LG PF-43A20 Schematic

COLOR TV SERVICE MANUAL

CAUTION

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

CHASSIS : MP-87B

MODEL : PF-43A20

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CONTENTS

Contents .......................................................................................................... 2

Safety Precautions ..........................................................................................3

Servicing Precautions .................................................................................... 4

Specifications ................................................................................................. 6

Control Descriptions ...................................................................................... 8

Alignment/Test Point Location Guide...........................................................11

Adjustment......................................................................................................14

Troubleshooting.............................................................................................19

Component Location Guide.........................................................................26

Printed Circuit Board.....................................................................................27

Block Diagram................................................................................................34

Wiring Diagram...............................................................................................36

Exploded View .............................................................................................. 38

Exploded View Parts List...............................................................................39

Replacement Parts List ................................................................................ 40

SVC. Sheet .........................................................................................................

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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 TV receiver 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.

X-RAY Radiation

Warning:

To determine the presence of high voltage, use an accurate high impedance HV meter.

Adjust brightness, color, contrast controls to minimum. Measure the high voltage. The meter reading should indicate

23.5

¡ 1.5KV: 14-19 inch, 26 ¡ 1.5KV: 19-21 inch,

29.0 ¡ 1.5KV: 25-29 inch, 30.0 ¡ 1.5KV: 32 inch If the meter indication is out of tolerance, immediate service and correction is required to prevent the possibility of premature component failure.

Insulation Resistance Testing

Examine the area surrounding the repaired location for damage or deterioration, Observe that screws, parts and wires have been returned to original positions. Afterwards, perform the following tests and confirm the specified values in order to verity compliance with safety standards.

Requirements of the Electricity regulations 1997 and AS/NZS3760 : 1996 All products that are serviced must have a safety test carried out in accordance with AS/NZS 3760 : 1996.

This equipment is double insulated so the following test should be carried out.

Testing Equipment Required :

An insulation resistance meter with the following characteristics.

a) A measuring circuit isolated from earth b) Nominal measuring voltage 500V DC c) Accuracy Class 5 or better (Class 5 = accuracy of 5%)

Insulation resistance test. During this test the power switch must in the "ON" position. For the purpose of this test, small exposed metal parts such as nameplates, screws or rivets which are fixed or attached to non-conductive material in such a manner that they cannot become live, even in the event of a failure of internal insulation, are not required to be tested. Confirm that the insulation resistance between the power plug prongs and externally exposed parts of the unit (metal case, bottom cover, RF terminals, antenna terminals, video and audio output and input terminals, microphone jacks, earphone jacks, oxtension speaker sockets, etc) has a minimum resistance of 1M§ .

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 the same type tube as specified in the Replacement Parts List.

VIDEO

AUDIO

75Ω

OUT

LLEEGGEENNDD :: ¤ Any switch to be "ON"

during tests

¤Ł Test active and neutral to

exposed metal parts

Insulation resistance

meter

IMPORTANT SAFETY NOTICE

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CAUTION: Before servicing receivers covered by this service manual and its supplements and addenda, read and follow the

SAFETY PRECAUTIONS

on page 3 of this publication.

NOTE:

If unforeseen circumstances create conflict between the following servicing precautions and any of the safety precautions on page 3 of this publication, always follow the safety precautions. Remember: Safety First.

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 receiver assembly.

b. Disconnecting or reconnecting any receiver electrical plug

or other electrical connection.

Connecting a test substitute in parallel with an electrolytic capacitor in the receiver. CAUTION: A wrong part substitution or incorrect polarity installation 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 in 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.

Use with this receiver only the test fixtures specified in this service manual.

CAUTION: Do not connect the test fixture ground strap to any heatsink in this receiver.

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 fieldeffect

transistors and semicounductor "chip" components. The following techniques should be used to help reduce the incidence of component damage caused by static by static electricity.

1. Immediately before handling any semiconductor component or semiconductor-equipped assembly, drain off any electostatic 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 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 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 solder removal device. Some solder removal devices not classified as "anti-static" can generate electrical charges sufficent to demage ES devices.

5. Do not use freon-propelled chemicals. These can generate electrical charges sufficient to damage ES devices.

6. Do not remove a repalcement 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 ieads 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 harmless motion such as the bruching together of your clothes fabric or the lifting of your foot from a carpeted floor can generate static electricity sufficient to damage an ES device.)

General Soldering Guidelines

1. Use a grounded-tip, low-wattage soldering iron and appropriate tip size and shape that will maintan tip temperature within the range or 500¡£F to 600¡£F.

2. Use an appropriate gauge of RMA resin-core solder composed of 60 parts tin/40 parts lead.

3. Keep the soldering iron tip clean and well tinned.

4. Thorohly clean the surfaces to be soldered. Use a mall wirebristle (0.5 inch, or 1.25cm) brush with a metal handle. Do not use freon-propelled spray-on cleaners.

5. Use the following unsoldering technique a. Allow the soldering iron tip to reach normal temperature.

(500¡£F to 600¡£F) b. Heat the component lead until the solder melts. c. Quickly draw the melted solder with an anti-static,

suction-type solder removal device or with solder braid.

CAUTION: Work quickly to avoid overheating the

circuiboard printed foil.

6. Use the following soldering technique. a. Allow the soldering iron tip to reach a normal

temperature (500¡£F to 600¡£F)

b. First, hold the soldering iron tip and solder the strand

against the component lead until the solder melts.

SERVICING PRECAUTIONS

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c. Qulckly 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.

IC 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 the 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 in parapraphs 5 and 6 above.

Removal

1. 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.

2. Draw away the melted solder with an anti-static suctiontype solder removal device (or with solder braid) before removing the IC.

Replacement

1. Carefully insert the replacement IC in the circuit boare.

2. Carefully bend each IC lead against the circuit foil pad and solder it.

3. 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

1. Remove the defective transistor by clipping its leads as close as possible to the component body.

2. Bend into a "U" shape the end of each of three leads remaining on the circuit board.

3. Bend into a "U" shape the replacement transistor leads.

4. Connect the replacement transistor leads to the corresponding leads extending from the 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

1. Heat and remove all solder from around the transistor leads.

2. Remove the heatsink mounting screw (if so equipped).

3. Carefully remove the transistor from the heat sink of the circuit board.

4. Insert new transistor in the circuit board.

5. Solder each transistor lead, and clip off excess lead.

6. Replace heatsink.

Diode Removal/Replacement

1. Remove defective diode by clipping its leads as close as possible to diode body.

2. Bend the two remaining leads perpendicula y to the circuit board.

3. Observing diode polarity, wrap each lead of the new diode around the corresponding lead on the circuit board.

4. Securely crimp each connection and solder it.

5. 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 the 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).

2. carefully scratch away the solder resist and acrylic coating (if used) from the end of the remaining copper pattern.

3. Bend a small "U" in one end of a small gauge jumper wire and carefully crimp it around the IC pin. Solder the IC connection.

4. Route the jumper wire along the path of the out-away copper pattern and let it overlap the previously scraped end of the good copper pattern. Solder the overlapped area and clip off any excess jumper wire.

At Other Connections

Use the following technique to repair the defective copper pattern at connections other than IC Pins. This technique involoves the installation of a jumper wire on the component side of the circuit board.

1. Remove the defective copper pattern with a sharp knife. Remove at least 1/4 inch of copper, to ensure that a hazardous condition will not exist if the jumper wire opens.

2. Trace along the copper pattern from both sides of the pattern break and locate the nearest component that is directly connected to the affected copper pattern.

3. Connect insulated 20-gauge jumper wire from the lead of the nearest component on one side of the pattern break to the lead of the nearest component on the other side. Carefully crimp and solder the connections. CAUTION: Be sure the insulated jumper wire is dressed so the it does not touch components or sharp edges.

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SPECIFICATIONS

NOTE : Specifications and others are subject to change without notice for improvement.

¡ Video input system:

Multi 26 System (Refer to Table 1)

¡ Intermediate Frequency

Vision IF : 38.0MHz Color IF : 33.57MHz ¡ SECAM : 38.0-4.25MHz

34.42MHz(M) 38.0-4.40625MHz

Sound IF : 32.5MHz(B/G)

32.0MHz(I)

31.5MHz(D/K,K1)

33.5MHz(M)

¡ Tuning range

¡ OSD (On Screen Display):

Menu Method

¡ Antenna input impedance: VHF/UHF 75ohm, Unbalanced

¡ Voice coil impedance : 8 ohm

¡ External connections :

S-VIDEO (Super Video) A/V in : 1 pair S-VIDEO (Super Video) Scart(Full) A/V in : 1 pair A/V out : 1 pair

¡ Power requirements :

100-270 Vac, 50/60HZ

¡ Power consumption :

210 Wmax.

¡ Tuning system :

VS (Voltage Synthesizer) 100 Program Memory

¡ Sound output :

25 W max. X 2 way: (4 speaker) Dual / Stereo : A2, NICAM

¡ Local button :

Menu, OK, TV/AV, POWER Volume up(+), down(-) Program up(+), down(-)

¡ Function :

Auto Program Manual Program Auto Sleep ON/OFF TIMER

CATV/Hyper band Teletext (TOP/FLOF/LIST) PIP (Picture In Picture)

Child Lock :

In the Lock On state the TV can only be operated by the remote controller. If any button on the front panel is pressed, "CHILD LOCK ON" is displayed on the screen but the button's function is not performed. To cancel of this mode, select lock off with menu button on remote controller only.

¡ Features

Picture quality improvement circuit

- YNR (Luminance Noise Reduction)

- Picture Outline Compensation

Band

VHF-Low

VHF-High

UHF

PAL/SECAM-B/G

For TV

Ch 2-4

Ch 5-12

Ch 21-69

For CATV

S1’-S3’, S1

S2-S10

S11-S20

S21-S41

Hyper

Front

Rear

Video in/out

Audio in (2 way)

Audio out (2 way)

R. G. B in

Specifications

1Vp-p¡ 3dB, 75ohm

0.5Vrms¡ 3dB, over 10Kohm

0.5Vrms¡ 3dB, below 1Kohm

0.7Vp-p¡ 3dB

(

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Table 1 : Receiving System (26 System)

Receiving System

PPAALL--BB

PPAALL--GG

PPAALL--II

PPAALL--DD

PPAALL--KK

SSEECCAAMM--BB

SSEECCAAMM--GG

SSEECCAAMM--DD

SSEECCAAMM--KK

SSEECCAAMM--KK11

NNTTSSCC--MM

NTSC 4.43/5.5MHZ

NTSC 4.43/6.0MHZ

NTSC 4.43/6.5MHZ

SECAM-I (6.0MHZ)

SECAM-L (Video In)

NTSC 3.58/4.5MHZ/50HZ

PAL 5.5MHZ/60HZ

PAL 6.0MHZ/60HZ

PAL 6.5MHZ/60HZ

SECAM 5.5MHZ/60HZ

SECAM 6.0MHZ/60HZ

SECAM 6.5MHZ/60HZ

NTSC 3.58/5.5MHZ

NTSC 3.58/6.0MHZ

NTSC 3.58/6.5MHZ

Receiving Channel

VVHHFF BBaanndd PAL/SECAM-B

:: 22--1122

PAL/SECAM-D

:: 11--1122

SECAM-K1

:: 22--99

NTSC-M (US)

:: 22--1133

NTSC-M (JAPAN)

:: 11--1122

UUHHFF BBaanndd PAL/SECAM-G

:: 2211--6699

PAL-I

:: 2211--6699

SECAM-K

:: 2211--6699

PAL-K

:: 1133--5566

NTSC-M (US)

:: 1144--7788

NTSC-M (JAPAN)

:: 1133--6622

Function

Reception of broadcast and playback for Video Tape Recorder

Play-back for special Video Tape Recorder

Play-back for special Video tape/Video disk player

Play-back for special Video Tape Recorder

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CONTROLS DESCRIPTION

All the functions can be controlled with the remote control handset. Some functions can also be adjusted with the buttons on the front panel of the set.

Remote control handset

Before you use the remote control handset, please install the batteries. See the next page.

1. POWER

switches the set on from standby or off to standby.

2. MUTE

switches the sound on or off.

3. NUMBER BUTTONS

switch the set on from standby or directly select a number.

4. PIP BUTTONS (option) PIP

switches the sub picture on or off.

PR+/-

selects a programme for the sub picture.

SWAP

alternates between main and sub picture.

INPUT

selects the input mode for the sub picture.

SIZE

adjusts the sub picture size.

STILL

freezes motion of the sub picture.

POSITION

relocates the sub picture in clockwise direction.

9/4 PIP

switches on or off the programme scan mode through 9 or 4 sub pictures.

5. PSM (Picture Status Memory)

recalls your preferred picture setting.

6. SSM (Sound Status Memory)

recalls your preferred sound setting.

7. VCR BUTTONS (option)

control a LG video cassette recorder.

POWER

MUTE

1 2 3 I/II

4 5 6 PSM

7 8 9 TV/AV

PIP 0 TEXT MENU

PSM

PR- PR+ SWAP INPUT

SSM DUAL LIST

SIZE STILL

START

QSR

LENGTH SP/LP ON/OFF

CH+ REW PLAY FF

CH- P/STILL STOP REC

POSITION

PIP

9/4 PIP

VOL

T X T

V C R

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8. DUAL

selects the language during dual language broadcast. selects mono sound during stereo broadcasts.

9. TV/AV

selects TV or AV mode.

10. MENU

selects a menu.

11. ¡ª/¡ (Programme Up/Down) switches the set on from standby. selects a programme or a menu item.

¢‚/¢” (Volume Down/Up) adjusts the volume. adjusts menu settings.

accepts your selection or displays the current mode.

12. LIST

display the programme table.

13. TELETEXT BUTTONS (option)

These buttons are used for teletext. For further details, see the 'Teletext' section.

Note : In teletext mode, the PR+/-, SWAP and INPUT buttons are used for teletext function.

POWER

MUTE

1 2 3 I/II

4 5 6 PSM

7 8 9 TV/AV

PIP 0 TEXT MENU

PSM

PR- PR+ SWAP INPUT

SSM DUAL LIST

SIZE STILL

START

QSR

LENGTH SP/LP ON/OFF

CH+ REW PLAY FF

CH- P/STILL STOP REC

POSITION

PIP

9/4 PIP

VOL

T X T

V C R

8 5

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1. MAIN POWER (on the side of TV)

switches the set on or off.

2. AUDIO/VIDEO(or S-VIDEO) IN SOCKETS (AV 2)

Connect the audio/video(or S-video) out sockets of external equipment to these sockets.

3. TV/AV

selects TV or AV mode.

4. MENU

selects a menu.

5. OK

accepts your selection or displays the current mode.

6. ¢‚/¢” (Volume Down/Up)

adjusts the volume. adjusts menu settings.

7. ¡ª/¡ (Programme Up/Down) switches the set on from standby. selects a programme or a menu item.

8. POWER

switches the set on from standby or off to standby.

9. POWER / STANDBY INDICATOR

illuminates when the set is in standby mode. dims when the set is switched on.

10. REMOTE CONTROL SENSOR

S-VIDEO

TV/AV

OK VOL PR

VIDEO

L/MONO

AUDIO R

AV 2

5 8

Front panel

* CASTERS (on the bottom)

turn and move the set easily.

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ALIGNMENT/TEST POINT LOCATION GUIDE

SIGNAL Board (Component side)

DEFLECTION Board (Component side)

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IF (Component side)

- 13 -

PIP (Component side)

CPT Board (Component side)

VR902R

VR902G

VR902B

§ Safety Precautions

1. It is safe to adjust after using insulating transformer between the power supply line and chassis input to prevent the risk of electric shock and protect the instrument.

2. Never disconnect leads while the TV receiver is on.

3. Don't short any portion of circuits while power is on.

4. Don't operate the TV with a non-moving picture for any more than 10 minutes as damage may occur to the phosphor on the CRT.

5. The adjustment must be done by the appropriate appliances and the correct step.

6. Unless otherwise noted, set the line voltage to 220V ¡ 10%, 50Hz.

§ Test Equipment required

1. VIF sweep generator

2. Color bar/cross-hatch pattern generator

3. DC power supply

4. Digital multi-meter

5. Color analyzer

NOTE :

: PIP Board

¡ Main VCO (Voltage Controlled Oscillator)

Adjustment

1) Turn on DC power supply.

Adjust LI6 so that the waveform of Oscilloscope becomes

2.6V DC.

¡ PIP VCO (Voltage Controlled Oscillator)

Adjustment

1) Turn on DC power supply.

Adjust Video Detector Coil ( LP8 ) so that a waveform on Alignment Scope is the same as below Fig.2.

¡ AFT (Auto Fine Tuning) Adjustment

1) Turn on DC power supply.

2) Adjust IF AFT coil (LP5 ) so that 38.0MHz (Vc) point may be centered as Fig.3.

Test Point : TP22

Adjust : LP8

ADJUSTMENT INSTRUCTIONS

Test Point : TP3

Adjust : LI6

- 14 -

Preparation for VCO & AFT Adjustment

1. Connect the measuring equipment to the TV as shown in Fig.1.

2. Set RF output level of Sweep S.G (Signal Generator) to 90dBuV.

3. Set Alignment Scope, Volts/Div to 100mV (VCO) or 1V(AFT), AC/DC switch to AC, Line/Ext switch to Ext.

Fig.1 : Connection Diagram of Equipment for

VCO & AFT Adjustment.

2.6V

GND

A B C D E F G

A : 30.0MHz B : 31.5MHz C : 32.84MHz D : 36.8MHz E : 38.0MHz F : 39.5MHz G : 40.25MHz

Fig.2 : VCO waveform on Alignment Scope

Test Point : TP23

Adjust : LP5

Fig.3: AFT waveform on Alignment Scope

DC POWER

SUPPLY

12 0.1V

3.3K 1K

4.7K

To TP2/ TP21

TP24

VCO : ON AFT : OFF

SWEEP S.G.

with Marker

(VP-8800G)

Alignment

Scope

0.01µF

(VCO)

(AFT)

To TP1/ TP20

To TP3/ TP22

TP23

A: 36.8MHz B: 38.0MHz

Test Point : J104/ J106

Adjust : VRI1 / VRP1

¡ RF AGC (Auto Gain Control) Adjustment

The RF AGC control (VRI1/ VRP1 ) was aligned at the time of manufacture for optimum performance over a wide range conditions. Readjust of VRI1/ VRP1 should not be necessary unless unusual local conditions exist, such as:

1) Channel interference in a CATV system.

2) Picture bending and/or color beats, which are unusually due to excessive RF signal input when the receiver is too close to a transmitting tower or when the receiver is connected to an antenna distribution system where the RF signal has been amplified. In this case, the input signal should be attenuated(with pad or filter) to a satisfactory level.

3) Picture noise caused by "broadcast noise" or weak signal. If the broadcast is "clean" and the RF signal is at least 1mV(60dBuV), the picture will be noise free in any area.

Adjusting the VRI1/ VRP1 (RF AGC) control to one end of rotation will usually cause a relatively poor signal to noise ratio; Adjusting to the other end of rotation will usually cause a degradation of over load capabilities resulting in color beats or adjacent channel reference. For best results, adjust the VRI1/ VRP1 control while performing on all over local channels, or the voltage at J150/ J151 will be 6.0¡ 0.1Vdc in RF level 60¡ 1dBuV.

¡ High Voltage Stabilization Adjustment

1) Tune the TV set to receive a digital pattern.

2) Set contrast to 100%, brightness and color to 50% respectively.

3) Adjust VR402 on the deflection board so that the DC voltmeter may be read 4.0¡ 0.1Vdc.

¡ Vertical/Horizontal Size Adjustment

1) Tune the TV set to receive a digital pattern.

2) Set contrast to 100%, brightness and color to 50% respectively.

3) Adjust VR301 on the deflection board so that the circle of the digital pattern may be located within the effective screen on the TV screen.

4) Adjust VR401 on the deflection board so that the circle of the digital pattern looks like exact circle.

¡ Cut-off Adjustment

NOTE : This adjustment should be performed after

warming up for 15 minutes at least.

1) Set VR902R, 902G, 902B on CRT Boards to the mechanical center position.

2) Tune the TV set to receive white pattern of PAL standard signal.

3) Press OK button on Control Board continuously and INPUT(blue) button on remote controller for obtaining a horizontal line on the middle of TV screen.

4) Turn VR902R, 902G, 902B counterclockwise and set it to the minimum position.

5) Turn VR902R, 902G, 902B clockwise slowly to appear a horizontal line.

- 15 -

Test Point : J67 (on Deflection Board)

Adjust : VR402

Test Point : Observing Display

Adjust : VR301 (Vertical Size)

VR401 (Horizontal Size)

Test Point : Observing Display

Adjust : VR902R, 902G, 902B (Cut-off)

- 16 -

Caution :

These adjustments have been factory aligned. Do not attempt to temper with these alignments. However, the effects of adjacent receiver components, or replacement of picture tube or deflection yoke may require the need to readjust these adjustments.

¡ Raster Slant Adjustment

1. Peliminary steps

1) The lens focus and electrical focus must be provisional alignment.

2) Tune the TV set to receive a digital pattern.

Press the buttons of Remote Controller for adjustment (SVC

¡ ¡ 5¡ OK¡ ) to reset the convergence.

2. Adjustment

1) Set only green to be appeared on the screen.

2) Carefully rotate the DY of the green CRT so that the slant of raster become the following figure.

3) Set two color (R or B and G) to be appeared on the screen.

4) Set the slant of Red or Blue correspond to the green.

Note :

¡ Raster Position Adjustment

1. Preliminary steps

1) The lens focus and electrical focus must be provisional alignment.

2) This adjustment should be performed after the raster slant, the horizontal and the vertical adjustment.

3) Tune the TV set to receive a digital pattern.

4) The convergence must be corrected. Press the buttons of Remote Controller for adjustment (SVC ¡ ¡ 5¡ OK¡ ) to reset the convergence.

2. Adjustment

1) Turn the centering magnet of Green CRT so that the center of video signal correspond to geometrical center of screen.

2) Tune the TV set to receive cross hatch signal and turn the centering magnet of Red & Blue so that the center of cross hatch pattern correspond to Green center.

Lens and Electrical Focus Adjustment

1. Preliminary steps

1) The electrical focus, the raster slant and position must be provisional alignment.

2) This adjustment should be performed after warming up for 30 minutes and in the dark room.

3) Tune the TV set cross hatch pattern.

4) Screen the optional two lens with a cover so that the single color is appeared on the screen.

5) When turn the light the lens at front, chromatic aberration which appeared in bright line of cross-Hatch signal changed as below.

¡ After focus adjustment, fix screw about 12~ 17kg.cm.

2. G-lens Adjustment

1) Turn the lens until the chromatic aberration changed 'Blue' to 'Red point'.

Viewing the all screen, in no case of the chromatic aberration appeared slimly within 3.5 cross-Hatch of the picture center. At this time, in case that the red chromatic aberration's bright line isn't equal, adjust G-lens so that the red chromatic aberration is appeared more than previous time.

3) Switching the signal to digital pattern and operate adjustment minutely. At this time, adjust it by using the revolution pattern of circumferencial picture's small circle.

4) Adjust G-focus control volume of focus pack so that the external big circle's part appeared cleary.

5) Adjust accurately by repeat the upper control.

6) Especially, noting to the G-light because it influenced on picture's function.

3. R-lens Adjustment

1) Turn the lens until the chromatic aberration changed orange to scarlet.

2) Adjust the chromatic aberration so that it located center correctly.

3) Switching the signal to digital pattern and adjust it as same method of G-lens.

4) Adjust as same method of G-lens with Red focus control volume of focus pack.

RASTER SLANT/POSITION, FOCUS & CONVERGENCE ADJUSTMENT

Mechanical

center

1. Tighten the tighten iron after loose completely tighten iron which fixing DY when adjusting raster slant and set position.

2. Never control to the tighten iron which fixed, it's condition is not untied.

Lens

Red

Green

Blue

Change of chromatic aberration Orange ¤AScarlet Blue ¤ARed Purple ¤AGreen

CHROMATIC

ABERRATION

CROSS HATCH

SIGNAL

L ¡´ 2mm

- 17 -

4. Blue lens Adjustment

1) Turn the lens until the chromatic aberration changed purple to green which of 3.5 Cross-Hatch part from picture's center toward left.

2) Adjust the chromatic aberration become center of purple and green.

3) Turn the VR to clockwise so that the thickness of Bbright line thicker than G-bright line as much as times of

1.3 ¡ 0.2 after control method as same of G-focus by Bfocus VR of focus pack.

4) Remove lens cover after adjusting all lens (R.G.B) and receive cross hatch signal, observing condition of whole screen's condition.

¡ Convergence Adjustment

1. Preliminary steps

1) This adjustment should be performed after raster slant, raster position, horizontal and vertical adjustment.

2) This adjustment should be performed after warming up 30 minutes.

3) Tune the TV set cross-hatch pattern.

4) Adjust for both PAL(SECAM) and NTSC system.

5) Use the jig screen with the cross hatch pattern for each mode.

2. Convergence Key(Button)

1) Convergence Mode :

2) Phase Adjustment : 95

3) Pattern Position Adjustment : 94

4) Phase/Pattern Position Save : 92

5) Cursor Color Selection : TV/AV

6) Cursor Movement/Adjustment Selection : OK

7) Adjustment DATA Save : 91

¡ Mode Adjustment

1. Preliminary steps

Press the buttons SVC & of Remote Controller for adjustment to get into the convergence adjustment mode.

2. Phase Adjustment

1) Press the buttons 9 & 5 to get into the phase adjustment mode.

2) Horizontal Phase Adjustment. Press the volume ¢‚/¢”button and move the convex part to the middle of TV screen.

3) Vertical Phase Adjustment Press the channel ¡ª/¡ button and move the convex part to the middle of TV screen.

Press the OK button to escape from the adjustment.

3. Pattern Position Adjustment

Press the buttons 9 & 4 to get into the pattern movement mode. Press the volume ¢‚/¢”button & channel ¡ª/¡ button and move the cursor to the middle of TV screen.

4. Phase/Pattern Position Save

Press buttons 9 & 2 and OK.

5. Green Convergence Adjustment

1) Press TV/AV button and select the green cursor.

2) Press the volume ¢‚/¢”button & channel ¡ª/¡ button and adjust the green pattern & screen jig pattern.

3) If necessary, cover the R lens & B lens.

¡ Cursor flickers in the adjustment mode and stops in the

cursor position movement mode. Use OK button to toggle the cursor position movement mode and adjustment mode. Adjust and move outskirts from center.

Number is the order for adjustment position. Adjust anyone first for the same number.

The second mark

The horizontal center-line

The horizontal center

The vertical center

The horizontal center

The vertical center

8 6 5 4 5 6 8

7 5 3 2 3 5 7

6 4 2 1 2 4 6

7 5 3 2 3 5 7

8 6 5 4 5 6 8

6. Red Convergence Adjustment

1) Press TV/AV button and select the red cursor.

2) If necessary, cover B lens.

3) Adjust as same as the green convergence adjustment and coincide the red pattern with the green pattern.

7. Blue Convergence Adjustment

1) Press TV/AV button and select the blue cursor.

2) Adjust as same as the red convergence adjustment and coincide the blue pattern with the green pattern.

8. Adjustment DATA Save

Press buttons 9 & 1 and save adjustment DATA.

9. Press button to escape from the adjustment.

¡ White Balance Adjustment

1. Used Tools : Brightness meter (TOPCON BM-7)

2. Condition

1) It must be operated at a place of the darkroom.

2) This adjustment must be performed after focus adjustment finished.

3) Brightness meter must be at a place of 3[m] from the middle of optical screen.

4) Adjust focus of brightness meter to optical screen. And adjust the field angle. (1¡£)

3. Adjustment

1) Receive the white balance signal of 100%.

2) Select SVC Mode by SVC Remote Controller.

3) Adjust G-GN & B-GN and X=0.280 & Y=0.300. (Deviation :

¡ 0.005)

¡ Sub White Balance Adjustment

1) Press OK buttons on both of TV and Remote Controller at the same time to get into SVC mode.

2) Press the Yellow button to find a TABLE of below 3 tables.

3) Select a menu with channel up/down button and adjust the data with volume ¡ª/¡ button.

4) Press OK button to save the data.

5) Press TV/AV button to escape the SVC mode.

- 18 -

SVC 3 MODE

FM PRE NC PRE SC PRE SC VOL PH VOL

H-CEN

SBRIGHT

STINT

Rcut Gcut

Bcut G-GN B-GN

128

141 112

138

111

09 50 50

19 74 36 50 50

+ 41 hidden pages