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PLASMA TV
SERVICE MANUAL
CHASSIS : RF-043B

MODEL : RT-42PX12X/XH


CAUTION
BEFORE SERVICING THE CHASSIS,
READ THE SAFETY PRECAUTIONS IN THIS MANUAL.
CONTENTS




SAFETY PRECAUTIONS ...................................................................................3

DESCRIPTION OF CONTROLS ........................................................................ 4

SPECIFICATIONS ............................................................................................ 13

ADJUSTMENT INSTRUCTIONS ......................................................................14

TROUBLE SHOOTING GUIDE ..........................................................................19

BLOCK DIAGRAM .............................................................................................30

EXPLODED VIEW ..............................................................................................32

EXPLODED VIEW PARTS LIST ........................................................................33

REPLACEMENT PARTS LIST...........................................................................34

SCHEMATIC DIAGRAM ........................................................................................

PRINTED CIRCUIT BOARD ..................................................................................




- 2 -
SAFETY PRECAUTIONS

IMPORTANT SAFETY NOTICE
Many electrical and mechanical parts in this chassis have special safety-related characteristics. These parts are identified by 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 manufacturer.



General Guidance Leakage Current Hot Check (See below Figure)
Plug the AC cord directly into the AC outlet.
An isolation Transformer should always be used during Do not use a line Isolation Transformer during this check.
the servicing of a receiver whose chassis is not isolated from Connect 1.5K/10watt resistor in parallel with a 0.15uF capacitor
the AC power line. Use a transformer of adequate power rating between a known good earth ground (Water Pipe, Conduit, etc.)
as this protects the technician from accidents resulting in and the exposed metallic parts.
personal injury from electrical shocks. Measure the AC voltage across the resistor using AC
voltmeter with 1000 ohms/volt or more sensitivity.
It will also protect the receiver and it's components from being Reverse plug the AC cord into the AC outlet and repeat AC
damaged by accidental shorts of the circuitry that may be voltage measurements for each exposed metallic part. Any
inadvertently introduced during the service operation. voltage measured must not exceed 0.75 volt RMS which is
corresponds to 0.5mA.
If any fuse (or Fusible Resistor) in this monitor is blown, replace In case any measurement is out of the limits specified, there is
it with the specified. possibility of shock hazard and the set must be checked and
repaired before it is returned to the customer.
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. Leakage Current Hot Check circuit

Due to high vacuum and large surface area of picture tube,
AC Volt-meter
extreme care should be used in handling the Picture Tube.
Do not lift the Picture tube by it's Neck.

Good Earth Ground
such as WATER PIPE,
Leakage Current Cold Check(Antenna Cold Check) To Instrument's CONDUIT etc.
With the instrument AC plug removed from AC source, 0.15uF
exposed
connect an electrical jumper across the two AC plug prongs. METALLIC PARTS
Place the AC switch in the on position, connect one lead of
ohm-meter to the AC plug prongs tied together and touch other
ohm-meter lead in turn to each exposed metallic parts such as 1.5 Kohm/10W
antenna terminals, phone jacks, etc.
If the exposed metallic part has a return path to the chassis, the
measured resistance should be between 1M and 5.2M.
When the exposed metal has no return path to the chassis the
reading must be infinite.
An other abnormality exists that must be corrected before the
receiver is returned to the customer.




- 3 -
DESCRIPTION OF CONTROLS


- When using the remote control aim it at the remote control sensor of the set.
- There's maybe a defect in consecutive operation of remote control in specified brightness according to this set feature.



MUTE POWER
Switches the sound on or off. switches the set on from standby or
off to standby.
MULTIMEDIA MUTE POWER
Selects the Component, RGB or DVI I/II
modes. Selects the language during dual lan-
TV/AV MULTIMEDIA I/II
guage broadcast.
TV/AV Selects the sound output.
Selects the TV, AV, Component, RGB
or DVI modes. ARC
LIST ARC MENU Changes the picture format.
LIST
Displays the program table.
MENU
Displays on screen menus one by
one.
Exits the current menu.
PR Memorizes menu changes.
D / E (Programme Up/Down)
selects a programme or a menu item.
switches the set on from standby. OK
VOL VOL
F / G (Volume Up/Down)
adjusts the volume. PR
adjusts menu settings.
OK
accepts your selection or displays the NUMBER buttons
current mode.
1 2 3

SSM
4 5 6 To select the sound appropriate to
your viewing programme character.
PSM 7 8 9
Adjusts the factory preset picture
according to the room.
PSM 0 SSM
SPLIT ZOOM SLEEP
Enlarge the screen with regular SPLIT ZOOM PIP/DW SLEEP Sets the sleep timer.
ration.
REVEAL PIP PR+ TEXT/
PIP/DW ? TEXT
These buttons are used for teletext.
Switches the sub picture on or off. WIN. SIZE PIP PR- MIX For further details, see the `Teletext'
Selects PIP or DW modes. section.
PIP PR + /- Note : In teletext mode, the PIP PR
Selects a programme for the sub picture. POSITION SWAP TIME
+/-, SWAP and PIP INPUT buttons are
SWAP used for teletext function.
Alternates between main and sub pic- HOLD PIP INPUT INDEX
ture. i
PIP INPUT
Selects the input mode for the sub pic- SWAP
ture. Returns to the previously viewed
programme.
WIN.SIZE Note : This function works only
Adjusts the sub picture size. when Favorite programme is set to Off.
POSITION Otherwise each press of this button
Moves the sub picture to D / E or F / G will select a stored favorite pro-
direction. gramme.




- 4 -
- Shown is a simplified representation of the set.
- Here shown may be somewhat different from your set.






ON/OFF




TV/AV MENU VOL PR



or




TV/AV MENU VOL PR




Main Power Button
MENU
Displays on screen menus one by one.
Remote Control Sensor Exits the current menu.
Memorizes menu changes.


TV/AV Button
Selects the TV, AV, Component,
RGB or DVI modes. If OSD is dis-
played, selects menu item.

D / E (Programme Up/Down)
Power Standby Indicator selects a programme or a menu item.
Illuminates red in standby switches the set on from standby.
mode, Illuminates green F / G (Volume Up/Down)
when the set is turned on adjusts the volume.
adjusts menu settings.



- 5 -





AV2




S-VIDEO
VIDEO
8




R AUDIO L/MONO
AC INPUT
COMPONENT MONITOR Antenna
INPUT 2 OUTPUT

REMOTE RS-232C INPUT DVI INPUT AUDIO INPUT RGB INPUT
COMPONENT A/V
CONTROL (CONTROL/SERVICE) INPUT 1 INPUT1
S-VIDEO
R L R L/MOND

VIDEO AUDIO AUDIO VIDEO




1 2 3 4 5 6 7




1. CONTROL LOCK / REMOTE CONTROL 6. ANTENNA INPUT

2. RS-232C INPUT(CONTROL/SERVICE) PORT 7. POWER CORD SOCKET
Connect to the RS-232C port on a PC. This Monitor operates on an AC power. The voltage is indi-
cated on the Specifications page. Never attempt to operate
3. DVI INPUT / AUDIO INPUT / RGB INPUT the Monitor on DC power.
Connect the monitor output socket of the PERSONAL COM-
PUTER to this socket. 8. AUDIO/VIDEO IN SOCKETS (AV2)
S-VIDEO/AUDIO IN SOCKETS
4. COMPONENT INPUT
Connect DVD video outputs to Y, PB, PR of COMPONENT
INPUT and audio outputs to Audio sockets of AUDIO INPUT.

5. AUDIO/VIDEO IN SOCKETS (AV1)
Connect the audio/video out sockets of external equipment to
these sockets.
S-VIDEO/AUDIO IN SOCKETS
Connect the S-VIDEO out socket of an VCR to the S-VIDEO
socket.
Connect the audio out sockets of the VCR to the audio sock-
ets as in AV1.




- 6 -
Antenna Connection
- Be careful for the bronze wire not to be bended in connecting to antenna input port.


Apartments
(connecting to wall antenna socket)


wall antenna socket
VIDEO AUDIO AUDIO VIDEO
R L R L/MOND AC INPUT
COMPONENT MONITOR Antenna
INPUT 2 OUTPUT
INPUT AUDIO INPUT RGB INPUT
COMPONENT A/V
INPUT 1 INPUT1
S-VIDEO


RF coaxial wire (75 ohms)
< Back panel of the set >
VHF antenna
UHF antenna
outdoor antenna




Private house
(connecting to wall outdoor antenna)




Watching VCR
- When connecting the Monitor to external equipment, match the colours of connecting ports (Video - yellow, Audio (L) - white,
Audio (R) -red).
- Connect the VIDEO INPUT socket (yellow) to the VIDEO INPUT on the set.
- If you have a mono VCR, connect the audio cable from the VCR to the AUDIO (L/MONO) input on the set.
- If you connect an S-VIDEO VCR to the S-VIDEO input, the picture quality is improved; compared to connecting a regular VCR
to the Video input.
- Use the orbiter function to Avoid having a fixed image remain on the screen for a long period of time. Typically a frozen still pic-
ture from a VCR. (Refer to p. 25)
If a 4:3 picture format is used; the fixed image may remain visible on the screen.
- To avoid picture noise (interference), leave an adequate distance between the VCR and set.


Watching TV programmes < Back panel of the set >
- Turn the set on and select the programme you
want.
Watching VCR
1. Use the TV/AV button on the remote control to
select AV1 or AV2.
- If both S-VIDEO and VIDEO sockets have been
AC IN
connected to the S-VHS VCR simultaneously, only RGB INPUT
COMPONENT
INPUT 2
MONITOR
OUTPUT
Antenna




the S-VIDEO can be received. COMPONENT
INPUT 1
R L R L/MOND
A/V
INPUT1
S-VIDEO



2. Insert a video tape into the VCR and press the VIDEO AUDIO AUDIO VIDEO


PLAY button on the VCR.
(See VCR owner's manual)




< VCR >




- 7 -
Watching Cable TV
- After subscribing for a local cable TV station and installing a converter you can watch cable TV.
- For further information of cable TV, contact the local cable TV station.

< Back panel of the set > To watch cable TV

1. Use the TV/AV button on the remote control to
select AV1 or AV2.
2. Tune to cable service provided channels using
the cable box.

AC INP
COMPONENT MONITOR Antenna
INPUT 2 OUTPUT
RGB INPUT
COMPONENT A/V
INPUT 1 INPUT1
S-VIDEO
R L R L/MOND

VIDEO AUDIO AUDIO VIDEO




< Cable box >




Watching external AV source
- When connecting the set to an external source, match the colours of AUDIO/VIDEO input jacks on the set with the output jacks
on the audio/video equipment: Video = yellow, Audio (Left) = white, Audio (Right) = red.


How to use < Back panel of the set >
1. Use the TV/AV button on the remote control to
select AV1 or AV2.
2. Operate the corresponding external equipment.
See external equipment operating guide.


COMPONENT MONITOR An
INPUT 2 OUTPUT
AUDIO INPUT RGB INPUT
COMPONENT A/V
INPUT 1 INPUT1
S-VIDEO
R L R L/MOND

VIDEO AUDIO AUDIO VIDEO




Camcorder
R AUDIO L VIDEO




Video game set




- 8 -
Watching DVD
How to connect < Back panel of the set >
Connect DVD video outputs to Y, PB, PR of COMPO-
NENT INPUT and audio outputs to Audio sockets of
AUDIO INPUT.
How to use R R




1. Turn on the DVD player, and insert a DVD.
2. Use TV/AV or MULTIMEDIA button on the remote
AC INPU
control to select Component 1 or Component 2. Refer to COMPONENT
INPUT 2
MONITOR
OUTPUT
Antenna

UT RGB INPUT
the DVD player's manual for operating instructions. COMPONENT
INPUT 1
R L R L/MOND
A/V
INPUT1
S-VIDEO


VIDEO AUDIO AUDIO VIDEO