XOCECO PH-42T8 User manual

PDP TELEVISION
PH-42T8
America

CONTENTS
Safety Precautions………………………………………………………………………..…....
Alignment instructions. ………………………………….…………………………….….......
Method of software upgrading …………………………………………….……..…………..
Block diagram ……………………………..…..…..…..…..…..…….………….…………....
Working principle analysis of the unit……………………..……………………….…………
Diagnose and service of panel………………………………………………………………..
Wiring diagram……………………………………………………………………………..…..
Assembly list………..…..…..…..…..…..…..…..…..…..…..…..…..…..…..…..…..…..…....
Trouble shooting guide ………………………………………………………..……………...
Schematic diagram …………………………………………………………………….…......
APPENDIX: EXPLODED VIEW
PART LIST
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4
7
8
9
18
21
22
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Safety Precautions
Please read the “Points for attention for the Maintenance & Repair of PDP” and “Criterion for
Identifying the Defects on Screen” as below, before inspecting and adjusting the TV set.
1. “Points for attention for the Maintenance & Repair of PDP”
To avoid possible danger, damage or jeopardy to health and to prevent PDP screen from new
damage, the maintenance people must read the following carefully. If they ignore the following
warnings, there will be deathful risks:
1.1 Screens vary from one model to another and therefore not interchangeable. Be sure to use the
same type of screen in the replacement.
1.2 The operation voltage is approximately 350V for PDP module (including screen, driving circuit,
logic circuit and power module). If you want to conduct maintenance work on PDP module when the
set is in normal operation or just after the power is off, you must take proper measures to avoid
electric shock and never have direct contact or touch with the circuitry of the working module or
metal parts. That’s because within a short time relatively high voltage still remains on the capacitor
of the driving part even after the power is off. Make sure to begin relevant maintenance operation at
least one minute after the power is off.
1.3 Don’t apply on the module any power supply that is higher than the specification. If the power
supply used deviates from the value given in the specification, there might be a possibility of leading
to fire or damage to the module.
1.4 Never have operation or mounting work under unsuitable environment such as areas in the
vicinity of water – bathroom, laundry, water chute of kitchen – sources of fire, heat-radiation parts or
direct exposure to sunlight. Otherwise there will be kickbacks.
1.5 In case foreign substances such as water, liquid, metal slices or others fall into the module
carelessly power must be cut off immediately. Keep the module as it is and do not move anything on
the module. Otherwise it might be possible to contact the high voltage or cause shock short circuit
so that it may lead to fire or electric shock.
1.6 If there is smoke, abnormal smell or sound from the module, please cut the power off
immediately. Likewise in case the screen doesn’t work when the power is on or during the operation,
please also cut off the power at once. No more operation in this case.
1.7 Do not remove or plug its connection wire when the module is in operation or right after the
power is off. That’s because there remains a relatively high voltage on the capacitor of the driving
circuit. If there is a need to remove or plug in the connection wire, please wait at least one minute
after the power is off.
1.8 Considering the module has a glass faceplate, please avoid extrusion by external force lest it
should cause glass breakage that may get people injured. Two people are needed in cooperation to
move this module lest contingency takes place.
1.9 The complete TV set is designed on the basis of full consideration of thermal dissipation by
convection, with the round hole on the top for heat emission. To avoid overheat, please do not have
any covering on the hole during normal operation and never put it in the place where the space is
narrow and in bad ventilation.
1.10 There is quite a number of circuits in PDP that are integrated ones. Please be on guard against
Note: This maintenance manual is intended only for the reference of the maintenance people.
Please pay attention to the following points before carrying out the maintenance work.

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static electricity. During maintenance operation be sure to cover yourself with anti-static bag and
before operation make sure to have it sufficiently grounded.
1.11 There are a big number of connection wires distributed around the screen. Please take care
not to touch or scuff them during maintenance or removing the screen, because once they are
damaged the screen will fail to work and it’s not possible to repair it.
1.12 Connector for the circuit board of the screen part is relatively fine and delicate. Please take
care in the replacement operation lest it should get damaged.
1.13 Special care must be taken during transportation and handling because strenuous vibration
could lead to screen glass breakage or damage on the driving circuitry. Be sure to use a strong
outer case to pack it up before transportation or handling.
1.14 Please put it for storage in an environment in which the conditions are under control so as to
prevent the temperature and humidity from exceeding the scope stipulated in the specification. For
prolonged storage please cover it with anti-moisture bag and have them piled and stored in one
place. The environmental conditions are tabulated as below:
Temperature Scope for operation 0~50centigrade
Scope for storage -15~60centigrade
Humidity Scope for operation 20%~80%
Scope for storage 20%~80%
1.15 If a fixed picture is displayed for a long time, difference in its brightness and color may occur
compared with movable pictures. But it doesn’t show any problem and the reason is that there is
reduced density of fluorescent powder in the former. On the other hand, even if changes take place
in the picture, it can keep its brightness for a period of time (several minutes). It’s a feature inherent
with plasma and it’s not abnormal. However please try as much as possible to avoid showing a still
picture of high brightness for a long time during operation.
1.16 As a digitalized display devise, this module is provided with error diffusion technology and the
gray scale and false enhancement of contour can be displayed by reusing of sub-field. As
compared with cathode ray tube, it can be found in the moving picture that at the brim of the face of
a person there are some wrong colors.
1.17 During the display of graph (indicating the gradual change in brightness horizontally or
vertically) resulting from gray scale test it can be found that the brightness for the two adjacent
levels is uneven. This is caused by the reuse of sub-field, the display of load rectification and the
electrolysis.
1.18 The screen front plate is of glass. Please make sure that the screen has been put in place
during erection. If it is not in place before the erection begins it may lead to screen crack or
breakage.
1.19 Make sure the screw used in the mounting of the screen is of the original specs lest it should
cause damage to the screen due to mismatch. Special care should be taken not to use too long or
too big screw.
1.20 Care must be taken to guard against dust during assembling or dismantling, especially to
avoid dirt from falling in between the screen and the glass lest it should harm the receiving and
viewing effect.
1.21 There is piece of insulator stuck on the rear chassis corresponding to the power supply board.
It is used to isolate the cool part from the hot part. Please take care to keep it intact lest it should

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become a potential safety trouble.
1.22 In addition to plasma screen, the glass is a part of high value. It has such functions as
anti-radiation, adjustment of color temperature etc. Please handle it carefully.