Panasonic TX-15LT2M User manual

Power Source
AC 100~240V, 50/60Hz
Power Consumption
Average use: 49W
Stand-by condition: 4W
TV set: DC 15V, 2.8 A max.
LCD
15.2-inch (385mm), 16:9 aspect ratio LCD panel
Screen Size
13.21-inch (335.6mm) (W) x 7.43-inch (188.6mm)(H) x 15.2-
inch (385.0mm)(Diagonal)
Sound
Speaker
Tweeter (3 x 4cm 2pcs, 89), Woofer (Ø5cm, 89)
Audio Output
6.5W (2.0W+2.0W+2.5W (Woofer)), 10%THD
Headphones
M3(3.5 mm) Jack x 1 89impedance
FEATURES
Aero-Hammer®Woofer System (2Way 3Speaker System)
©2003 Matsushita Electric Industrial Co., Ltd. All
rights reserved. Unauthorized copying and
distribution is a violation of law.
TX-15LT2M
TX-15LT2Q
TX-15LT2Z
TX-15LT2X
TX-15LT2T
LH1 Chassis
Receiving System
Receiving Channels
Regular TV
VHF BAND
2-12 (PAL/SECAM B, K1)
0-12 (PAL B AUST.)
1-9 (PAL B N.Z)
1-12 (PAL/SECAM D)
1-12 (NTSC M Japan)
2-13 (NTSC M U.S.A)
UHF BAND
21-69 (PAL G, H, I/SECAM G, K, K1)
28-69 (PAL B AUST.)
13-57 (PAL D, K)
15.2” Diagonal LCD TV
Specifications
ORDER NO. ITD0303001C2

13-62 (NTSC M Japan)
14-69 (NTSC M U.S.A)
14-69 (NTSC M U.S.A)
CATV
S1-S20 (OSCAR)
1-125 (U.S.A CATV)
C13-C49 (JAPAN)
S21-S41 (HYPER)
Z1-Z37 (CHINA)
5A, 9A (AUST.)
Aerial-Rear
UHF/VHF
Operating Conditions
Temperature: 5-40°C
Humidity: 5%-90% RH (non-condensing)
Connection Terminals
AV1
21 Pin socket
(Audio/ Video in, TV out, RGB in)
AV2
1 Safety Precautions 4
1.1. General Guidelines 4
2 Prevention of Electro Static Discharge (ESD) to
Electrostatically Sensitive (ES) Devices 5
3 About lead free solder (PbF) 6
4SelfCheck 7
5 SERVICE HINTS 7
5.1. Hotel Mode 7
6 Chasis Board Layout 8
7 Servicing method 9
7.1. Removing tilt base 9
7.2. Removing rear panel 10
7.3. Removing speaker unit 10
7.4. Removing front panel 11
7.5. Removing LCD panel 11
7.6. Removing main A-Board 12
7.7. Removing B-Board (with tuner assembly) 13
7.8. Removing DG-Board 14
7.9. Removing H-Board 14
7.10. Removing P-Board 15
7.11. Removing K-Board 15
7.12. Pull out the flexible cable straight to the coupler. 15
7.13. Removing back-light 16
7.14. A-Board servicing 16
8 Service Mode Function 17
VIDEO
RCA PIN Type x 1
S-VIDEO
Mini DIN 4-pin
AUDIO L-R
RCA PIN Type × 2
AUDIO OUT
3.5mm, Stereo Jack 0.5Vrms
Dimensions (W x H x D)
Including TV Stand
413mm x 330mm x 180mm
TV Set Only
413mm x 295mm x 73mm
Weight (Mass)
5.6kg Net
Storage Conditions
Temperature: 55°C MAX
Note:
Design and Specifications are subject to change without notice.
Weight and Dimensions shown are approximate.
8.1. How to enter SERVICE 1 17
8.2. How to enter SERVICE 2 17
8.3. Option Description 19
8.4. Option Code Setting 21
9 Adjustment 22
9.1. RF AGC Adjustment 22
9.2. DVCO Adjustment 22
10 Conductor Views 23
10.1. A-Board 23
10.2. B, H, K, P and V-Board 25
10.3. DG-Board 27
11 Block and Schematic Diagrams 29
11.1. Schematic Diagram Notes 29
11.2. Power Block Diagram 30
11.3. Signal Block Diagram 32
11.4. A-Board (1 of 4) Schematic Diagram 34
11.5. A-Board (2 of 4) Schematic Diagram 35
11.6. A-Board (3 of 4) Schematic Diagram 36
11.7. A-Board (4 of 4) Schematic Diagram 37
11.8. DG-Board (1 of 5) Schematic Diagram 38
11.9. DG-Board (2 of 5) Schematic Diagram 39
11.10. DG-Board (3 of 5) Schematic Diagram 40
11.11. DG-Board (4 of 5) Schematic Diagram 41
11.12. DG-Board (5 of 5) Schematic Diagram 42
11.13. B, H, K, and V-Board Schematic Diagram 43
CONTENTS Page Page
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TX-15LT2M / TX-15LT2Q / TX-15LT2Z / TX-15LT2X / TX-15LT2T

11.14. P-Board Schematic Diagram 44
12 Parts Location & Mechanical Replacement Parts List 45
12.1. Parts Location 45
12.2. Packing Exploded View 46
12.3. Mechanical Replacement Parts List 47
13 Replacement Parts List 48
13.1. Replacement Parts List Notes 48
13.2. Electrical Replacement Parts List Notes 49
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TX-15LT2M / TX-15LT2Q / TX-15LT2Z / TX-15LT2X / TX-15LT2T

1.1.1. Leakage Current Cold Check
1.Unplug the AC cord and connect a jumper between the two
prongs on the plug.
2.Measure the resistance value, with an ohmmeter, between
the jumpered AC plug and each exposed metallic cabinet
part on the equipment such as screwheads, connectors,
control shafts, etc. When the exposed metallic part has a
return path to the chassis, the reading should be between
1M9and 5.2M9.
When the exposed metal does not have a return path to
the chassis, the reading must be .
Figure 1
1.1.2. Leakage Current Hot Check (See
Figure 1.)
1.Plug the AC cord directly into the AC outlet. Do not use an
isolation transformer for this check.
2.Connect a 1.5k9, 10 watts resistor, in parallel with a 0.15µF
capacitors, between each exposed metallic part on the set
and a good earth ground such as a water pipe, as shown in
Figure 1.
3.Use an AC voltmeter, with 1000 ohms/volt or more
sensitivity, to measure the potential across the resistor.
4.Check each exposed metallic part, and measure the
voltage at each point.
5.Reverse the AC plug in the AC outlet and repeat each of the
above measurements.
6.The potential at any point should not exceed 0.75 volts
RMS. A leakage current tester (Simpson Model 229 or
equivalent) may be used to make the hot checks, leakage
current must not exceed 1/2 milliamp. In case a
measurement is outside of the limits specified, there is a
possibility of a shock hazard, and the equipment should be
repaired and rechecked before it is returned to the
customer.
1 Safety Precautions
1.1. General Guidelines
1.When servicing, observe the original lead dress. If a short circuit is found, replace all parts which have been overheated or
damaged by the short circuit.
2.After servicing, see to it that all the protective devices such as insulation barriers, insulation papers shields are properly
installed.
3.After servicing, make the following leakage current checks to prevent the customer from being exposed to shock hazards.
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TX-15LT2M / TX-15LT2Q / TX-15LT2Z / TX-15LT2X / TX-15LT2T

2 Prevention of Electro Static Discharge (ESD) to
Electrostatically Sensitive (ES) Devices
Some semiconductor (solid state) devices can be damaged easily by static electricity. Such components commonly are called
Electrostatically Sensitive (ES) Devices. Examples of 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 electro static discharge (ESD).
1.Immediately before handling any semiconductor component or semiconductor-equipped assembly, drain off any ESD on your
body by touching a known earth ground. Alternatively, obtain and wear a commercially available discharging ESD wrist strap,
which should be removed for potential shock reasons 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 alminum
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 solder removal device. Some solder removal devices not classified as "anti-static (ESD protected)" can
generate electrical charge 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, alminum 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 hamless motion such as the brushing
together of your clothes fabric or the lifting of your foot from a carpeted floor can generate static electricity (ESD) sufficient to
damage an ES device).
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TX-15LT2M / TX-15LT2Q / TX-15LT2Z / TX-15LT2X / TX-15LT2T

3 About lead free solder (PbF)
Note: Lead is listed as (Pb) in the periodic table of elements.
In the information below, Pb will refer to Lead solder, and PbF will refer to Lead Free Solder.
The Lead Free Solder used in our manufacturing process and discussed below is (Sn+Ag+Cu).
That is Tin (Sn), Silver (Ag) and (Cu) although other types are available.
This model uses Pb Free solder in it’s manufacture due to environmental conservation issues. For service and repair work, we’d
suggest the use of Pb free solder as well, although Pb solder may be used.
PCBs manufactured using lead free solder will have the PbF within a leaf Symbol stamped on the back of PCB.
Caution


·

Pb free solder has a higher melting point than standard solder. Typically the melting point is 50 ~ 70 °F (30 ~ 40 °C) higher.
Please use a high temperature soldering iron and set it to 700 ± 20 °F (370 ± 10 °C).


·

Pb free solder will tend to splash when heated too high (about 1100 °F or 600 °C).
If you must use Pb solder, please completely remove all of the Pb free solder on the pins or solder area before applying Pb
solder. If this is not practical, be sure to heat the Pb free solder until it melts, before applying Pb solder.


·

After applying PbF solder to double layered boards, please check the component side for excess solder which may flow onto
the opposite side. (see figure below)
Suggested Pb free solder
There are several kinds of Pb free solder available for purchase. This product uses Sn+Ag+Cu (tin, silver, copper) solder.
However, Sn+Cu (tin, copper), Sn+Zn+Bi (tin, zinc, bismuth) solder can also be used.
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TX-15LT2M / TX-15LT2Q / TX-15LT2Z / TX-15LT2X / TX-15LT2T

4SelfCheck
1.Self-Check is used to automatically check the bus lines and hexadecimal code of the TV set.
2.To get into the Self -Check mode press the [ Down ( ) ] button on the customer controls at the front of the set, at the same
time pressing the [ SET UP ] button on the remote control, and the screen will show :
If the CCU ports have been checked and found to be incorrect or not located then “--” will appear in place of “O.K.”.
5 SERVICE HINTS
5.1. Hotel Mode
Purpose
1.At Hotels, this Mode prevent customer from changing the TV preset data, such as Channel preset data.
Note:
This Mode is useful for hotel, you should not get into “Hotel Mode” with Normal use.
Operation
1.To get into “ Hotel Mode”, press “Recall” button on the remote control and Channel up “[ ]” key on the TV set
simultaneously, after setting the “Off-Timer” mode.
2.In this mode, The Channel up and down Function will be able as normal Mode, and The maximum volume level for this
mode is set at the current volume level, that means setting at the level before entering the mode. However, other function
will be disable.
3.To exit This mode, press “SET UP” button on the remote control and the “Volume Down [ ]” key on the TV set
simultaneously.
* This Information is informed by Service Manual only.
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TX-15LT2M / TX-15LT2Q / TX-15LT2Z / TX-15LT2X / TX-15LT2T

6 Chasis Board Layout
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TX-15LT2M / TX-15LT2Q / TX-15LT2Z / TX-15LT2X / TX-15LT2T

7 Servicing method
7.1. Removing tilt base
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TX-15LT2M / TX-15LT2Q / TX-15LT2Z / TX-15LT2X / TX-15LT2T

7.2. Removing rear panel
7.3. Removing speaker unit
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TX-15LT2M / TX-15LT2Q / TX-15LT2Z / TX-15LT2X / TX-15LT2T