LG 21FJ6 Schematic

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COLOR TV SERVICE MANUAL

CHASSIS: CP-079C

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

CONTENTS

Contents

Location & Function of control

Safety Precautions

Specifications

Adjustment

Block Diagram

R,G,B Section / Deflection Section

Audio AMP. Section

Exploded View

Exploded View Parts List

Replacement Parts List

Schematic Diagram

Location and function of controls

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 previous page.

1. POWER

switches the set from On to standby or standby to On.

2. NUMBER BUTTONS

switches the set On from standby or directly select a Programme number.

3. MENU

selects a menu.

14 12

4. EYE / (option)

POWER MUTE

5. / (Programme Up/Down)

(Volume Up/Down)

OK accepts your selection or displays the current mode.

6. Q. VIEW

Q-VIEWARC/* LIST

XDP/*

MM/*

7. PSM (Picture Status Memory)

8. XDP/*

9. MUTE

10. TV/AV

11. LIST

12. SLEEP

13. ARC/* (option)

PSM TV/AV

VOL VOL

EYE/*

FAVOURITE

SLEEP

switches the eye function On or Off.

selects a programme or a menu item. switches the set On from standby.

adjusts the volume. adjusts menu settings.

returns to the previously viewed programme.

recalls your preferred picture setting.

Select excellent Digital picture.

switches the sound On or Off.

selects TV or AV mode. clears the menu / text from the screen. switches the set On from Standby.

displays the programme table. press LIST key again to clear the LIST table from the screen.

sets the sleep timer.

change picture format (Normal/Zoom).

14. FAVOURITE pressing each time this button will select a stored favourite programme.

15. MM / * (option)

select music mode.

COLOURED BUTTONS : When Menu is On some of these buttons are used for programme edit.

Remarks : 1. Some keys in remote can be non-functional, these keys are used in other models.

# Remote Design / Aesthetic may vary from model to model.

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 XRADIATION, Shock, Fire, or other Hazards. Do not modify the original design without permission of manufacturer.

General Guidance

An Isolation 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 l0mm 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:

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.

Before returning the receiver to the customer,

always perform an AC leakage current check on the exposed metallic parts of the cabinet, such as antennas, terminals, etc., to be sure the set is safe to operate without damage of electrical shock.

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 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 antenna terminals, phone jacks, etc.

If the exposed metallic part has a return path to the chassis, the measured resistance should be between 1MW and 5.2MW.

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.

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 .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.

Leakage Current Hot Check circuit

AC Volt - meter

To Instrument's exposed METALLIC PARTS

1.5 Kohm10W

0.15uF

Good Earth Ground such as WATER PIPE, CONDUIT etc.

SERVICING PRECAUTIONS

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.

c. 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.

9. 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 500º F to 600º 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. (500º F

to 600º 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 (500º F

to 600º F)

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

component lead the solder melts.

c. OuIckly 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 suction type 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.

SPECIFICATIONS

Note : Specification and others are subject to change without notice for improvement.

 Video input system:

PAL-B/G, D/K, I/I

SECAM -B/G, D/K,L/L** NTSC M ** NTSC 4.43**

 Intermediate Frequency (Unit : Mhz)

VISION IF : 38.9MHz

35.32MHz(3.58) : NTSC-M

COLOR IF : 34.47MHz(4.43)

VIF-4.25000 MHz

( )

V I F-4.40625MHz**

: SECAM**

 Tuning range

SOUND IF : 33.4MHz (B/G)

 Power requirement : 110 240V, 50/60Hz  Power consumption :65W  STAND-BY : <7W

32.9MHz (I/I)

32.4MHz (D/K)

34.4MHz (M)

∼

Band

B/G

D/K

VHF-Low Ch2-4 Ch1-5

For TV

I/I

NTSC

For CATV

S1'-S3', S1

S2-S10,

VHF-High

Ch5-12

Ch6-12

Ch2-13

Hyper

UHF

 Tuning system : Feature :Auto programme /Manual programme

FVS Auto Sleep 100 Programme memory (option) PSM (Picture Status Memory) 200 Programme memory(W/0 TXT) Programme Editing

 Antenna input impedance : VHF/UHF 75 ohm, unbalanced XDP  OSD (On Screen Display) : EASY_MENU  Voice coil impedance : 8 ohm

 Sound output :

7W (MONO)

Ch4-13

Chl4-69 Ch21-69

Auto Volume Level Favourite Program

S11-S20

S21-S41

 External connection : AV IN, AV OUT  External In/Output

Audio-In:O.5Vrms±3dB, over 10Kohm Audio-Out:0.5Vrms±3dBb,below 1Kohm

Video-In/Out:1Vp-p±3d8, 75ohm

** For Export model.

DISASSEMBLY INSTRUCTIONS

Important note

This set is disconnected from the power supply through the converter. transformer. An isolating transformer is necessary for service operations on the primary side of the converter transformer.

Back Cabinet Removal

Removal the screws residing on the back cabinet and carefully separate the back cabinet from the front cabinet cabinet. (Fig. 2-1).

CPT Removal

1. Pull out the CPT board from the CPT neck.

2. Place the front cabinet on soft material not to mar the front surface or damage control knobs.

3. Remove 4 screws securing the picture tube mounting brackets to the front cabinet.

4. Carefully separate CPT from the front cabinet.

Chassis Assy Removal

Grasp both side of Frame and pull it backward smoothly.

PICTURE TUBE HANDLING CAUTION

Due to high vacuum and large surface area of picture tube, great care must be exercised when handling picture tube. Always lift picture tube by grasping it firmly around faceplate. NEVER LIFT TUBE BY ITS NECK! The picture tube must not be scratched or subjected to excessive pressure as fracture of glass may result in an implosion of considerable violence which can cause personal injury or property damage.

Remove Screws

CPT

board

Main PCB

ADJUSTMENT

 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. The adjustment must be done by the correct appliances.

But this is changeable in view of productivity.

5. Unless otherwise noted, set the line voltage to

110~240Vac ± 10%, 50/60Hz.

6. The adjustment of TV should be performed after

warming up for 20 minutes.

SVC3

FMWS 2 MONO 1 DSG 1 AGN 0 AVL 1 BPB 0 AVLE 1 AMLOW 0 BPB2 1 FF1 0 MAXVOL 100 DCXO 1 BGDM 0 PLL.SEL 1

 Test Equipment required

1 . Multi meter (volt meter)

2. Oscilloscope

3. 10:1 PROBE

OPT1

4. Color Analyzer

INCH 0

 CDL Data Adjustment(LINE SVC-0)

1) Press the SVC button to get into the SVC-0 Mode.

2) Press the Channel UP/DOWN button to select CDLl2.

3) Press the Volume UP/DOWN button until the CDL data is the same as the Table below.

14" SLIM

CDL Data 07 Remark SLIM

SYS 1 200PR 1 CH-AU 0 SND 0 S/AV 1

4) Press the OK button to memorize the data.

= OPTION Data Adjustment(OPTION-l,OPTION-2)

1) Press OK buttons on both TV set and Remote

Controller at the same time to get into SVC mode.

2) Press the Yellow button several times to find OPTION data.

3) Input the correspond OPTION data referring to Table

OPT2

VOL 1 H-DEV 1 MM 1

below with the numeric buttons.

4) Press the OK button to memorize the data.

EYE 0 DEG 0

Table 1. Function

IK 1

SVC1 AGC 27 WR 32 WG 32 WB 32 BLO-R 32 BLO-G 32 BLO-B 32 CDL 7 L-DLY 8

00.B 15

SVC2

V SLOP 27 VA 34 VS 33 HL 34 SL 26 EW WI 0 EW PA 0 EW UP 0 EW LO 0 EW TR 0 H PAR 0 H BOW 0 V-LIN 0 V SCROL 0 V ZOOM 0 WBR 0 WBF 0 V -SLY 0

DVD 0

OPT3

HOTEL 0 XD/TU 1 TURBO 1 X WAVE 0 TR/IC 1

OPT4

OSD LANG 1 0: ENG 1: HINDI BLUE BACK 1 0: DISABLE 1: ENABLE

SVC4

WS 0 BKS 1 BSD 1 DSK 0 COR 0 PF 3 RPO 0 RPA 2 PWL 0 IFOFF 9 CHSE 1 ACL 0 BLOC 5 TEXT-V 40 TEXT-H 5 VGAURD 0 TER 1 GAM 1

0: W/O EW 1: W EW 0: 4 SYSTEM (BG/DK/I)

1: 3 SYSTEM (BG/DK/I) 0: OFF 1: ON 0: OFF

1: ON 0: MONO 0: AV-STEREO 0: 2AV 1: 1AV

0:LOW CARVE

1: HIGH CARVE 0: SOUND HIGH DEVIATION OFF

1: SOUND HIGH DEVIATION ON 0: W/O MUSIC MODE 1: W MUSIC MODE

0: W/O EYE 1: WITH EYE

0: W/O DEGAUSS 1: WITH DEGAUSS

0: IK OFF 1: IK ON 0: W/O COMP

1: WITH COMP

0:HOTEL MODE OFF 1: HOTEL MODE ON

0: TURBO PICTURE ON 1: XDP 0: W/O TURBO PICTURE 1: WITH TURBO PICTURE

0: W/O X WAVE 1: WITH X WAVE

0: IC BASE 1: TRANSISTOR BASE

AGC Adjustment (SERVICE 1)

Test Point :AGC TP (C102) Adjust :Remote Controller

1) Connect RF signal (70dBt0.2d8) and turn on the TV.

Standard adjustment Channel

-EU 05 Ch. (frf= 175.25MHz)

2) Press the OK buttons on TV set and Remote Controller

at the same time to get into SVC-0 mode.

3) In SVC-0 option, AGCTO is meant for AGC.

4) Press the Volume UP/DOWN button until the AGC

Voltage is the same as the Table below.

5) Press the OK button to memorize the data.

Tuner P/N 6700MF0018B Marker LG Innotek(TBS TUNER) AGC Voltage 2.4 ± 0.05V

FOCUS Adjustment

Test Point : Observing Display Adjust : Focus Volume of FBT

1 )Tune the TV set to receive a PAL OSCH.

2) Adjust the Focus Volume of FBT for best focus.

Screen voltage Adjustment

Test Point : Rk ( Red cathode of CPT board) Adjust : Screen volume of FBT

1)Connect the probe of oscilloscope to the RK (Red

Cathode) of CPT Board.

2)Set the oscilloscope to 50V/div and 20Us/div and after

putting GND line upon the lowest grid line of the scope by pressing GND button, enter into DC mode.

3) Tune the TV set to receive a PAL-BG O5GH.

4) Adjust Screen Volume of FBT so that the waveform is

the same as below figure (DC 100V).

Black level 100Vp-p

White level GND for dc

140Vp_p

leve

Horizornal FIyBack Time

W h i t e

White Balance Adjustment.(LINE SVC-0)

NOTE : This adjustment should be performed after screen

voltage adjustment.

1)Tune the TV set to receive an 100% white pattern.

2)Press OK buttons on TV set and remote controller at the same time to get into SVC mode.

3) Use the CH CH Key to chose adjustment item.

4) Use the VOL VOL Key to change item data.

5) Adjustment.

a)Make the picture luminance 4.5 changing the

" CONTRAST" and "BRIGHTNESS".

b)Adjust X data of low light with BLO-R and Y data with

BLO-B.

c)Adjust X dada of High light RG and Y data with BG. d) Repeat steps b~c until both low & high light hare same

readings as shown below.

L X- Data Y-Data

Low Light 255 260 High Light 260 265

Status Initial Data Remark

RG 32 GG 32

BG 32 BLO-R 32 BLO-G 32 BLO-B 32

6) Press the OK button to memorize the data.

 Deflection Data Adjustment (Line SVC-1 )

NOTE: To enter SVC mode, press "OK" buttons on both TV set

and the Remote control at the same time.

1. Preparation for Deflection Adjustment

1 ) At SVC mode, press the "IN- START" key.

And then, deflection data adjustment OSD (SVC1 mode) will be displayed.

2) Tune the TV set to receive a PAL 05 CH and set the ARC mode is standard.

2. Deflection Initial Setup Data

Status 14" SLIM

VSLOP 27

VA 34 VS 33 HS 34 SC 25

3. Deflection Adjustment Procedure

VSLOP (Vertical Slope)

Adjust so that the boundary line between upper and lower half is in accord with geometric horizontal center of the CPT.

VA (Vertical Amplitude)

Adjust so that the circle of a digital circle pattern may be located within the effective screen of the CPT.

SC (Vertical "S" Correction)

Adjust so that all distance between each horizontal lines are to be the same.

VS (Vertical Shift)

Adjust so that the horizontal center line of a digital circle pattern is in accord with geometric horizontal center of the CPT.

HS (Horizontal Shift)

Adjust so that the vertical center line of a digital circle pattern is i n accord with geometric vertical center of the CPT.

Press the OK button to memorize the data.

PURITY & CONVERGENCE ADJUSTMENT

Caution:

Convergence and Purity have been factory aligned. Do not attempt to tamper with these alignments.

However, the effects of adjacent receiver components, or replacement of picture tube or deffection yoke may require the need to readjust purity any convergence.

DEFLECTION YPKE

PURITY%CONVERGENCE MAGNET ASSEMBLY

6-POLE

X-AXISYOKE MAGNET POSITIONING (L/R PURITY)

RUBBER WEDGES

PURITY MAGNET

4-POLE

GLASS CLOTH TAPE

5. Reconnect the internal degaussing coil.

6. Position the beam bender locking rings at the 9 o'clock position and the other three pairs of tabs (2,4 and 6 pole magnets) at the 12 o'clock position.

6-POLE MAGNETS

4-POLE

CONVERGENCE MAGNET ASSEMBLY

PURITY MAGNET(2-POLE)

 Purity Adjustment

This procedure DOES NOT apply to bonded yoke and picture tube assemblies.

The instrument should be at room temperature (60 degress F or above) for six (6) hours and be operating at low beam current (dark background) for approximately 20 to 30 minutes before performing purity adjustments.

CAUTION: Do not remove any trim magnets that may be attached

to the bell of the picture tube.

1. Remove the AC power and disconnect the internal degaussing coil.

2. Remove the yoke from the neck of the picture tube.

3. If the yoke has the tape version beam bender, remove it and replace it with a adjustable type beam bender (follow the instructions provided with the new beam bender)

4. Replace the yoke on the picture tube neck, temporarily remove the three (3) rubber wedges from the bell of the picture tube and then slide the yoke completely forward.

7. Perform the following steps, in the order given, to prepare the receiver for the purity adjustment procedure.

a. Face the receiver in the "magnetic north" direction. b. Externally dsgauss the receiver screen with the television

power turned off.

c. Turn the television on for approximately 10 seconds to perform

internal degaussing and then turn the TV off.

d. Unplug the internal degaussing coil. This allows the thermistor

to cool down while you are performing the purity adjustment. DO NOT MOVE THE RECEIVER FROM ITS "MAGNETIC NORTH" POSITION.

e. Turn the receiver on and obtain a red raster by increasing the

red bias control (CW) and decreasing the bias controls for the remaining two colors (CCW).

f. Attach two round magnets on the picture tube screen at 3

o'clock and 9 o'clock positions, approximately one (1 ) inch from the edge of the mask (use double-sided tape).

1.ADJUST YOKE Z-AXIS FIRST TO GET EQUAL BLUE COLOR CIRCLES

MAGNETS

1.ADJUST BEAM BENDER 2 POLE MAGNET TO GET FOUR EQUAL COLOR CIRCLES

RED

8. Referring to above, perform the following two steps: a. Adjust the yoke Z-axis to obtain equal blue circles. b. Adjust the appropriate beam bender tabs to obtain correct purity

(four equal circles).

9. After correct purity is set, tighten the yoke clamp screw and remove the two screen magnets.

10. Remove the AC power and rotate the receiver 180 degrees (facing "magnetic south").

11. Reconnect the internal degaussing coil.

12. Turn the receiver on for 10 seconds (make sure the receiver came on) to perform internal degaussing, and then turn the receiver off.

13. Unplug the internal degaussing coil.

14. Turn on the receiver and check the purity by holding one (1) round magnet at the 3 o'clock and a second round magnet at 9 o'clock position. If purity is not satisfactory, repeat steps 8 through 14.

15. Turn off the receiver and reconnect the internal degaussing coil.&

 Convergence Adjustment

Caution: This procedure DOES NOT apply to bonded yoke and

picture tube assemblies. Do not use screen magnets during this adjustment

procedure. Use of screen magnets will cause an incorrect display.

1. Remove AC power and disconnect the internal degaussing coil.

2. Apply AC Power and set the brightness to the Picture Reset condition. Set the Color control to minimum.

3. Make a horizontal line.

4. Adjust the Red, Green and Blue Bias controls to get a dim white line.

RED

6. Reconnect the internal degaussing coil and apply AC power.

7. Turn he receiver on for 10 seconds to perform internal degaussing and then turn the receiver off again.

8. Unplug the internal degaussing-coil.

9. Turn on the receiver, connect a signal generator to the VHF antenna terminal and apply a crosshatch signal.

Caution: During the convergence adjustment procedure, be very

careful not to disturb the purity adjustment tabs are accidentally move, purity should be confirmed before proceeding with the convergence adjustments.

Note: Make sure the focus is set correctly on this instrument

before proceeding with the following adjustment.

10. Converge the red and blue vertical lines to the green vertical line

at the center of the screen by performing the following steps (below TABLE).

a. Carefully rotate both tabs of the 4-pole ring magnet

simultaneously in opposite directions from the 12 o'clock position to converge the red and blue vertical lines.

b. Carefully rotate both tabs of the 6-pole ring magnet

simultaneously in opposite directions form the 12 o'clock position to converge the red and blue (now purple) vertical lines with the green vertical line.

11. Converge the red and blue horizontal with the green line at the

center of the screen by performing the following steps. (below TABLE)

a. Carefully rotate both tabs of the 4-pole ring magnet

simultaneously in the same direction (keep the spacing between the two tabs the same) to converge the red and blue horizontal lines.

b. Carefully rotate both tabs of the 6-pole ring magnet

simultaneously in same direction (keep the spacing between the two tabs the same) to converge the red and blue (nowpurple) horizontal lines with the green horizontal line.

c. Secure the tabs previsouly adjusted by locking them in

place with the locking tabs on the beam bender.

5. Restore the screen by removing the horizontal line.

RING PAIRS

ROTATION DIRECTION OF BOTH TABS

MOVEMENT OF RED AND BLUE BEAMS

POLE

UP/DOWN ROCKING OF THE YOKE CAUSES OPPOSITE ROTATION OF RED AND BLUE RASTERS

GREEN

OPPOSITE

SAME

OPPOSITE

SAME

B B

R R

LEFT/RIGHT ROCKING OF THE YOKE CAUSES OPPOSITE SIZE CHANGE OF THE RED AND BLUE RASTERS

ADJUSTMENT

VIEWING

AREA

GREEN

BLUE

RED

ER D

RED

BLUE

GREEN

B UE

GREEN

12. While watching the 6 o'clock positions on the screen, rock the front of the yoke in a vertical (up/down) direction to converge the red and blue vertical lines. (Fig upper left)

13. Temporarily place a rubber wedge at the 12 o'clock position to hold the vertical position or the yoke.

14. Check the 3 o'clock and 9 o'clock areas to confirm that the red and blue horizontal lines are converged.

If the lines are not converged, slightly offset the vertical tilt of the yoke (move the rubber wedge if necessary) to equally balance the convergence error of the horizontal tines at 3 o'clock and 9 o'clock and the vertical lines at 6 o'clock and 12 o'clock.

15. Place a 1.5 inch piece of glass tape over the rubber foot at the rear of the 12 o'clock wedge.

16. While watching the 6 o'clock and 12 o'clock areas of the screen, rock the front of the yoke in the horizontal (left to right) motion to converge the red and blue horizontal lines. (Fig. upper right)

ADJUSTMENT

VIEWING

AREA

RED

BLUE

GREEN

TV SCREEN

17. Temporarily place a rubber wedge at the 5 o'clock and 7 o'clock positions to hold the horizontal position of the yoke.

18. Check the 3 o'clock and 9 o' clock areas to confirm that the red and blue vertical lines are converged. If the lines are not converged, slightly offset the horizontal tilt of the yoke (move the temporary rubber wedges if necessary) to equally balance the convergence error of the horizontal lines at 6 o'clock and 12 o'clock and the vertical lines at 3 o'clock and 9 o'clock.

19. Using a round magnet confirm purity at the center, right and left sides and corners. See Purity Adjustment Procedure.

20. Reconfirm convergence and apply a 1.5 inch piece of glass tape over the rubber toot at the rear of the 5 o'clock and the 7 o'clock wedges.

L401

Option Part

IIC Bus Line

SMPS

TRANS

10.5V

Zener

Regulator

ST-5V

P02A

(Pre amp/LED)

IC804

IC04

(ST-3.3V REG)

ST-3.3V

EER3940

For SW

(9V

REG)

IC803

(5V REG)

V_DY

B+

4 1

(Vertical Amp)

IC301 TDA4863AJ

PWR

H_DY

Q401

Collector

2SC6090

FBT

14V

35 34

SCL/SDA

A OUT

200V

-14V

ABL

28V

IC02

EEPROM

AT24C16

CP79C BLOCK DIAGRAM

AV_Out (V,L)

KEY

A IN V OUT

IC501 UOC Top

62 63

V IN

Rear_AV AV IN (V, L)

(Front Local Key)

47~44

Ik,R/G/B OUT

EYE

SPK OUT

P902A

(To CPT B/D)

IC602 TDA2006

(Sound Amp MONO)

IF IN

12 13

VIF

SAW

Z111

SAW

Z111

33V

SDA

SCL

SDA

SCL

(((

SPK OUT

(

R,G,B SECTION

ABL CIRCUIT

IC 501

brightness

reduction

(2.5V)

contrast

reduction

(3.5V)

BEAM CURRENT

J517

C548

10uF/50V

D501 4148

R415

6.8K

R402

1.2K

RS/1/2W

R416

91K

RS/1/2W

B+

R406

C402

0.022UF 200V(M)

FBT T402

ABL

To protect the picture tube and FBT,the average beam current an d peak beam current may not to high.

The beam current limit information and High Voltage(H.V) tracking information are derived from

the H.V voltage winding of T401 (point A).

1. The contrast and brightness reduction of RGB is proportional to the voltage on the pin 48 of IC501.

2. As the beam current(slow),and H.V (fast) are changes, the voltage of point A is changed.

3. By the increase of beam current ,the point A voltage is decreased and this information is fed to pin 48 of IC501.

- Contrast reduction begins when V49 is below than 3.1V.

- By the more increasing of the beam current , the V48 decreased and eventually when this voltage is less than

1.8V the brightness reduction is started.

Deflection SECTION

HORIZONTAL DRIVE CIRCUIT

IC501

H-OUT

R555

R556

J546

H.Vcc

R404C403

Q401

C2331Y

ZD418

C402

Q402

R413

C404

T403 HDT

2SC6093

Q402

R401

i1(t1.t2)

i2(t2.t3)

i4(t4.t5)

FB401

i3(t3.t4)

C414

H-DY

C412

FBT

Winding

B+

110V

Primary

1. The H drive output is open collector and active low, I.e. the H-out TR should conduct during the low period of output.

2. Under normal operation condition the duty cycle of the

output pulse is 50%.

3. To ensure a smooth start/stop behavior of the horizontal

deflection and protect the H-out TR, there are 3 different condition of H-drive output.

During switch-on. The horizontal output starts with the double frequency (31KHz) and with duty of 75%(off),25%(on).

After about 50mSec of switch-on. The frequency is changed to normal value(15.625KHz) and duty cycle to 50%.

During switching-off.

Also the frequency is switched to the double value and

R.G.B drive is set to Max. and after 100mSec R.G.B

is set to Min. and 50mSec later the H drive is switch-off.

4. The H drive pulse from the MICOM (IC 501) horizontal drive circuit,to get sufficient base drive current for the high voltage switching TR(Q402).

is amplified by the

VB of Q402

Collector

Current of Q402

The Voltage

at H-DY

The current of resonant

Capacitor

(C414)

DAMP

current

Deflection

current of

H-DY

tr : retrace period

t1 t2t3t4 t5 t6

ts : scannig period

t1 : Q402 is switched on.

t1.t2

: Collector current of Q402 increases linearly.

i1 flows from C412 Which have been charged

at the end of first half of scan. i5 also flows, energy stored in the primary winding(.) ) of FBT.

t2 : Q402 is switched off abruptly.

t2.t3

: Reverse EMF of H-DY maintains i1 direction

and charges C414. Reverse EMF of the FBT primary occurs to maintain is direction.

t3 : Q402 is still off.

t3.t4

: C414 discharges through H-DY.

t4.t5

: H-DY attempts to maintain i3 direction.

Damping diode becomes forward biased and C412 is charged.

AUDIO AMP. SECTION

TDA2006

through R626, R608 [Input level adjust] and C622, [AC coupling].

- Audio signal from the PIN 58 of IC501 are applied to PIN1

CIRCUIT ANALYSIS

AUDIO IN

FEEDBACK

ROLE DESCRIPTION

MINIMUM EXTERNAL COMPONENTS

INTERNALLY FIXED GAIN

THERMAL OVERLOAD PROTECTION

TDA2006

8W MONO AMPLIFIER

WIDE SUPPLY VOLTAGE RANGE (12.30V)

•••••

FEATURES :

SHORT CIRCUIT PROTECTION

Pin descriptions of TDA7297

Pin NO

AUDIO OUT

SOUND GND

SGND

SOUND SVCC

OUT

SVCC

• Q621 is for muting audio in.

EXPLODED VIEW

P801

913

112

170

150

500

400

410

300

120

LOCATION

150

170

300 400 500 913

P801

EAK51682104

EAB42432101 61409C2010E

EAD52408203

ABJ72911401 ACQ73029201

EBT6071201

FAB30021401

EAD53594701

CPT ASSEMBLY, A34KVL420X 01 K 14 INCH ULTRA SLIM LPDI.

SPEAKER, MID-RANGE

Coil, Degaussing

CPT EARTH

Cover Assembly, 14SB2RB-AJ BACK COVER ASSEMBLY,

Chassis Assembly

Screw Assembly

POWER CORD,ISI 2000 (GROOMET 325)MM . BLACK

PART NO PART NOLOCATION

Resistors

C117 0RN3902F409 FR401 0RF0470K607 FR403 0RF0121H609 FR404 0RP0050H709 FR405 0RP0050H709 FR406 0RP0050H709 FR825 0RP0020J809 J154 0RD4300F609 J241 0RD7501F609 J246 0RD7501F609 J501 0RD1000F609 J609 0RD5601F609 L101 0RD0392F609 L207 0RD2200F609 L208 0RD0752F609 R1 0RD1301F609 R100 0RD0562F609 R101 0RD1000F609 R102 0RD3601F609 R103 0RD1201F609 R104 0RD0272F609 R105 0RD6800F609 R110 0RS2702H609 R120 0RD1003F609 R134 0RD1002F609 R16 0RD1001F609 R17 0RD1501F609 R178 0RD4701F609 R179 0RD1803F609 R18 0RD2001F609 R19 0RD4300F609 R2 0RD1001F609 R20 0RD3000F609 R205 0RD0752F609 R21 0RD2401F609 R303 0RN0471H609 R304 0RN0471H609 R305 0RD2400A609 R308 0RD6202F609 R309 0RD6202F609 R310 0RD0561A609 R311 0RD5601F609 R312 0RD5601F609 R313 0RD4702F609 R314 0RD4702F609 R401 0RD0332A609 R402 0RD1201F609 R403 0RD3300A609 R405 0RS8201K607 R406 0RS1001H609

LOCATION

R412 0RD7501A609 R413 0RD5600A609 R415 0RD6801F609 R416 0RS9102H609 R425 0RS1800K619 R441 0RD1002F609 R501 0RD4700F609 R502 0RD2200F609 R504 0RD3900F609 R507 0RD3902F609 R508 0RD3302F609 R511 0RD2200F609 R512 0RD2200F609 R513 0RD2200F609 R514 0RD1001F609 R520 0RD1202F609 R521 0RD8203F609 R522 0RD2200F609 R523 0RD1000F609 R524 0RD4701F609 R525 0RD2200F609 R541 0RD4701F609 R549 0RD1202F609 R555 0RD1501F609 R556 0RD1000F609 R58 0RD4701F609 R621 0RD1503F609 R622 0RD6801F609 R623 0RD1003F609 R624 0RD1003F609 R625 0RD1003F609 R626 0RD5601F609 R627 0RD3902F609 R628 0RD0331H609 R67 0RD3301F609 R68 0RD1000F609 R69 0RD3301F609 R70 0RD1000F609 R802 0RKZVTA001K R803 0RD4701F609 R804 0RS3902K607 R805 0RS3902K607 R807 0RD2200A609 R808 0RD1501F609 R809 0RD1001F609 R810 0RD0332F609 R811 0RS0821K607 R812 0RD1003F609 R814 0RKZVTA001C R815 0RN9102G409 R816 0RN9102G409

PART NO PART NOLOCATION

LOCATION

Resistors

R82 0RD4701F609 R832 0RD4701F609 R835 0RD3001F609 R840 0RD0472F609 R841 0RD1001F609 R842 0RN2002F409 R843 0RD3902F609 R844 0RN4701F409 R845 0RD1001F609 R883 0RS1000K607 R901 0RD0472F609 R902 0RD1002F609 R904 0RD1002F609 R905 0RD1002F609 R906 0RD0472F609 R907 0RD0472F609 R908 0RD3300F609 R909 0RD3300F609 R910 0RD0472F609 R912 0RD0472F609 R915 0RD2204A609 R916 0RD3300F609 R917 0RS1802K607 R918 0RD2200F609 R919 0RS1802K607 R920 0RD3300F609 R921 0RD1501A609 R922 0RD2200F609 R923 0RS1802K607 R924 0RD2200F609 R925 0RD3300F609 R926 0RD3300F609 R927 0RD0472F609 R928 0RD1501A609 R929 0RD1501A609

Capacitors

C102 0CN1040K949 C103 0CE106DK618 C105 0CN1030F679 C107 0CN1030F679 C108 0CE226DF618 C110 0CE106DF618 C111 0CE476DF618 C112 0CN1020K519 C113 0CN1030F679 C115 0CN1030F679 C121 0CN1030F679

C207 0CN1030F679 C28 0CE107DD618 C303 0CK4710W515 C307 0CE107DJ618 C310 0CQ1041N409 C313 0CN2220F569 C314 0CQ2241N501 C315 0CN2220F569 C32 0CE476DD618 C40 0CE476DD618 C401 0CE475DR618 C402 181-009R C403 0CE106DF618 C404 0CQ1521N509 C408 0CE225DP618 C413 0CK1010W515 C414 181-015G C415 0CK4710W515 C416 181-009R C417 181-091W C419 0CE227CH638 C420 0CE227CH638 C421 0CK4710W515 C503 0CE476DF618 C504 0CQ1041N409 C506 0CE106DF618 C508 0CN1020K519 C511 181-301C C516 0CN1040K949 C517 0CE107DF618 C518 0CQ2242K439 C519 0CE105DK618 C520 0CQ6821N509 C521 0CE107DD618 C522 181-007C C523 0CE106DF618 C524 0CN1030F679 C525 0CN1030F679 C528 0CN1030F679 C537 0CE106DF618 C547 0CN1010K519 C548 0CE106DK618 C552 181-007C C554 0CN1030F679 C555 0CE476DF618 C561 0CE105DK618 C562 181-007C C563 0CQ6831N509 C564 0CE227DD618 C601 0CE107DD618 C602 0CQ1041N409 C613 0CE107DJ618

PART NO

LOCATION

PART NOLOCATION

Capacitors

C621 0CN1010K519 C622 0CE225DK618 C623 0CE336BK618 C624 0CE107DJ618 C625 0CQ1041N509 C626 0CE226DK618 C802 0CQZVBK002C C804 0CK10202515 C805 0CK10202515 C807 181-033R C809 0CE105DK618 C810 0CE336DK618 C813 181-033S C815 0CK8210K515 C816 0CE107CP618 C817 181-007C C818 0CQ2231N509 C819 0CK1520K515 C820 0CE476DD618 C821 0CK1520W515 C826 0CE228BF618 C828 0CE476DD618 C831 0CE227DJ618 C833 0CE107DD618 C843 181-120K C847 0CE105BR618 C850 0CE477DF618 C853 0CE107DH618 C902 0CE475DR618 C903 0CN3310K519 C904 0CN5610K519 C905 0CN5610K519 C906 0CK12202510

Diodes

D177 0DD414809ED D301 0DD060009AC D302 0DD400509AA D402 0DD060009AC D405 0DD060009AC D501 0DD414809ED D801 0DRDC00014Q D802 0DRDC00014J D803 0DRDC00014J D813 0DRDC00014G D826 0DRDC00014F D834 0DRDC00014F D901 0DRDC00014R D902 0DD414809ED D903 0DD414809ED D904 0DD414809ED DB801 0DRTW00131A ZD05 0DZ910009BD ZD06 0DZ910009BD ZD07 0DZ910009BD ZD08 0DZ910009BD ZD102 0DZ330009DF ZD401 0DZ510009BF ZD418 0DD414809ED ZD503 0DZ820009AH ZD511 0DZ910009BD ZD512 0DZ910009BD ZD513 0DZ910009BD ZD514 0DZ820009AH ZD802 0DZ510009BF ZD851 0DZ910009BD

PART NO

LOCATION

Transistors IC

PART NOLOCATION

Q10 0TR319809AA Q101 0TR319709AB Q401 0TR233109AA Q502 0TR198009BA Q621 0TR534309AA Q801 0TR534309AA Q813 0TR102009AB Q901 0TR233009CA Q902 0TR421009CC Q903 0TR233009CA Q904 0TR233009CA Q905 0TR421009CC Q906 0TR233009CA Q907 0TR233009CA Q908 0TR233009CA Q909 0TR421009CC

IC02 0IAL241600B IC301 0IPMGPH002A IC501 EAN57863702 IC601 0ISG200600A IC801 0IPMGSK016A IC802 0IPRPKD003A IC803 0IKE780500Q IC805 0IMCRAU004A IC806 0IMCRKE002B Q840 0IMCRFA007A

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Specifications and Main Features

Frequently Asked Questions

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