Akira 21BM18 Schematic

FILE NO. SM-CTV-O-154

COLOR TELEVISION

SERVICE MANUAL

MODEL NO. 21BM18

CHASSIS NO. EX-1A1

Please read this manual carefully before service

TABLE OF CONTENTS

SPECIFICATIONS··················································································································1

SAFETY INSTRUCTIONS AND MAINTENANCE········································2

X-RAY RADIATION PRECAUTION ···································································································2

SAFETY PRECAUTION ····················································································································

PRODUCT SAFETY NOTICE············································································································

SAFETY SYMBOL DESCRIPTION ···································································································

MAINTENANCE·································································································································

2

3

3

4

ADJUSTMENTS······················································································································5

SET-UP ADJUSTMENTS···················································································································5

CIRCUIT ADJUSTMENTS·················································································································

8

STRUCTURE AND CHASSIS FUNCTION DESCRIPTION··············· 14

STRUCTURE BLOCK DIAGRAM··································································································· 14

BLOCK DIAGRAM FOR SUPPLY VOLTAGE SYSTEM·································································

CHASSIS DESCRIPTION···············································································································

15

16

SERVICE DATA

TECHNICAL DATA OF KEY ICS····································································································· 17

WAVEFORMS OF KEY POINTS····································································································

···················································································································· 17

35

SERVICE DATA OF KEY ICS ·········································································································

REPLACEMENT OF PARTS ··········································································································

APPENDIX

1. CIRCUIT DIAGRAMS

2. PRINTED CIRCUIT BOARD DIAGRAMS

3. FINAL WIRING DIAGRAMS

4. FINAL ASSEMBLY DIAGRAMS

37

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SERVICE MANUAL

SPECIFICATIONS

Model Number 21BM18

Color system

RF system

Sound system

VHF

Receiving

channel

Programs preset 236(0-235)

Antenna input

Picture tube (Approx.)

Effective screen dimensions
Audio output (THD≤7%)

Power source 110-240V ~, 50/60Hz

Weight (Approx.) 23kg

Dimensions
(W×H×D) (Approx.)

Rated power consumption 69W

Designs and specifications are subject to change without notice.

UHF

CATV

PAL4.43, SECAM, NTSC3.58, NTSC4.43

B/G, D/K ,I,M

C1～C12 (49.75-85.25MHz, 168.25-216.25MHz)

C13～C57 (471.25-863.25MHz)

Z1～Z7 (111-167MHz)

Z8～Z35 (223-447MHz)

75Ω(unbalanced)

406×305mm

3W+3W

585×461×485mm

1

SERVICE MANUAL

INSTRUCTIONS FOR SERVICE SAFETY AND MAINTENANCE

WARNING: BEFORE SERVICING THIS CHASSIS, READ THE “X-RA Y RA DIATION PRECAUTION”,

“

SAFETY PRECAUTION”AND “PRODUCT SAFETY NOTICE”INSTRUCTION BELOW.

X-RAY RADIATION PRECAUTION

1. The EHT must be checked every time the TV is serviced to ensure that the CRT does not emit

X-ray radiation as result of excessive EHT voltage. The maximum EHT voltage permissible in any

operating circumstances must not exceed the rated value. When checking the EHT, use the High

Voltage Check procedure in this manual using an accurate EHT voltmeter.

2. The only source of X-RAY radiation in this TV is the CRT. The TV minimizes X-RAY radiation, which

ensures safety during normal operation. To prevent X-ray radiation, the replacement CRT must be

identical to the original fitted as specified in the parts list.

3. Some components used in this TV have safety related characteristics preventing the CRT from

emitting X-ray radiation. For continued safety, replacement component should be made after

referring the PRODUCT SAFETY NOTICE below.

4. Service and adjustment of the TV may result in changes in the nominal EHT voltage of the CRT

anode. So ensure that the maximum EHT voltage does not exceed the rated value after service

and adjustment.

SAFETY PRECAUTION

WARNING: REFER SERVICING T O QUALIFIED SERVICE PERSONNEL ONLY.

1. The TV has a nominal working EHT voltage. Extreme caution should be exercised when working

on the TV with the back removed.

1.1 Do not attempt to service this TV if you are not conversant with the precautions and procedures for

working on high voltage equipment.

1.2 When handling or working on the CRT, always discharge the anode to the TV chassis before

removing the anode cap in case of electric shock.

1.3 The CRT, if broken, will violently expel glass fragments. Use shatterproof goggles and take extreme

care while handling.

1.4 Do not hold the CRT by the neck as this is a very dangerous practice.

2. It is essential that to maintain the safety of the customer all power cord forms be replaced exactly

as supplied from factory.

3. Voltage exists between the hot and cold ground when the TV is in operation. Install a suitable

isolating transformer of beyond rated overall power when servicing or connecting any test

equipment for the sake of safety.

4. When replacing ICs, use specific tools or a static-proof electric iron with small power (below 35W).

2

SERVICE MANUAL

5. Do not use a magnetized screwdriver when tightening or loosing the deflection yoke assembly to

avoid electronic gun magnetized and decrement in convergence of the CRT.

6. When remounting the TV chassis, ensure that all guard devices, such as nonmetal control buttons,

switch, insulating sleeve, shielding cover, isolating resistors and capacitors, are installed on the

original place.

7. Replace blown fuses within the TV with the fuse specified in the parts list.

8. When replacing wires or components to terminals or tags, wind the leads around the terminal

before soldering. When replacing safety components identified by the international hazard symbols

on the circuit diagram and parts list, it must be the company-approved type and must be mounted

as the original.

9. Keep wires away from high temperature components.

PRODUCT SAFETY NOTICE

CAUTION: FOR YOU PROTECTION, THE FOLLOWING PRODUCT SAFETY NOTICE SHOULD BE
READ CAREFULLY BEFORE OPERATING AND SERVICING THIS TV SET.

1. Many electrical and mechanical components in this chassis have special safety-related

characteristics. These characteristics are often passed unnoticed by a visual inspection and the

X-ray radiation protection afforded by them cannot necessarily be obtained by using replacements

rated at higher voltages or wattage, etc. Components which have these special safety

characteristics in this manual and its supplements are identified by the international hazard

symbols on the circuit diagram and parts list. Before replacing any of these components read the

parts list in this manual carefully. Substitute replacement components which do not have the same

safety characteristics as specified in the parts list may create X-ray radiation.

2. Do not slap or beat the cabinet or CRT, since this may result in fire or explosion.

3. Never allow the TV sharing a plug or socket with other large-power equipment. Doing so may result

in too large load, causing fire.

4. Do not allow anything to rest on or roll over the power cord. Protect the power cord from being

walked on, modified, cut or pinched, particularly at plugs.

5. Do not place any objects, especially heavy objects and lightings, on top of the TV set. Do not install

the TV near any heat sources such as radiators, heat registers, stove, or other apparatus that

produce heat.

6. Service personnel should observe the SAFETY INSTRUCTIONS in this manual during use and

servicing of this TV set. Otherwise, the resulted damage is not protected by the manufacturer.

SAFETY SYMBOL DESCRIPTION

The lightning symbol in the triangle tells you that the voltage inside this product may be

strong enough to cause an electric shock. Extreme caution should be exercised when

3

SERVICE MANUAL

working on the TV with the back removed.

This is an international hazard symbol, telling you that the components identified by the

symbol have special safety-related characteristics.

FDA

This symbol tells you that the critical components identified by the FDA marking have

special safety-related characteristics.

UL This symbol tells you that the critical components identified by the UL marking have

special safety-related characteristics.

C UL This symbol tells you that the critical components identified by the C-UL marking have

been evaluated to the UL and C-UL standards and have special safety-related

characteristics.

VDE

This symbol tells you that the critical components identified by the VDE marking have

special safety-related characteristics.

MAINTENANCE

1. Install the TV set on a stable and level surface. Do not place the set near or over a radiator or heat

register, or where it is exposed to direct sunlight.

2. Do not install the TV set in a place exposed to rain, water, excessive dust, mechanical vibrations or

impacts.

3. Allow enough space (at least 10cm) between the TV and wall or enclosures for proper ventilation.

4. Slots and openings in the cabinet should never be blocked by clothes or other objects.

5. Please power off the TV set and disconnect it from the wall immediately if any abnormal condition

are met, such as bad smell, belching smoke, sparkling, abnormal sound, no picture/sound/raster.

Hold the plug firmly when disconnecting the power cord.

6. Unplug the TV set from the wall outlet before cleaning or polishing it. Use a dry soft cloth for

cleaning the exterior of the TV set or CRT screen. Do not use liquid cleaners or aerosol cleaners.

4

SERVICE MANUAL

ADJUSTMENTS

SET-UP ADJUSTMENTS

The following adjustments should be made when a complete realignment is required or a new picture

tube is installed.

Perform the adjustments in the following order:

1. Color purity

2. Convergence

3. White balance

Notes:

① The purity/convergence magnet assembly and rubber wedges need mechanical positioning.
② For some picture tubes, purity/ convergence adjustments are not required.

1. Color Purity Adjustment

Preparation:

Before starting this adjustment, adjust the vertical sync, horizontal sync, vertical amplitude and

focus.

1.1 Face the TV set north or south.

1.2 Connect the power plug into the wall outlet and turn on the main power switch of the TV set.

1.3 Operate the TV for at least 15 minutes.

1.4 Degauss the TV set using a specific degaussing coil.

1.5 Set the brightness and contrast to maximum.

1.6 Counter clockwise rotate the R/B low brightness potentiometers to the end and rotate the green low

brightness potentiometer to center.

1.7 Receive green raster pattern signals.

1.8 Loosen the clamp screw holding the deflection yoke assembly and slide it forward or backward to

display a vertical green zone on the screen. Rotate and spread the tabs of the purity magnet

around the neck of the CRT until the green zone is located vertically at the center of the screen.

1.9 Slowly move the deflection yoke assembly forward or backward until a uniform green screen is

obtained.

1.10 Tighten the clamp screw of the assembly temporarily. Check purity of the red raster and blue raster

until purities of the three rasters meet the requirement.

5

SERVICE MANUAL

g

Adj

)

(

)

g

y

Deflection Coil

Dummy Wedge

Rubber Wedge

Glass Cloth Tapes

4-pole Magnet

Purity Magnet

Conver

ence Magnet Assembl

Purity/Convergence

net Module

Ma

6-pole Magnet

Deflection Yoke

Fig. 1

ust the Angle (Vertical Lines

Adjustment of Magnets

Fig. 2

Adhesive

Fixed

Rotate Two Tabs At the
Same Time

Horizontal Lines

2. Convergence Adjustment

Preparation:

Before attempting any convergence adjustment, the TV should be operated for at least 15 minutes.

2.1 Center convergence adjustment

2.1.1 Receive dot pattern.

2.1.2 Adjust the brightness/contrast controls to obtain a sharp picture.

2.1.3 Adjust two tabs of the 4-pole magnet to change the angle between them and red and blue

vertical lines are superimposed each other on the center of the screen.

2.1.4 Turn both tabs at the same time keeping the angle constant to superimpose red and blue

horizontal on the center of the screen.

2.1.5 Adjust two tabs of the 6-pole magnet to superimpose red/blue line and green line.

2.1.6 Remember red and blue movement. Repeat steps2.1.3～2..1.5 until optimal convergence is

6

SERVICE MANUAL

obtained.

2.2 Circumference convergence adjustment

2.2.1 Loosen the clamp screw holding the deflection yoke assembly and allow it tilting.

2.2.2 Temporarily put the first wedge between the picture tube and deflection yoke assembly. Move

front of the deflection yoke up or down to obtain better convergence in circumference. Push the

mounted wedge in to fix the yoke temporarily.

2.2.3 Put the second wedge into bottom.

2.2.4 Move front of the deflection yoke to the left or right to obtain better convergence in

circumference.

2.2.5 Fix the deflection yoke position and put the third wedge in either upper space. Fasten the

deflection yoke assembly on the picture tube.

2.2.6 Detach the temporarily mounted wedge and put it in either upper space. Fasten the deflection

yoke assembly on the picture tube.

2.2.7 After fastening the three wedges, recheck overall convergence and ensure to get optimal

convergence. Tighten the lamp screw holding the deflection yoke assembly.

BLU Red Red/BLU

BLU

Red

Red/BL

U

4-pole Magnet Movement 6-pole Magnet

Movement

Incline the Yoke up (or down) Incline the Yoke Right(or left)

Circumference Convergence by DEF Yoke

Fig. 3

3. White Balance Adjustment

Generally, white balance adjustment is made with professional equipment. It’s not practical to get

good white balance only through manual adjustment. For TVs with I

2

C bus control, change the bus

data to adjust white balance.

7

SERVICE MANUAL

CIRCUIT ADJUSTMENTS

Preparation:

Circuit adjustments should be made only after completion of set-up adjustments.

Circuit adjustments can be performed using the adjustable components inside the TV set. For TVs with

2

I

C bus control, first change the bus data.

1. Degaussing

A degaussing coil is built inside he TV set. Each time the TV is powered on, the degaussing coil will

automatically degauss the TV. If the TV is magnetized by external strong magnetic field, causing

color spot on the screen, use a specific degausser to demagnetize the TV in the following ways.

Otherwise, color distortion will be shown on the screen.

1.1 Power on the TV set and operate it for at least 15 minutes.

1.2 Receive red full-field pattern.

1.3 Power on the specific degausser and face it to the TV screen.

1.4 Turn on the degausser. Slowly move it around the screen and slowly take it away from the TV.

1.5 Repeat the above steps until the TV is degaussed completely.

2. Supply Voltage Adjustment

Caution: +B voltage has close relation to high voltag e. To prevent X-ray radiation, set +B voltage to
the rated voltage.

2.1 Make sure that the supply voltage is within the range of the rated value.

2.2 Connect a digital voltmeter to the +B voltage output terminal of the TV set. Power on the TV and set

the brightness and sub-brightness to minimum.

2.3 Regulate voltage adjustment components on the power PCB to make the voltmeter read 115±1V.

3. High Voltage Inspection

Caution: No high voltage adjustment components inside the chassis. Please perform high voltage
inspection in the following ways.

3.1 Connect a precise static high voltmeter to the second anode (inside the high voltage cap) of the

picture tube.

3.2 Plug in the supply socket (110-240V, AC, 50/60Hz) and turn on the TV. Set the brightness and contrast

to minimum (0μA).

3.3 The high voltage reading should be less than the EHT limitation.

3.4 Change the brightness from minimum to maximum, and ensure high voltage not beyond the

limitation in any case.

Nominal EHT voltage: 26.5±1.5KV

Limited EHT voltage: 27.5KV(For LG or Seg Hitachi CRT) or 29.5KV(For others)

4. Focus Adjustment

Caution: Dangerously high voltages are present inside the TV. Extreme caution should be
exercised when working on the TV with the back removed.

4.1 After removing the back cover, look for the FBT on the main PCB. There should be a FCB on the

FBT.

4.2 Power on the TV and preheat it for 15 min.

8

SERVICE MANUAL

4.3 Receive a normal TV signal. Rotate knob of the FCB until you get a sharp picture.

5. Safety Inspection

5.1 Inspection for insulation and voltage-resistant
Perform safety test for all naked metal of the TV. Supply high voltage of 3000V AC, 50Hz (limit
current of 10mA) between all naked metal and cold ground. Test every point for 3 min. and ensure
no arcing and sparking.

5.2 Requirements for insulation resistance
Measure resistance between naked metal of the TV and feed end of the power cord to be infinity
with a DC-500 high resistance meter and insulation resistance between the naked metal and
degaussing coil to be over 20MΩ.

6. DESIGN/SERVICE mode

6.1 To enter the USER SERVICE mode

Caution: The user service mode adjustment can be changed only when service personnel adjust
the whole set data during servicing. As the control data have dramatic effects on functions and
performance of the TV, service personnel should not tell user how to
enter the SERVICE mode to avoid improper data settings.

6.1.1 Set the volume to 0. Then press and hold the MUTE button on

the remote control, and press the MENU button on the TV to

S

VS 0-3F 25

xxxxxxxx

enter the SERVICE mode. (In this case, the S mode cannot be
stored in the EEPROM. To exit from the S mode, turn off the TV set. )

6.1.2 After entering the S mode, Red “S”is displayed on the upper center of the screen and MENU1

is default. Use the POS+/- buttons to highlight an adjustment and the VOL+/- buttons to adjust
it. The adjusted data are immediately output and stored in the EEPROM

6.2 Bus data in the S mode

Item Adjustment Description Remarks
CORE 03 Coring (for some CPU only)
0-IF 20 Sound adjustment setting (for some CPU only)
5PAR/6P
AR
5BOW/6
BOW

5HSH/6H
SH

5EWW/6
EWW
5EWP/6
EWP

1F Parallelogram correction (for large-screen only)

1F Curve correction (for large-screen only)

Set to the
optimal mode

Horizontal center in the TV mode for 50Hz/60Hz
For 50Hz, “5HSH” is displayed；for 60Hz, “6HSH”
is displayed.

1F East-West correction (for large-screen only)

1F

East-West parabola correction (for large-screen
only)

*

(continued)

9

SERVICE MANUAL

5UCR/6
UCR
5LCR/6L
CR
5EWT/6
EWT
5VSL/6V
SL
5VAM/6V
AM
5SCL/6S
CL

5VSH/6V
SH

5VOF/6V
OF

1F

1F

1F Trapezoidal correction (for large-screen only)

1F Vertical slope (for large-screen only) *

1F
Set to the

optimal mode
Set to the

optimal mode
Set to the

optimal mode

Upper corner parabola correction (for large-screen
only)
Lower corner parabola correction (for large-screen
only)

Vertical ampli t ude; For 50Hz, “5VAM” is displayed；
for 60Hz, “6VAM” is displayed.

S correction *
Vertical center in the TV mode for 50Hz/60Hz. For

50Hz, “5VSH” is displayed；for 60Hz, “6VSH” is
displayed.

OSD vertical center *

*

*

VX 19 Vertical zoom (for large-screen only)
RED 20 Red gun cutoff voltage *
GRN 20 Green gun cutoff voltage *
WPR 1F Red gun drive voltage *
WPG 1F Green gun drive voltage *
WPB 1F Blue gun drive voltage *
YDFP/Y
DFN

07 PAL brightness delay time/ NTSC brightness delay time

TOP 10-1F UOC AGC *

TV audio output power can be adjusted by means of
UOC audio output amplitude. Generally, UOC audio

VOL 2A

output amplitude is set to 26 for 21” models with stereo
output of 3W+3W; 2C for 21” models with stereo output

*

of 5W+5W; 24 for 14” models with mono output of
2WX2; 22 for 14” models with mono output of 1WX2.

IFFS

03（02）

PIF (02-38.9MHz, 03-38MHz)
HDOL 00-07 Cathode drive level (typical: 04-07)
AGC 03 IF ACG speed

VG2 brightness setting(VG2B): 3A for 21” models;

2E for 14” models;

VG2B 3A

Contrast Max. setting (MCON): 30 for 21” Malaysia

Matsushita or BMCC CRT with ferrite mask;

MCON: 30; VG2B: 30, HDOL: 04 for 21” Chunghwa

CRT

(continued)

10

01

SERVICE MANUAL

SBRI 1F Sub brightness
MBRI 30 Brightness Max.
SCON 20 Sub contrast
MCON 39 Contrast Max.
SCOL 32 Sub color
OP1 BF Option set byte 1 *
OP2 Option set byte 2 *

01

OP3 FF Option set byte 3 *
OP4 Option set byte 4 *

F6

OP5 76 Option set byte 5 *
OP6 3C Option set byte 6 *
INIT EEPROM initialization
VG2 Adjusting screen voltage with VG2
VSD Vertical output off
STS0/1/2 System status byte

Notes:

① The data marked with “*”have been adjusted in the MANUFACTURE mode. Take care when in

service and adjustment.

② To write in logo, use the ↓/↑buttons to highlight an adjustment and the ←/→ buttons to adjust.
③ The data sheet may differ dependent on different models.
④ The data sheet may differ dependent on different CRTs for the same model.

6.3 Option set

With remote control system software TDA935X, all options can be set in the SERVICE mode and
stored in EEPROM. Data related to picture, sound and geometric adjustment are also stored in
EEPROM.

Bit Item

Function Option Bit Setting

Description

Data
0 OP_HOTEL 1
1 OP_236 1
2 OP_NTSC NTSC color system options: 1: Yes, 0: No 1

OP1

3 OP_AV2

Two sets of AV inputs: 1: Two sets of separate AV inputs
0：Two sets of parallel AV inputs or one set of AV inputs

1/0
4 OP-SVSH S-Video terminal: 1: Yes, 0: No 1
5 OP-DVD DVD component input: 1: Yes 1
6 OP-RGB RGB input: 1: Yes, 0: No 1
7 OP-OSO 1

(continued)

11

OP2

SERVICE MANUAL

0 OP_AVL 1

AV RF output: 1: RF output (for models with SCART jack

1 OP_RFTOAV

except EX-1A)

0/1

0: Monitor output (for models with RCA jack)
2 OP_NOT_1 0
3 OP_NOT_2 0

Teletext language setting (OP-NOT-3/2/1):

1XX-English/Arabic

011-English/Farsi

010-English/Russian
4 OP_NOT_3

001-English/Ukrainian

0

000- English/Paneuro
5

OP_USER-LOG
O

0
6 OP_ON-BLACK 0

OP3

OP4

7 OP_FSL 0
0 OP_ENGLISH English 1
1 OP_FARSI Farsi or Czech 1
2 OP_ARABIC Arabic or Slovakian 1
3 OP_RUSSIAN Russian 1
4 OP_FRENCH French 1
5 OP_GERMAN German 1
6 OP_ITALY Italian, Indonesian or Hungarian 1
7 OP_SPANISH S panish, Malay or Croatian 1
0 OP_FMWS 0

1

OP_DIRECT_SW
ITCH_ON

1
2 OP_HCO 1

3 OP_LOGO 0
4 OP_SOUND_DK Sound system-D/K option setting 1
5 OP_SOUND_BG Sound system-B/G option setting 1
6 OP_SOUND_I Sound system-I option setting 1

OP5

7 OP_SOUND_M Sound system-M option setting 1

0 OP_TUNER 0

(continued)

12

SERVICE MANUAL

1

2

OP_AUTO_LAN
G0
OP_AUTO_LAN
G1

Outgoing language option setting:

(OP-AUTO-LANG2/1/0):

0

English (000)

Farsi (001)

0

Arabic (010)

Russian (011)
3

OP_AUTO_LAN
G2

French (100)

German (101)

0

Italian or Indonesian (110)

Spanish or Malay (111)
4 OP_FORF 1
5 OP_FORS

1

6 OP_AVON 1
7

OP_ONPOSITIO
N

0
0 OP_AUTOTEST Auto test when power-on (set to 0 typically) 0

1 OP_PSNS 0
2 OP_BSCREEN 1
3 OP_SECAM SECAM color system option: 1: Yes 1

OP6

4 OP_DFL 1
5 OP_SIF External SIF amplifier: 1: Yes, 0: No 1
6 OP_EXT_SIF0 1

Sound system options for external circuit

(OP-EXT-SIF1/0):

D/K: 00，B/G: 01，I: 10，M: 11.

1: Sets sound system of external SIF as the appropriate
7 OP_EXT_SIF1

one and also sets sound system in the course of auto

demo as the appropriate one

0: Changes sound system in the course of auto demo.

Notes:

① Do not change the data marked with “

0

” in “Data”column.

13

SERVICE MANUAL

Tuner

A101

IF Pre-

Amplifier

+

SAWF

Analog Switc h

HEF4053

Video

Amplifier

Formed of

Microcontroller and small signal processor

UOC

CH05T0102

EEPROM
AT24C08

Audio Prec essor

TDA7449

H.Drive

V.OUT

TDA8356J

Audio Amp lifier

TDA7057AQ

H.OUT

FBT

T402

Power Supply Circuit

STR-F6654 or

STR-G5653

+3.3V+5V-1

+15V

+115V

CRT

Audio/Video

Input/Output

Band 1,2

Vt,AGC

From

Antenna

IIC BUS

Audio
Input

R

L

Speaker

110-240V~,50/60Hz

VY01-VY09

G RB

R e m o t e

Remote

Sens or

HS 0038

Circui for

Bu tton s On

The TV

c o n t ro l

STRUCTURE AND CHASSIS FUNCTION DESCRIPTION

1. STRUCTURE BLOCK DIAGRAM

Fig.4 Structure Block Diagram for EX-1A1 Chassis Series

14

SERVICE MANUAL

Regulator

V115

N441

N442

Regulator

V871,

VD882

FBT

T400

VD491

+190V

VD451

+45V

VD461

+16V

VD471

To CRT RGB PCB

To A100,N401

To N401

+8V

+5V-2

To A100

VD891

+115V

To N600

VD881 +15V-H

VD871 +15-S

+5V-1

To H Ou t
EEPROM
R/C Input

+3.3V

To N100

Keyboard

Switch

Transformer

T804

Power Regulat ion
and Control Circuit
STR-G5653/F6654

Bridge Rectifying

Filter

VD803~VD806

C802,C807

Line Filter

L801,C801,

C802

110-240V~,50/60Hz

Feedback Circuit

N801

Error Signal

To A100,

N100,

N650

2. BLOCK DIAGRAM FOR SUPPLY VOLT-AGE SYSTEM

Fig .5 Block Diagram for EX-1A1 Supply Voltage System

15

SERVICE MANUAL

3. CHASSIS DESCRIPTION

1). General Description

EX-1A1 chassis series are applied in 21BM18 respectively which uses mainly Philips’

advanced UOC-ultimate chip TDA935X/6X/8X and I

microcontroller and small signal processor, the TDA935X/6X/8X series feature high-integration,

high-performance-to-price ratio and high-reliability and advanced functions with fewer external

components, which provide much convenience for manufacturing and technical service.

2). The EX-1A1chassis series mainly use the following ICs and assemblies.

Table 1 Key ICs and Assemblies

Serial

Position Type Function Description

No.

1 N100 TDA935X/6X/8X

Microcontroller and small signal processor(UOC)

(CH05T0102)

2 N200 AT24C08 EEPROM

3 N650 TDA7449 Audio processor

4 N401 TDA8356/N6 Vertical scan output stage circuit

5 N600 TDA7057AQ Sound power amplifier

6 N861 STR-G5653/F6654 Power supply circuit

7 N402 HEF4053 Analog switch

8 A100 TDQ-5B6M Tuner

2

C-bus controlled IC. With combination of

16

SERVICE MANUAL

SERVICE DATA

1. KEY ICS TECHNICAL DATA

1.1 Microcontroller and small signal processor TDA935X/6X/8X

The super chips TDA935X/6X/8X are good in pins compatibility. Differences among them are shown

as follows.

TDA9351（48K） PAL/NTSC/SECAM+1 PAGE TELETEST
TDA9350（48K） PAL/NTSC+1 PAGE TELETEST
TDA9361（64K） PAL/NTSC/SECAM+10 PAGE TELETEST
TDA9360（64K） PAL/NTSC+10 PAGE TELETEST
TDA9380（32K） PAL/NTSC
TDA9387（32K） NTSC

TDA935X/6X/8X PS/N2 series TV signal processor-Teletext decoder with embedded

　-Controller

1) General Descripion

The various versions of theTDA935X/6X/8X PS/N2 series combine the functions of a TV signal
processor together with a 　-Controller and US Closed Caption decoder. Most versions have a

Teletext decoder on board. The Teletext decoder has an internal RAM memory for 1or 10 page text.
The ICs are intended to be used in economy television receivers with 90 and 110 picture tubes.

The ICs have supply voltages of 8 V and 3.3 V and they are mounted in S-DIP envelope with 64

pins.

The features are given in the following feature list. The differences between the various ICs are

given in the table on page 4.

2) Features
TV-signal processor

● Multi-standard vision IF circuit with alignment-free PLL demodulator

● Internal (switchable) time-constant for the IF-AGC circuit

● A choice can be made between versions with mono intercarrier sound FM demodulator and

versions with QSS IF amplifier.

● The mono intercarrier sound versions have a selective FM-PLL demodulator which can be switched

to the different FM sound frequencies (4.5/5.5/6.0/6.5 MHz).

The quality of this system is such that the external band-pass filters can be omitted.

● Source selection between ‘internal’ CVBS and external CVBS or Y/C signals

● Integrated chrominance trap circuit

● Integrated luminance delay line with adjustable delay time

● Picture improvement features with peaking (with variable centre frequency and positive/negative

overshoot ratio) and black stretching

● Integrated chroma band-pass filter with switchable centre frequency

● Only one reference (12 MHz) crystal required for the

● -Controller, Teletext- and the colour decoder

17

SERVICE MANUAL

● PAL/NTSC or multi-standard colour decoder with automatic search system

● Internal base-band delay line

● RGB control circuit with ‘Continuous Cathode Calibration’, white point and black level offset

adjustment so that the colour temperature of the dark and the light parts of the screen can be

chosen independently.

● Linear RGB or YUV input with fast blanking for external RGB/YUV sources. The Text/OSD signals

are internally supplied from the 　-Controller/Teletext decoder

● Contrast reduction possibility during mixed-mode of OSD and Text signals

● Horizontal synchronization with two control loops and alignment-free horizontal oscillator

● Vertical count-down circuit

● Vertical driver optimized for DC-coupled vertical output stages

● Horizontal and vertical geometry processing

● Horizontal and vertical zoom function for 16 : 9 applications

● Horizontal parallelogram and bow correction for large screen picture tubes

● Low-power start-up of the horizontal drive circuit

TV signal processor-Teletext decoder with embedded 　-Controller TDA935X/6X/8X PS/N2
series

● -Controller

● 80C51 　-controller core standard instruction set and timing

● 1 s machine cycle　

● 16 - 128Kx8-bit late programmed ROM

● 3 - 12Kx8-bit DATA RAM (shared between Display, Acquisition and Auxiliary Ram)

● Interrupt controller for individual enable/disable with two level priority

● Two 16-bit Timer/Counter registers

● One 16 bit Timer with 8-bit Pre-scaler

● WatchDog timer

● Auxiliary RAM page pointer

● 16-bit Data pointer

● Stand-by, Idle and Power Down (PD) mode

● 14 bits PWM for Voltage Synthesis Tuning

● 8-bit A/D converter

● 4 pins which can be programmed as general I/O pin, ADC input or PWM (6-bit) output

Data Capture

● Text memory for 0, 1 or 10 pages

● In the 10 page versions inventory of transmitted Teletext pages stored in the Transmitted Page

Table (TPT) and Subtitle Page Table (SPT)

● Data Capture for US Closed Caption

● Data Capture for 525/625 line WST, VPS (PDC system A) and Wide Screen Signalling (WSS) bit

decoding

● Automatic selection between 525 WST/625 WST

● Automatic selection between 625 WST/VPS on line 16 of VBI

● Real-time capture and decoding for WST Teletext in Hardware, to enable optimized 　-processor

throughput

18

SERVICE MANUAL

● Automatic detection of FASTEXT transmission

● Real-time packet 26 engine in Hardware for processing accented, G2 and G3 characters

● Signal quality detector for video and WST/VPS data types

● Comprehensive teletext language coverage

● Full Field and Vertical Blanking Interval (VBI) data capture of WST data

Display

● Teletext and Enhanced OSD modes

● Features of level 1.5 WST and US Close Caption

● Serial and Parallel Display Attributes

● Single/Double/Quadruple Width and Height for characters

● Scrolling of display region

● Variable flash rate controlled by software

● Enhanced display features including overlining, underlining and italics

● Soft colours using CLUT with 4096 colour palette

● Globally selectable scan lines per row (9/10/13/16) and character matrix [12x10, 12x13, 12x16

(VxH)]

● Fringing (Shadow) selectable from N-S-E-W direction

● Fringe colour selectable

● Meshing of defined area

● Contrast reduction of defined area

● Cursor

● Special Graphics Characters with two planes, allowing four colours per character

● 32 software redefinable On-Screen display characters

● 4 WST Character sets (G0/G2) in single device (e.g. Latin, Cyrillic, Greek, Arabic)

● G1 Mosaic graphics, Limited G3 Line drawing characters

● WST Character sets and Closed Caption Character set in single device

Functional Difference Between The Various IC Versions
IC Version (TDA) 9350 9351 9352 9353 9360 9361 9362 9363 93 64 93 65 9366 9367 9380 9 381 9 382
9383 9384 9385 9386 9387 9388 9389

3) Block Diagram

19

SERVICE MANUAL

g

g

r

3) Block Diagram

ram for TDA935×/6×8×PS/N2 with Mono Intercarrier Sound Demodulato

.6 Block Dia
Fi

20

SERVICE MANUAL

Fig.7 Block Diagram for TDA935×/6×8×PS/N2 with QSS IF Sound Channel

21

SERVICE MANUAL

4) pinning
SYMBOL PIN DESCRIPTION

P1.3/T1 1 port 1.3 or Counter/Timer 1 input
P1.6/SCL 2 port 1.6 or I2C-bus clock line
P1.7/SDA 3 port 1.7 or I2C-bus data line
P2.0/TPWM 4 port 2.0 or Tuning PWM output
P3.0/ADCO/PWMO 5 port 3.0 or ADC0 input or PWM0 output
P3.1/ADC1/PWM1 6 port 3.1 or ADC1 input or PWM1 output
P3.2/ADC1/PWM2 7 port 3.2 or ADC2 input or PWM2 output
P3.3/ADC3/PWM3 8 port 3.3 or ADC3 input or PWM3 output
VSSC/P 9 digital ground for μ-Controller core and periphery
P0.5 10 port 0.5 (8mA current sinking capability for direct drive of LEDs)
P0.6 11 port 0.6 (8mA current sinking capability for direct drive of LEDs)
VSSA 12 analog ground of Teletext decoder and digital ground of TV-processor
SECPLL 13 SECAM PLL decoupling
VP2 14 2nd supply voltage TV-processor (+8V)
DECDIG 15 decoupling digital supply of TV-processor
PH2LF 16 phase-2 filter
PH1LF 17 phase-1 filter
GND3 18 ground 3 for TV-processor
DECBG 19 bandgap decoupling
AVL/EWD

(1)

20 Automatic Volume Levelling/East-West drive output
VDRB 21 vertical drive B output
VDRA 22 vertical drive A output
IFIN1 23 IF input 1
IFIN2 24 IF input 2
IREF 25 reference current input
VSC 26 vertical sawtooth capacitor
TUNERAGC 27 tuner AGC output
AUDEEM/SIFIN1
DECSDEM/SIFIN2
GND2 30 ground 2 for TV processor
SNDPLL/SIFAGC
AVL/SNDIF/REFO/
AMOUT

(1)

(1)

28 audio deemphasis or SIF input 1

(1)

29 decoupling sound demodulator or SIF input2

(1)

31 narrow band PLL filter/AGC sound IF

Automatic Volume Levelling/sound IF input/subcarrier reference

32

output/AM output
HOUT 33 (non controlled)
FBISO 34 horizontal output
AUDEXT/
QSSO/AMOUT
EHTO

(1)

flyback input/sand castle output

35

external audio input/QSS intercarrier out/AM audio output (non

36

controlled)
PLLIF 37 EHT/overvoltage protection input
IFVO/SVO 38 IF-PLL loop filter
VP1 39 IF video output/selected CVBS output
CVBSINT 40 main supply voltage TV-processor (+8V)
GND1 41 internal CVBS input
CVBS/Y 42 ground 1 for TV-processor
CHROMA 43 external CVBS/Y input
AUDOUT/AMOUT

(1)

44 chrominance input (SVHS)
INSSW2 45 2nd RGB/YUV insertion input
R2/VIN 46 2nd R input/V (R-Y) input
G2/YIN 47 2nd G input/U input

22

SERVICE MANUAL

SYMBOL PIN DESCRIPTION

B2/UIN 48 2nd B input/U (B-Y) input
BCLIN 49 beam current limiter input/(V-guard input, note2)
BLKIN 50 black current input/(V-guard input, note2)
RO 51 Red output
GO 52 Green output
BO 53 Blue output
VDDA

analog supply of Teletext decoder and digital supply of TV-processor

54

(3.3V)
VPE 55 OTP programming Voltage
VDDC 56 digital supply to core (3.3V)
OSCGND 57 oscillator ground supply
XTALIN 58 crystal oscillator input
XTALOUT 59 crystal oscillator output
RESET 60 reset
VDDP 61 digital supply to periphery (+3.3V)
P1.0/INT1 62 port 1.0 or external interrupt 1 input
P1.1/TO 63 port 1.1 or Counter/Timer 0 input
P1.2/INTO 64 port 1.2 or external interrupt 0 input

Notes

1)The function of pin 20, 28, 29, 31, 32, 35 and 44 is dependent on the IC version (mono intercarrier

FM demodulator/QSS IF amplifier and East-West output or not) and on some software control bits.

The valid combinations are given in table 2.

2)The vertical guard function can be controlled via pin 49 or pin 50. The selection is made by means of

the IVG bit in subaddress 2BH.

Table 2 Pin functions for various versions

IC version FM-PLL Version QSS Version

East-West

Y/N

CMB1/CM

BO bits

AM bit - - - - - 0 1 - 0 1

Pin 20 AVL EWD AVL EWD

Pin 28 AUDEEM SIFIN1

Pin 29 DECSDEM SIFIN2

Pin 31 SNDPLL SIFAGC

Pin 32 SNDIR

Pin 35 AUDEXT AUDEXT QSSO AMOUT AUDEXT QSSO AMOUT

Pin44 AUDOUT Controlled AM or audio out

N Y N Y

00 01/10/11 00 01/10/11 00 01/10/11 00 01/10/11

(1)

REFO

(2)

AVL/SNDIF

(1)

REFO

(2)

AMOUT REFO

(2)

AMOUT REFO

(2)

Notes

1)When additional(external) selectivity is required for FM-PLL system pin 32 can be used as sound IF

input. This function is selected by means of SIF bit in subaddress 28H.

2)The reference output signal is only available for the CMB1/CMBO setting of 0/1. For the other setings

this pin is a switch output.

23

SERVICE MANUAL

Fig.8 Pin Configuration (SDIP 64)

24

SERVICE MANUAL

1.2 Electronic switch circuit HEF4053
Triple 2-channel Analog
Multiplexer/Demultiplexer

1). Description

The HEF4053 is a triple 2-channel analog

multiplexer/demultiplexer with a common enable

E ). Each multiplexer/demultiplexer has two

input (
indepen-

dent inputs/outputs (Y

and Y1), a common

0

input/output (Z), and select inputs (Sn). Each also

contains two-bidirectional analog switches, each

with one side connected to an independent

input/output (Y

and Y1) and the other side

0

connected to a common input/output (Z).

With (

E ) LOW, one of the two switches is selected

2). Block Diagrams

Fig.9 Functional Diagram

(low impedance ON-state) by Sn. With

E

HIGH, all switches are in the high impedance

OFF-state, independent of S

and VSS are the supply voltage connections

V

DD

for the digital control inputs (S
The V

inputs/outputs (Y

between V

negative limit. V

to VSS range is 3 to 15V.The analog

DD

, Y1 and Z) can swing

0

as a positive limit and VEE as a

DD

may not exceed 15 V.

DD-VEE

to SC.

A

to SC and E ).

A

For operation as a digital

multiplexer/demultiplexer, V

(typically ground).

V

SS

is connected to

EE

25

SERVICE MANUAL

Fig. 10 Pinning Diagram

HEF4053P(N): 16-lead DIL; plastic

(SOT38-1)

HEF4053D(F): 16-lead DIL; ceramic

(cerdip)

(SOT74)

HEF4053T(D): 16-lead S0; plastic

(SOT109-1)

(): Package Designator North America

Pinning

Y

to Y0C

0A

Y

1A to Y1C

S

A

Independent inputs/outputs

to Sc Select inputs

E

to ZC Common inputs/outputs

Z

A

Independent inputs/outputs

Enable input (active LOW)

3. Function Table
Inputs Channel
E Sn On

L L Y

L H Y

0n-Zn

1n-Zn

H X none

Notes

H=HIGH state (the more positive voltage)

L=LOW state (the less positive voltage)

X=STATE is immaterial

Fig. 21 Schematic Diagram (One Switch)

Fig 11

Ratings

Limiting values in accordance with the Absolute Maximum System (IEC 134)

Supply voltage (with reference to V

) VEE -18 to + 0,5 V

DD

Note

To avoid drawing V

current out of terminal Z, when switch current flows into terminals Y, the voltage

DD

drop across the bidirecctional switch must not exceed 0, 4 V. If the switch current flows into terminal

Z, no V

the switch, but the voltages at Y and Z may not exceed V

current will flow out of terminals Y, in this case there is no limit for the voltage drop across

DD

DD

or V

EE.

26

SERVICE MANUAL

1.3 Sound power amplifier TDA7057AQ
2×8W Stereo BTL Audio Output Amplifier with DC Volume Control

1). Features

·DC volume control

·Few external components

·Mute mode

·Thermal protection

·Short-circuit proof

·No switch-on and switch-off clicks

·Good overall stability

·Low power consumption

·Low HF radiation

ESD protected on all pins.

·

2). General Description

The TDA7057AQ is a stereo BTL output amplifier

with DC volume control. The device is designed for

use in TVs and monitiors, but is also suitable for

battery-fed portable recorders and radios.

Missing Current Limiter (MCL)

A MCL protection circuit is built-in. The MCL circuit is

activated when the difference in current between the

output terminal of each amplifier exceeds 100 mA

(typical 300 Ma). This level of 100 mA allows for

single-ended headphone applications.

3). Block Diagram

Fig.12

27

SERVICE MANUAL

1.4 Vertical scan output stage circuit TDA8356/N6
DC-coupled vertical deflection circuit TDA8356

1) Features

● Few external components

● Highly efficient fully DC-coupled vertical output bridge circuit

● Vertical flyback switch

● Guard circuit

● Protection against:

Short-circuit of the output pins (7 and 4)

Short-circuit of the output pins to VP.

● Temperature protection

● High EMC immunity because of common mode inputs

● A guard signal in zoom mode.

2) General Description

The TDA8356 is a power circuit for use in 90, and 110, colour deflection systems for field frequencies of

50 to 120 Hz. The circuit provides a DC driven vertical deflection output circuit, operating as a highly

efficient class G system.

3) Block Diagra 4) Pinning

Fig.13 Fig.14

SYMBOL PIN DESCRIPTION

Idrive(pos) 1 input power-stage (positive); includes II(sb) signal bias
Idrive(neg) 2 input power-stage (negative); includes II(sb) signal bias
VP 3 operating supply voltage
VO(B) 4 output voltage B
GND 5 ground
VFB 6 input flyback supply voltage
VO(A) 7 output voltage A
VO(guard) 8 guard output voltage
VI(fb) 9 input feedback voltage

28

SERVICE MANUAL

1.5 Audio effect processor TDA7449
TDA7449 TONE CONTROLDIGITALLY CONTROLLED
AUDIO

PROCESSORINPUT MULTIPLEXER

1) Features

- 2 stereo inputs

- selectableinput gain for optimal Adaptationto different

sources One stereo output Treble, and bass control in 2.0db

Steps Volumecontrol in 1.0db steps Two speaker attenuators:

- two independentspeakercontrol In 1.0dbsteps for

balancefacility

- independent mute function All function are programmable via

Serial bus

2) descripion

The tda7449 is a volume tone (bass and treble) Balance

(left/right) processor for quality audio Applications in TV

systems.

Selectable input gain is provided. Control of all The functions is accomplished by serial bus.

The ac signal setting is obtained by resistor networks And switches combined with operational

Amplifiers.

Thanks to the used bipolar/cmostechnology, Low distortion, low noise and dc stepping are Obtained.

3) Block Diagram

Fig.15

29

4) Pin Connection

5) Electrical Characteristics

SERVICE MANUAL

Fig.16

30

SERVICE MANUAL

ELECTRICAL CHARACTERISTICS (refer to the test circuit Tamb = 25°C, VS = 9V,RL= 10KΩ,
RG = 600Ω, all controls flat (G = 0dB), unless otherwise specified)

NOTE1:

1) The device is functionally good at Vs = 5V. a step down, on Vs, to 4V does’t reset the device.

2) BASS and TREBLE response: The center frequency and the response quality can be chosen by the

external circuitry.

31

SERVICE MANUAL

1.6 EEPROM AT24C08

1) Features

·Data EEPROM internally organized as 1024/2048

bytes and 64/128 pages×16 bytes

·Page protection mode, flexible page-by-page

hardware write protection

-Additional protection EEPROM of 64/128 bits,
bit per data page
1-Protection setting for each data page by writing its
protection bit

-Protection management without switching WP pin

·Low power CMOS

·Vcc=2.7 to 5.5V operation

·Two wire serial interface bus, I

·Filtered inputs for noise suppression with Schmitt

trigger

·Clock frequency up to 400 kHz

·High programming flexibility

-Internal programming voltage

-Self timed programming cycle including erase

-Byte-write and page-write programming, between 1 and 16 bytes

-Typical programming time 6ms(<10ms) for up to 16 bytes

·High reliability

-Endurance 10

-Data retention 40 years

-ESD protection 4000 V on all pins

·8 pin DIP/DSO packages

·Available for extended temperature ranges

-Industrial: -40℃ to +85℃

-Automotive: -40℃ to +125℃

3) Block Diagram

6

cycles

1)

2

C-Bus compatible

1)

2) Pin Configuration

Fig. 17

32

SERVICE MANUAL

1.7 Power module STR-G5653/6454R

Switch-mode Power Supply STR- G5653/F6654

The Series STR-G5653/F6654 is specifically designed to satisfy the requirements for increased

integration and reliability in off-line quasi-resonant flyback converters. The series incorporates a

high-precise error amplifying control and drive circuit with discrete avalanche-rated power MOSFET,

featuring fewer external components, small-size and standard power supply.

Covering the power range from below 25 watts up to 300 watts for 100/115/230 VAC inputs, and up to

150 watts for 85 to 265 VAC universal input, these devices can be used in a range of applications,

from battery chargers and set top boxes, to televisions, monitors, and industrial power supply units.

Cycle-by-cycle current limiting, under-voltage lockout with hysteresis, over-voltage protection, and

thermal shutdown protects the power supply during the normal overload and fault conditions.

Low-current startup and a low-power standby mode selected from the secondary circuit completes

a comprehensive suite of features. The series is provided in a five-pin overmolded SIP style package,

affording dielectric isolation without compromising thermal characteristics.

1) Features

●Flyback Operation with Quasi-Resonant Soft Switching for Low Power Dissipation and EMI

●Rugged Avalanche-Rated MOSFET

●Soft drive circuit MOSFET

●Adjustable MOSFET switching speed

●Choice of MOSFET Voltage and rDS(on)

●Full Over-Current Protection (no blanking)

●Under-Voltage Lockout with Hysteresis

●Over-Voltage Protection

●Direct Voltage Feedback

●Low Start-up Current (100μAmax)

●Low-Frequency, Low-Power Standby Operation

●Overmolded 5-Pin Package

2). Circuit Block Diagram

Fig.18

33

SERVICE MANUAL

3). Pin Configuration and Functions

Fig.19

3.1) Pin function for STR-G5653

Pin No. Symbol Function Description

1 D MOSFET drain

2 S MOSFET source

3 GND Ground

4 VIN Supply voltage input for control circuit

5 OCP/FB Over-current protection detection signal/ voltage-limiting signal input

3.2) Pin function for STR-F6654

Pin No. Symbol Function Description

1 OCP/FB Over-current protection detection signal/ voltage-limiting signal input

2 S MOSFET source

3 D MOSFET drain

4 VIN Supply voltage input for control circuit

5 GND Ground

4). Difference between STR-G5653 and STR-F6654

a. Different size: STR- F6654 is larger

b. Different pin functions

c. Different electric characteristics: Larger power output, switching current, avalanche-rated and

internal allowable power consumption for STR-F6654

d. internal allowable power consumption for STR-F6654

34

SERVICE MANUAL

3. WAVEFORMS OF KEY POINTS

NI00

Pin58

NI00

Pin34

NI00

Pin33

NI00

Pin44

NI00

Pin22

BU250

8DX-B

NI00

Pin21

BSC60H

-HEAT

35

SERVICE MANUAL

BCT-4

Pin4

N100

-P40

Notes:

① The waveforms are only for reference.
② The waveforms may differ dependent on different models.

36

SERVICE MANUAL

4. KEY ICS SERVICE DATA

Table 3 Function and Service Data of TDA7057AQ (N600)’s Pins

Digital Multimeter : Victor DT890D

Pin

No.

1
2
3
4
5
6
7
8
9
10
11
12
13

Pin

No.

1
2
3
4
5
6
7
8
9

Pin

No.

1 Signal input 3.0 22.2 47.0
2 Signal input 3.9 22.2 47.0.
3 Signal input 1.3 21.2 40.0
4 Signal output 2.5 0 0
5 Signal input 2.4 - -

Vertical drive input (positive)
Vertical drive input (negative)
Feedback input
Supply voltage
Output 1
Not connected
Ground
Pump supply voltage input
Output 1
Guard output
Pincushion output
Pincushion input (negative)
Pincushion input (positive)

Idrive (pos)
Idrive (neg)
VP
VO (B)
GND
VFB
VO (A)
VO(guard)
VI(fb)

Function description

Function description

Table 4 Function and Service Data of TDA8356 (N401)’s Pins

Symbol

Table 5 Function and Service Data of HEF4053BP (N402)’s Pins

Reference

Voltage (V)

7.5 22.6 18.6
0 0 0.

7.5 22.6 18.6

7.5 22.6 18.6
0 0 0

7.5 22.6 18.6

0.8 8.7 8.8
0 0 0.

2.4 54.7 23.6

16.0 2.4 2.4

2.4 55.1 23.6
0 - -

0.8 9.0 8.8

Digital Multimeter : Victor DT890D

Reference

Voltage (V)

2.4 27.7 20.3

2.4 27.7 20.4.

15.4 26.3 13.5

7.7 6.1 6.1
0 0 0

45.0 113.3 13.7

7.5 6.1 6.1

0.2 10.0 9.7.

7.7 6.1 6.1

Digital Multimeter : Victor DT890D

Reference
Voltage (V)

Positive

Resistance

(KΩ)

Positive

Resistance

(KΩ)

Positive
Resistance
(KΩ)

Nerative

Resistance

(KΩ)

Nerative

Resistance

(KΩ)

Nerative
Resistance
(KΩ)

(continued)

37

SERVICE MANUAL

6 Ground 0 0 0
7 Ground 0 0 0
8 Ground 0 0 0.
9 Control signal input 0.03 13.5 13.1
10 Control signal input 0.03 13.5 13.1
11 Control signal input 0.03 13.5 13.1
12 Signal input 3.9 22.2 47.0
13 Signal output 0.7 22.2 47.0
14 Signal input 3.9 21.9 26.0
15 Audio output 3.9 21.9 26.0
16 Supply voltage 7.8 0 0

Table 6 Function and Service Data of TDA7449 (N650)’s Pins

Digital Multimeter : Victor DT890D

Pin

No.

Symbol

Reference

Voltage (V)

Positive

Resistance

(KΩ)

Nerative

Resistance

(KΩ)

1 CREF 4.0 28.2 21.9
2 VS 8.0 1.8 1.8
3 PGND 0 0 0
4 ROUT 3.3 9.4 9.3
5 LOUT 3.3 9.4 9.3
6 R_IN1 4.0 21.9 26.0
7 R_IN2 4.0 26.7 24.3.
8 L_IN1 4.0 26.7 24.3
9 L_IN2 4.0 21.9 26.1
10 MUXOUT(L) 4.0 24.5 22.5
11 MUXOUT(R) 4.0 24.5 22.5
12 BIN(R) 4.0 28.0 26.1
13 BOUT(R) 4.0 28.0 21.0
14 BOUT(L) 4.0 28.0 20.8
15 TREBLE(L) 4.0 28.0 26.1
16 BIN(L) 4.0 30.5 28.0
17 TREBLE(R) 4.0 30.5 28.0
18 DIG_GND 0 0 0
19 SCL 3.4 6.8 6.7
20 SDA 3.1 6.8 6.7

Table 7 Function and Service Data of TDA9351PS/N2/3I (N100)’s Pins

Digital Multimeter : Victor DT890D

Pin

No.

Symbol

Reference
Voltage (V)

Positive
Resistance
(KΩ)

Nerative
Resistance
(KΩ)

1 P1.3/T1 3.8 9.5 9.5

2 P1.6/SCL 3.4 6.8 6.8

(continued)

38

SERVICE MANUAL

3 P1.7/SDA 3.0 6.8 6.8

4 P2.0/TPWM 1.8 36.2 17.9

5 P3.0/ADC0/PWM0 0.1 11.8 12.3

6 P3.1/ADC1/PWM1 0.1 5.0 5.0

7 P3.2/ADC2/PWM2 0.02 13.5 13.5

8 P3.3/ADC3/PWM3 0.7 10.7 9.3

9 VSSC/P 0 0 0

10 P0.5 0.01 13.3 13.3

11 P0.6 4.2 11.6 11.0

12 VSSA 0 0 0

13 SECPLL 2.3 27.6 21.7

14 VP2 8.0 1.8 1.8

15 DECDIG 5.0 23.1 16.1

16 PH2LF 3.2 27.5 `21.0

17 PH1LF 3.9 27.9 21.2

18 GND3 0 0 0

19 DECBG 4.0 24.4 18.7

20 AVL/EWD (1) 0.01 27.6 21.2

21 VDRA 2.4 27.6 20.4

22 IFIN1 2.4 27.6 20.3

23 IFIN2 1.8 24.7 19.8

24 IREF 1.8 24.7 19.9

25 TUNERAGC 3.8 25.3 20.5

26 AUDEEM/SIFIN1(1) 3.8 27.7 21.5

27 DECSDEM/SIFIN2(1) 1.6 8.4 8.4

28 GND2 3.2 27.1 20.7

29 VSSA 2.3 27.8 21.6

30 SECPLL 0 0 0

31 SNDPLL/SIFAGC(1) 2.3 27.8 21.8

32 AVL/SNDIF/REF0/AMOUT(1) 0.2 27.2 20.4

33 HOUT 0.4 5.3 5.3

34 FBISO 0.5 24.0 18.8

35 AUDEXT/QSSO/AMOUT(1) 3.7 27.8 21.5

36 AUDEXT/ 1.6 18.7 16.0

37 QSSO/AMOUT(1) 2.4 27.8 21.5

38 AUDEXT/ 3.3 24.0 21.1

39 QSSO/AMOUT(1) 7.7 1.8 1.8

40 AUDEXT/ 3.8 27.5 21.2

41 GND1 0 0 0

42 CVBS/Y 3.3 27.5 21.2

(continued)

39

SERVICE MANUAL

43 CHROMA 1.4 26.8 20.9

44 AUDOUT /AMOUT(1) 3.3 27.5 21.5

45 INSSW2 1.6 1.0 1.0

46 R2/VIN 2.6 28.0 21.7

47 G2/YIN 2.6 28.0 21.7

48 B2/UIN 2.6 28.0 21.7

49 BCLIN 2.5 27.6 20.8

50 BLKIN 6.0 27.9 21.3

51 RO 2.6 1.1 1.1

52 GO 2.5 1.1 1.1

53 BO 2.4 1.1 1.1

54 VDDA 3.2 11.0 11.3

55 VPE 0 0 0

56 VDDC 3.2 11.0 11.3

57 OSCGND 0.02 - -

58 XTALIN - - -

59 XTALOUT - - -

60 RESET 0 0 0

61 VDDP 3.2 11.0 11.3

62 P1.0/INT1 0 - -

63 P1.1/T0 1.5 3.3 3.3

64 P1.2/INT0 5.0 18.2 17.5

Notes:

③ The data are only for reference.
④ The data sheet may differ dependent on different models.

40

SERVICE MANUAL

4. REPLACEMENT OF PARTS

4.1 Description

Many electrical and mechanical components in this chassis have special safety-related

characteristics. Components which have these special safety characteristics in this manual and its

supplements are identified by the international hazard symbols or UL, FCC, FDA or VDE marking

on the circuit diagram and parts list. When replacing any of these components, substitute the one

which has the same safety characteristics as specified in the manual.

41

CIRCUIT DIAGRAM FOR 21BM18

CRT RGB PCB

MAIN PCB

Final Wiring Diagram

Side-set AV PCB AssemblySide-set AV PCB Assembly

--

++

Wired Connector XS161AWired Connector XS161A

XS600XS600

XS800AXS800A

ed Connector XS161Wir

ed Connector XS161

Wired Connector XPK03Wired Connector XPK03

Wired Connector XPY01Wired Connector XPY01

Wir

XPK02XPK02

Control buttons PCB assemblyControl buttons PCB assembly

++

--

Wired Connector XPK02Wired Connector XPK02

XP320XP320

XS320XS320

Main PCB AssemblyMain PCB Assembly

XS200XS200

W01.000;XPY03W01.000;XPY03

W01.000;1W01.000;1

W01.000;4W01.000;4

2Wired Con

2

C909C909

nector XS40

nector XS40

W01.000;6W01.000;6

CRT's Ground WireCRT's Ground Wire

GNDGND

W01.000;XSY01W01.000;XSY01

SolderedSoldered

Wired Con

XS500XS500

A Wire (Red)A Wire (Red)

Remote Sensor PCB AssemblyRemote Sensor PCB Assembly

To Deflection YokeTo Deflection Yoke

XSA04XSA04

XSA05XSA05

From Power Switch Assembly

From Power Switch Assembly

To Degaussing CoilTo Degaussing Coil

B Wire (Grey)B Wire (Grey)

XSY03XSY03

30

Final Assembly Diagram (1)

or

Buttons Board Assembly

Red

Black

Yellow

36

37

Grey

Blue

38

Diagram B

21

Remote Sensor Board Assembly

See Diagram B

Side AV Board Assembly

1313

Final Assembly Diagram (2)

1313

AA

22

1111

A ViewA View

4040

2727

1313

3939

2727

YellowYellow

BlueBlue

KDYKDY

RedRed

88

GreenGreen

Final Assembly Diagram (3)

or

27

25

or

26

24

33

23

Final Assembly Diagram (4)

Diagram ADiagram A

2929

2828

M5M5

Wire clipWire clip

Binding wireBinding wire

Notched nutNotched nut

Notched nutNotched nut

Tapping screwTapping screw

Tapping screwTapping screw

4646
4545

4444
4343

4242

4141

P-32P-32

Q04-2Q04-2

Degaussing coil Degaussing coil

CRTCRT

Power cordPower cord
Power switchPower switch

SpeakerSpeaker
Plastic paintPlastic paint

White nitro magnetic paint Q04-2White nitro magnetic paint Q04-2

Tin solderTin solder

TapeTape

Wire clipWire clip

Tapping screwTapping screw

Tapping screwTapping screw

Tapping screwTapping screw

Tapping screwTapping screw

Tapping screwTapping screw

WasherWasher

Side AV LableSide AV Lable
Distance clipDistance clip
Wire clipWire clip

Wire clipWire clip

Wire clip AWire clip A

Tension springTension spring

Six-button assemblySix-button assembly

Six-button assemblySix-button assembly

Wired connector KDYWired connector KDY

Wired connector XS10BWired connector XS10B

Wired connector XS10AWired connector XS10A

Wired connector XS501Wired connector XS501

Back cover assemblyBack cover assembly

Front cover assemblyFront cover assembly

Ground WireGround Wire

Chassis assemblyChassis assembly

BlackBlack

SerialSerial

No.No.

Code No.Code No.

PartsParts

QtyQty

RemarksRemarks

SerialSerial

No.No.

Code No.Code No.

PartsParts

QtyQty

RemarksRemarks