LG MT-50PZ41VB, MT-50PZ41, MT-50PZ41VS, MT-50PZ43, MZ-50PZ43 Service Manual

...

OKVOLCH

PLASMA MONITOR

SERVICE MANUAL

CAUTION

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

CHASSIS : RF-02CA

MODEL : MT-50PZ40

MODEL : MT-50PZ41/H/V/VB/VS MODEL : MT/MZ-50PZ43/M/S/V/VS MODEL : MZ-50PZ42/42S

website:http://biz.LGservice.com

e-mail:http://www.LGEservice.com/techsup.html

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CONTENTS

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

DISCRIPTION OF CONTROLS ......................................................................... 4

ADJUSTMENT INSTRUCTIONS ........................................................................8

BLOCK DIAGRAM.............................................................................................11

EXPLODED VIEW..............................................................................................12

EXPLODED VIEW PARTS LIST........................................................................13

REPLACEMENT PARTS LIST...........................................................................14

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

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

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SAFETY PRECAUTIONS

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

An lsolation 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 resulting in personal injury from electrical shocks.

It will also protect the receiver and it's components from being damaged by accidental shorts of the circuitary that may be inadvertently introduced during the service operation.

If any fuse (or Fusible Resistor) in this monitor is blown, replace it with the specified.

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

Leakage Current Cold Check(Antenna Cold Check)

With the instrument AC plug removed from AC source, connect an electrical jumper across the two AC plug prongs. Place the AC switch in the on positioin, 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 antenna terminals, phone jacks, etc. If the exposed metallic part has a return path to the chassis, the measured resistance should be between 1MΩ and 5.2MΩ. 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.

Leakage Current Hot Check (See below Figure)

Plug the AC cord directly into the AC outlet.

Do not use a line Isolation Transformer during this check.

Connect 1.5K/10watt resistor in parallel with a 0.15uF capacitor between a known good earth ground (Water Pipe, Conduit, etc.) and the exposed metallic parts. Measure the AC voltage across the resistor using AC voltmeter with 1000 ohms/volt or more sensitivity. Reverse plug the AC cord into the AC outlet and repeat AC voltage measurements for each esposed metallic part. Any voltage measured must not exceed 0.75 volt RMS which is corresponds to 0.5mA. In case any measurement is out of the limits sepcified, there is possibility of shock hazard and the set must be checked and repaired before it is returned to the customer.

Leakage Current Hot Check circuit

1.5 Kohm/10W

To Instrument's exposed METALLIC PARTS

Good Earth Ground such as WATER PIPE, CONDUIT etc.

AC Volt-meter

IMPORTANT SAFETY NOTICE

0.15uF

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CONTROLS DESCRIPTION

Connection to PC

Connection to AV equipment

AC INPUT

(8Ω)

EXTERNAL SPEAKER

( )( )

COMPONENT(480i/480p)

(DVD INPUT)

AUDIO INPUT

VIDEO INPUT

AUDIO INPUT

RGB1 OUTPUT

(PC OUTPUT)

RGB1 INPUT

(PC INPUT)

RGB2 INPUT

(DIGITAL RGB INPUT)

RS-232C INPUT (CONTROL/SERVICE)

( )( )

S-VIDEO

(8Ω)

EXTERNAL SPEAKER

(MONO)

AUDIO

YPBP

AUDIO

ON/OFF

VOL

INPUT SELECT

Main power button

INPUT SELECT button

VOLUME (FF,GG) buttons

Power standby indicator

Illuminates red in standby mode. Illuminates green when the Monitor is turned on

Remote control sensor

MENU button

DD,EE

buttons

AUDIO INPUT

VIDEO INPUT

COMPONENT (DVD INPUT)

S-VIDEO INPUT

AUDIO INPUT

RGB1 INPUT (PC INPUT)

RGB2 INPUT (DIGITAL RGB INPUT)

RS-232C INPUT

Note : All cables shown are not provided with the Monitor,

except : A D-sub 15 pin cable and DVI cable is supplied to connect the Monitor to a PC.

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AC INPUT

(8Ω)

EXTERNAL SPEAKER

( )( )

RGB1 OUTPUT

(PC OUTPUT)

AUDIO INPUT

RGB1 INPUT

(PC INPUT)

RGB2 INPUT

(DIGITAL RGB INPUT)

RS-232C INPUT (CONTROL/SERVICE)

( )( )

(8Ω)

EXTERNAL SPEAKER

AV1AV1

AC INPUT

(8Ω)

EXTERNAL SPEAKER

( )( )

COMPONENT(480i/480p)

(DVD INPUT)

AUDIO INPUT

VIDEO INPUT

AUDIO INPUT

RGB1 OUTPUT

(PC OUTPUT)

RGB1 INPUT

(PC INPUT)

RGB2 INPUT

(DIGITAL RGB INPUT)

RS-232C INPUT (CONTROL/SERVICE)

( )( )

S-VIDEO

(8Ω)

EXTERNAL SPEAKER

Y PBP

(MONO)

AUDIO

Socket Type

Scart Type

1 2 3 4 5

1. EXTERNAL SPEAKER (8 ohm output)

Connect this terminal to the optionally available speaker. *For further information, refer to ‘Speaker & Speaker stand’ manual.

2. POWER INPUT SOCKET

This Monitor operates on an AC mains supply, the voltage is as indicated as inside back cover of this manual. Never apply DC power to the Monitor.

3. VIDEO/S-VIDEO/COMPONENT(DVD INPUT)/AUDIO INPUT SOCKETS

EURO SCART SOCKET

Note : The interface board(AP-50EA40/41) is not

equipped on MT/MZ-50PZ41/43 series models. Contact your dealer for buying this optional item.

4. RGB1 OUTPUT(PC OUTPUT)/AUDIO IN SOCKETS

You can watch the RGB1 signal in other monitor by connecting RGB1 OUTPUT(PC OUTPUT) to other monitor’s PC input jack.

Note : When you watch after connecting with other monitor, a. When you select RGB1 or RGB2 for main picture, you can watch AV1, AV2 or S-Video for sub picture. b. When you select AV1, AV2 or S-Video for main picture, You can watch main picture’s viewing.

RGB1 INPUT(PC INPUT)/RGB2 INPUT(DIGITAL RGB INPUT) IN SOCKETS

Connect the monitor output socket of the PERSONAL COMPUTER to this socket.

5. RS-232C INPUT(CONTROL/SERVICE) SOCKET

Connect it to the RS-232C socket on the PC.

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- When using the remote control aim it at the remote control sensor of the Monitor.

1 2 3

4 5 6

7 8

POWER

SLEEP INPUT SELECT

PSM SSM

ARC PIP ARC

PIP

TWIN PICTURE

SWAP

MENU MUTE

VOL

POWER STOP

PLAY FF

REC

REW

P/STILL

WIN.SIZE

WIN.POSITION

ZOOM +

ZOOM -

SPLIT ZOOM

VOL

SUB INPUT

1. POWER

switches the set on from standby or off to standby.

2. SLEEP

sets the sleep timer.

3. PSM (Picture Status Memory)

recalls your preferred picture setting.

4. ARC (Aspect Ratio Control)

changes the picture format.

5. PIP

switches the sub picture on or off.

6. SWAP

alternates between main and sub picture.

7. MENU Button

selects a menu.

DD/ EE

selects a menu item.

FF/ GG

(Volume Down/Up)

adjusts the volume. adjusts menu settings.

displays the current mode.

9. NUMBER BUTTONS

10. VCR BUTTONS

control a LG video cassette recorder.

11. WIN. SIZE

adjusts the sub picture size.

12. ZOOM-/ZOOM+

13. INPUT SELECT BUTTON

selects TV, AV or PC monitor mode.

14. SSM (Sound Status Memory)

recalls your preferred sound setting.

15. PIP ARC

changes the picture format of PIP.

16. TWIN PICTURE

17. SUB INPUT

selects the input mode for the sub picture.

18. MUTE Button

switches the sound on or off.

19. SPLIT ZOOM

enlarge the screen with regular ration.

20. WIN.POSITION

moves the sub picture to

DD/ EE

or FF/ GGdirection.

13 14 15 16 17 18

19 20

2 3 4 5 6 7

11 12

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D-sub 15 pin cable

AS mark

LG TV

Owner’s Manual

1.5V

Alkaline batteries

BNC-RCA adapter (optional)

DVI cable

Power cord

1 2 3

4 5 6

7 809

POWER

SLEEP INPUT SELECT

PSM SSM

ARC PIP ARC

PIP

TWIN PICTURE

SWAP

MENU MUTE

VOL

POWER STOP

PLAY FF

REC

REW

P/STILL

WIN.SIZE

WIN.POSITION

ZOOM +

ZOOM -

SPLIT ZOOM

VOL

SUB INPUT

Remote control handset

Simple monitor stand

Ceiling mounting bracket

- Optional extras can be changed or modified for quality improvement without any notification new optional extras can be

added.

- Contract your dealer for buying these items.

Accessories

Optional Extras

Tilt wall mounting bracket

Wall mounting bracket

Video cables

Desktop stand

Desktop Speaker stand

Speakers

PC audio cables

1. Application Object

These instructions are applied to all of the PDP monitor, RF02CA.

2. Notes

(1) Because this is not a hot chassis, it is not necessary to use

an isolation transformer. However, the use of isolation

transformer will help protect test instrument. (2) Adjustment must be done in the correct order. (3) The adjustment must be performed in the circumstance of

25±5°C of temperature and 65±10% of relative humidity if

there is no specific designation. (4) The input voltage of the receiver must keep 110~240V,

50/60Hz in adjusting. (5) The receiver must be operated for about 15 minutes prior

to the adjustment.

1) After receiving 100% white pattern(06CH), the receiver must be operate prior to adjustment. (Or white condition in HEAT-RUN mode)

2) Enter into HEAT-RUN mode

- Press the POWER ON KEY on R/C for adjustment.

- OSD display HEAT-RUN WHITE and screen display

100% full WHITE PATTERN.

[ Set is activated HEAT-RUN without signal generator in

this mode.

[ Single color pattern of HEAT-RUN mode uses to check

PANEL. (RED/BLUE/GREEN)

[Caution]

If you turn on a still screen more than 20 minutes

(Especially Digital pattern(13 CH), Cross Hatch Pattern), a afterimage may be occur in the black level part of the screen.

3. RGB Auto Cut-Off & MIN Bias Adjustment

(1) Input Full Back (0 Gray) signal which generated from

Pattern Generator into CVBS and RGB1 Input part.

(2) Press POWER ON KEY on R/C for adjustment and select

AUTO-CUT(Cut-off Auto Adjustment) (3) Press Vol. + key and operate TO SET (4) Screen adjustment starts with Full Black screen.

Original Window screen will be presented about 5-6

seconds later. And if there is a mark of OK OSD, then the

Auto Cut-off and Min-Bias adjustment will be completed. (5) Pass to the next MAX Bias Adjustment after Adjustment.

[ Replace PDP Module or Power Board, adjust certainly Power

PCB Assy Voltage.

4. MAX Bias Adjustment

(1) Input Full White (255 Gray) signal which generated from

Pattern Generator into CVBS and RGB1 Input part.

(2) Press POWER ON KEY on R/C for adjustment and select

MAX-BIAS (3) Press Vol. + key and operate TO SET (4) Original Full White screen will be presented about 1~2

seconds later. And if there is a mark of OK OSD, then the

Min-Bias adjustment will be completed. (5) After adjustment, press

key to save adjustment and

come out of the adjustment mode.

You can check whether circuit adjustment is operated well or not, as below.

(1) Display RGB1 to the Main picture, CVBS to the Sub

picture in the TWIN PICTURE. (2) To check the MIN-Bias, input Full Black (0 gray) signal into

CVBS and RGB1 input part at the same time in the Pattern

Generator. (3) To check the MAX-Bias, input Full White (255 gray) signal

into CVBS and RGB1 input part at the same time in the

Pattern Generator. (4) Compare Black Level with White Level by eyes. And if

there is no Level difference, the adjustment is completed

well.

Data value, which adjusted in the board, is valid until the VSC Board is dissued and must be protected. For the protection of data, Micom does not permit any more adjustment after completion.

In case of re-adjustment, operate First Value Setting.

Each PCB Assy must be checked by Check JIG Set before assembly. (Especially, be careful Power PCB Assy which can cause fatal Damage to PDP Module.)

5. POWER PCB Assy Voltage Adjustment

(Va, Vs Voltage Adjustment)

5-1 Test Equipment :D.M.M 1EA 5-2 Connection Diagram for Measuring

Refer to Fig 1.

5-3 Adjustment Method

(1) Va Adjustment

1) After receiving 100% white pattern, HEAT RUN.

2) Connect + terminal of D.M.M to Va pin of P805 and connect – terminal to GND pin of P805.

3) After turning the VR4, voltage of D.M.M adjustment as same as Va voltage which on label of panel Right/Top. (Deviation : ±0.5V)

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ADJUSTMENT INSTRUCTIONS

+ 18 hidden pages

LG MT-50PZ41VB, MT-50PZ41, MT-50PZ41VS, MT-50PZ43, MZ-50PZ43 Service Manual

Specifications and Main Features

Frequently Asked Questions

User Manual