRIPTION………………………………………... 11
4. Adjustment……………………………………………………………………………………11
5. WIRING CONNECTION DIAGRAM……………………………………………………….14
6. Circuit Explanation…………………………………..…………………..………………….16
7. Maintenance Service and Trouble shooting………………………………………………19
8. Circuit Diagram………………………………………………………………………………24
1. Specification
MODEL
21TA1
MODEL
21TA1
NO.
ITEM
FUNCTION
USA
NO.
ITEM
FUNCTION
USA
1
Main IC R2J10165GF
24
Digital curtain
×
2
CRT
flat 25
Slow fading on & off
×
3
Color system
NTSC+ATSC 26
Semitransparent menu
×
4
Audio system
M 27
Non-flshing channel
changing
√
5
NO.of channels
181 28
ZOOM
√
6
OSD language
ENGLISH 29
16:9 mode
√
7
PICTURE
Multi-picture modes
4 30
Games
×
8
AV ste r e o
√ 31
Calendar
×
9
Super woofer
× 32
Child-lock
×
10
Surrounding sound
× 33
V-CHIP
√
11
Treble/bass boost
× 34
No-picture listening
×
12
Left/right balancer
× 35
Background light
×
13
NICAM
× 36
Sleep timer
√
14
Multi-audio modes
× 37
Q.view
√
15
Tone adjuster
× 38
SOFTWARE
CCD
√
16
MTS/SAP
× 39
NO. of built-in speakers
2
17
AUDIO
Auto-volume leveling
× 40
Audio output power(W)
2×2
18
AV input
back 1,front1 41
Total power input（W）
70
19
AV output
back 1 42
Voltage range（V）
90~250
20
DVD terminal
back 1 43
Power frequency（Hz）
50/60
21
S-video jack
back 1 44
Time of sleep timer(MINS)
240
22
Headphone socket
× 45
Net weight(KG)
24
23
JACK
SCART socket
× 46
Gross weight(KG)
26
47
Net dimension(MM)
576×395×458
48
PARAMET ER
Packaged dimension(MM)
650×565×525
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2. Warning
Safety Precautions
IMPORTANT SAFETY NOTICE
Many electrical identify these parts and mechanical parts in this chassis have special
safety-related characteristics! In the Schematic Diagram and Replacement Parts List.
It is essential that these special safety parts should be replaced with the same
components as recommended in this manual to prevent X-RADIATION, Shock, Fire, or
other Hazards.
Do not modify the original design without permission of the manufacturer.
General Guidance
An Isolation Transformer should always be used during the servicing of a receiver whose
chassis is not isolated from the AC power line. Use a transformer of adequate power rating
as this protects the technician from accidents that might result in personal injury caused by
electrical shocks.
It will also protect the receiver and it’s components from being damaged by accidental
shorts of the circuitry that might be inadvertently introduced during the service operation.
If any fuse (or Fusible Resistor) in this TV receiver is blown, replace it with a specified one.
When replacing a high wattage resistor (Oxide Metal Film Resistor, over 1W), keep the
resistor 10mm away from PCB.
Keep wires away from high voltage or high temperature parts.
Due to the high vacuum and large surface area of the picture tube, extreme care should be
taken in handling the Picture Tube. Do not lift the Picture Tube by its Neck.
X-RAY Radiation
Warning:
The source of X-RAY RADIATION in this TV receiver is the High Voltage Section and the
Picture Tube.
For continued X-RAY RADIATION protection, the replacement tube must be of the same
type as specified in the Replacement Parts List.
Before returning the receiver to the customer,
Always perform an AC leakage current check on the exposed metallic parts of the cabinet,
such as antennas, terminals, etc., to make sure that the set is safe to operate without any
danger of electrical shock.
Warning and Cautions
1. When you clean the TV set, please pull
out the power plug from AC outlet. Don't
clean the cabinet and the screen with
benzene, petrol and other chemicals.
4. To prevent the TV set from firing and
electric shock, don't
make the TV set rain
or moisture.
2.
In order to prolong the using life of the
TV set, please place it on a ventilated
place.
5. Don't open the back cover, otherwise it is
possible to damage the components in the
TV set and harm you.
3.
Don't place the
TV set in the
sunshine or near
heat source.
6. When the TV set isn't going to be used
for long time or it is in thunder and
lightening, please pull out the plug from AC
outlet and the antenna plug from the cover
of the TV set.
Explanation on the display tube
Generally, it is not needed to clean the tube surface. However, if necessary,its surface can be
cleaned with a dry cotton cloth after cutting off the power.Don't use any cleanser. If using hard
cloth, the tube surface will be damaged.
CAUTION: Before servicing receivers covered by this service manual and its supplements
and addenda, read and follow the SAFETY PRECAUTIONS.
NOTE: If unforeseen circumstances create conflict between the following servicing
precautions and any of the safety precautions, always follow the safety precautions.
Remember: Safety First.
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General Servicing Precautions
1. Always unplug the receiver AC power cord from the AC power source before:
a. Removing or reinstalling any component, circuit board module or any other
assembly of the receiver.
b. Disconnecting or reconnecting any receiver electrical plug or other electrical
connection.
c. Connecting a test substitute in parallel with an electrolytic capacitor in the receiver.
CAUTION: A wrong substitution part or incorrect installation polarity of electrolytic
capacitors may result in an explosion hazard.
d. Discharging the picture tube anode.
2. Test high voltage only by measuring it with an appropriate high voltage meter or other
voltage-measuring device (DVM, FETVOM, etc.) equipped with a suitable high voltage
probe. Do not test high voltage by “drawing an arc”.
3. Discharge the picture tube anode only by (a) first connecting one end of an insulated
clip lead to the degaussing or kine aquadag grounding system shield at the point where
the picture tube socket ground lead is connected, and then (b) touch the other end of
the insulated clip lead to the picture tube anode button, using an insulating handle to
avoid personal contact with high voltage.
4. Do not spray chemicals on or near this receiver or any of its assemblies.
5. Unless specified otherwise in this service manual, clean electrical contacts only by
applying the following mixture to the contacts with a pipe cleaner, cotton-tipped stick or
comparable nonabrasive applicator; 10% (by volume) Acetone and 90% (by volume)
isopropyl alcohol (90%-99% strength)
CAUTION: This is a flammable mixture.
Unless specified otherwise in this service manual, lubrication of contacts is not
required.
6. Do not defeat any plug / socket B+ voltage interlocks with which receivers covered by
this service manual might be equipped.
7. Do not apply AC power to this instrument and/or any of its electrical assemblies unless
all solid-state device heat sinks are correctly installed.
8. Always connect the test receiver ground lead to the receiver chassis ground before
connecting the test receiver positive lead.
Always remove the test receiver ground lead last.
9. Use with this receiver only the test fixtures specified in this service manual.
CAUTION: Do not connect the test fixture ground strap to any heat sink in this receiver.
Electrostatic ally Sensitive (ES) Devices
Some semiconductor (solid state) devices can be damaged easily by static electricity.
Such components are usually called Electrostatic ally Sensitive (ES) Devices. Examples of
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typical ES devices are integrated circuits and some field effect transistors and
semiconductor “chip” components. The following techniques should be used to help
reduce the incidence of component damage caused by static electricity.
1. Immediately before handling any semiconductor component or semiconductorequipped assembly, drain off any electrostatic charge on your body by touching a
known earth ground. Alternatively, obtain and wear a commercially available
discharging wrist strap device, which should be removed to prevent potential shock
prior to applying power to the unit under test.
2. After removing an electrical assembly equipped with ES devices, place the assembly
on a conductive surface such as aluminum foil, to prevent electrostatic charge buildup
or exposure of the assembly.
3. Use only a grounded-tip soldering iron to solder or unsolder ES devices.
4. Use only an anti-static type folder removal device. Some solder removal devices not
classified as “anti-static” can generate electrical charges sufficient to damage ES
devices.
5. Do not use freon-propelled chemicals. These can generate electrical charges
sufficient to damage ES devices.
6. Do not remove a replacement ES device from its protective package until immediately
before you are ready to install it. (Most replacement ES devices are packaged with
leads electrically shorted together by conductive foam, aluminum foil or comparable
conductive material).
7. Immediately before removing the protective material from the leads of a replacement
ES device, touch the protective material to the chassis or circuit assembly into which
the device will be installed.
CAUTION: Be sure no power is applied to the chassis or circuit, and observe all other
safety precautions.
8. Minimize bodily motions when handling unpackaged replacement ES devices.
(Otherwise even some normally harmless motions such as mutual brushing of your
clothes’ fabric or lifting of your foot from a carpeted floor might generate static electricity
sufficient to damage an ES device.)
General Soldering Guidelines
Use a grounded-tip, low-wattage soldering iron and appropriate tip size and shape that
will maintain tip temperature within the range of 500
o
F to 600
o
F .
Use an appropriate gauge of RMA resin-core solder composed of 60 parts tin/40 parts
lead.
Keep the soldering iron tip clean and well tinned.
Thoroughly clean the surfaces to be soldered. Use a mall wire bristle (0.5 inch, or 1.25cm)
brush with a metal handle. Do not use Freon -propelled spay-on cleaners.
Use the following unsoldering technique
a. Allow the soldering iron tip to reach normal temperature. (500 o F to 600o F)
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b. Heating the component lead until the solder melts.
c. Quickly draw the melted solder with an anti-static, suction-type solder removal
device with solder braid.
CAUTION: Work quickly to avoid overheating the circuit board printed foil.
Use the following unsoldering technique
a. Allow the soldering iron tip to reach normal temperature. (500 o F to 600o F)
b. First, hold the soldering iron tip and solder the strand against the component lead
until the solder melts.
c. Quickly move the soldering iron tip to the junction of the component lead and the
printed circuit foil, and hold it there only until the solder flows onto and around both
the component lead and the foil.
CAUTION: Work quickly to avoid overheating the circuit board printed foil.
d. Closely inspect the solder area and remove any excess or splashed solder with a
small wire-bristle brush.
Remove /Replacement
Some chassis circuit boards have slotted holes (oblong) through which the IC leads are
inserted and then bent flat against the circuit foil. When holes are of slotted type, the
following technique should be used to remove and replace the IC. When working with
boards using the familiar round hole, use the standard technique as outlined.
Removal
Desolder and straighten each IC lead in one operation by gently prying up on the lead with
the soldering iron tip as the solder melts.
Draw away the melted solder with an anti-static suction-type solder removal device (or with
solder braid) before removing the IC.
Replacement
Carefully insert the replacement IC in the circuit board.
Carefully bend each IC lead against the circuit foil pad and solder it.
Clean the soldered areas with a small wire-bristle brush. (It is not necessary to reapply
acrylic coating to the areas).
“Small-Signal” Discrete Transistor
Removal/Replacement
Remove the defective transistor by clipping its leads as close as possible to the
component body.
Bend into a “U” shape the end of each of three leads remaining on the circuit board.
Bend into a “U” shape the replacement transistor leads.
Connect the replacement transistor leads to the corresponding leads extending from the
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circuit board and crimp the “U” with long nose pliers to insure metal to metal contact then
solder each connection.
Power Output, Transistor Device
Removal/Replacement
Heat and remove all solder from around the transistor leads.
Remove the heat sink mounting screw (if so equipped).
Carefully remove the transistor from the heat sink of the circuit board.
Insert new transistor in the circuit board.
Solder each transistor lead, and clip off excess lead.
Replace heat sink.
Diode Removal/Replacement
Remove defective diode by clipping its leads as close as possible to diode body.
Bend the two remaining leads perpendicularly to the circuit board.
Observing diode polarity, wrap each lead of the new diode round the corresponding lead
on the circuit board.
Securely crimp each connection and solder it.
Inspect (on the circuit board copper side) the solder joints of the two “original” leads. If they
are not shiny, reheat them and if necessary, apply additional solder.
Fuse and Conventional Resistor
Removal/Replacement
1. Clip each fuse or resistor lead at top of the circuit board hollow stake.
2. Securely crimp the leads of replacement component around notch at stake top.
3. Solder the connections
CAUTION: Maintain original spacing between the replaced component and adjacent
components and the circuit board to prevent excessive component temperatures.
Circuit Board Foil Repair
Excessive heat applied to the copper foil of any printed circuit board will weaken the
adhesive that bonds foil to the circuit board causing the foil to separate from or “lift-off” the
board. The following guidelines and procedures should be followed whenever this
condition is encountered.
At IC Connections
To repair a defective copper pattern at IC connections use the following procedure to
install a jumper wire on the copper pattern side of the circuit board. (Use this technique
only on IC connections).
1. Carefully remove the damaged copper pattern with a sharp knife. (Remove only as
much copper as absolutely necessary).
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