COLOUR TV SET

Models:

29CT24FS

29CT71FS

SERVICE MANUAL

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SERVICE MANUAL

TABLE OF CONTENTS

SPECIFICATIONS

............................................................................................................. 1

SAFETY INSTRUCTIONS AND MAINTENANCE

......................................... 2

X-RAY RADIATION PRECAUTION

.......................................................................................... 2

SAFETY PRECAUTION

.............................................................................................................. 2

PRODUCT SAFETY NOTICE

.................................................................................................... 3

SAFETY SYMBOL DESCRIPTION

........................................................................................... 3

MAINTENANCE

............................................................................................................................ 4

ADJUSTMENTS

.................................................................................................................. 5

SET-UP ADJUSTMENTS

........................................................................................................... 5

CIRCUIT ADJUSTMENTS

.......................................................................................................... 8

STRUCTURE AND CHASSIS FUNCTION DESCRIPTION

.................... 18

STRUCTURE BLOCK DIAGRAM

............................................................................................. 18

BLOCK DIAGRAM FOR SUPPLY VOLTAGE SYSTEM

...................................................... 19

CHASSIS DESCRIPTION

...........................................................................................................20

SERVICE DATA

.................................................................................................................21

TECHNICAL DATA OF KEY ICS

...............................................................................................21

SERVICE DATA OF KEY ICS

....................................................................................................43

REPLACEMENT OF PARTS

.......................................................................................................46

APPENDIX

1. CIRCUIT DIAGRAM

2. FINAL ASSEMBLY DIAGRAM

3. FINAL WIRING DIAGRAM

4. PRINTED CIRCUIT BOARD LAYOUTS

1

SERVICE MANUAL

SPECIFICATIONS

Model Number

Color system

RF system

Sound system

Video system

Programs preset

Antenna input

Picture tube (Approx.)

Effective screen dimensions

Video/Audio inputs

Power source

Weight (Approx.)

Video/Audio outputs

Rated power consumption

Table 1 Specifications

29CT24FS, 29CT71FS

PAL, SECAM

B/G, D/K

PAL4.43, SECAM, NTSC3.58, NTSC4.43 (50/60Hz)

236(0-235)

75 (unbalanced)

478 363mm

Composite-3; component-1; S-video-1

170-260V ~, 50Hz

30kg

Composite - 1

110 W

Designs and specifications are subject to change without notice.

1

SERVICE MANUAL

INSTRUCTIONS FOR SERVICE SAFETY AND MAINTENANCE

WARNING: BEFORE SERVICING THIS CHASSIS, READ THE

“

X-RAY

RADIATION 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 TO 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).

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.

2

SERVICE MANUAL

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 YOUR 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 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.

U

L

3

SERVICE MANUAL 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. Place the TV set on a stable stand or base that is of adequate size and strength to prevent it from being accidentally tipped over, pushed off, or pulled off. 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:

2. Convergence

Notes:

① The purity/convergence magnet assembly and rubber wedges need mechanical positioning. Refer to Fig1, 2.

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.

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.

5

SERVICE MANUAL

Yok

Fig. 1

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 steps 2.1.3)～2.1.5) until optimal convergence is 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.

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.

6

SERVICE MANUAL

Fig. 2

4-pole Magnet Movement 6-pole Magnet Movement

Center Convergence by Convergence Magnets

Incline the Yoke Up (or Down) Incline the Yoke Right (or Left)

Circumference Convergence by DEF Yoke

Fig.3

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 I

2

C bus control, first change the bus data.

1. Degaussing

A degaussing coil is built inside the 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. Confirmation and Adjustment for Voltage

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

2.1 Power on the TV and receive Philips test pattern.

2.2 Check the resistors and coils for being burned. (If the fuse is burned out, do not power on the

TV again until the cause is found out.)

2.3 ---Measure voltages of test points with the digital voltmeter. Measure the CRT high voltage with the high-voltage testing equipment and heater voltage with the high-frequency effective voltmeter. The rated values are shown as below.

Test Point

Negative of VD871

Table 2

Voltage (V)

82V±5V in standby

134±1.5V in use

Test Point

Positive of C414

Positive of C879

Positive of C882

Positive of C117

5±0.5V

9±0.5V

32±1V

Negative of VD402A 12.5±1V

Negative of VD404 27±1.5V

Voltage (V)

5±0.5V

Positive of C412 9±0.5V

Negative of VD872 16±1V

Negative of VD873 16±1V

Negative of VD874 16±1V

Negative of VD403 190±5.0V

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

CRT.

3.2 Plug in the supply socket (150-250V, AC) and turn on the TV. Set the brightness and contrast

8

SERVICE MANUAL to minimum (0μA).

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

3.4 Change the brightness from minimum to maximum, and ensure high voltage not beyond the limitation in any case.

Nominal EHT voltage: 29.5±1.2KV Limited EHT voltage: 32KV

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.

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

Before Adjusting After Adjusting

Fig. 4

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 sec. 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.

6.1 To enter the SERVICE mode

Set the volume to 0 by the remote control. Then press and hold the MUTE button on the p remote control and MENU button on the TV at the same time for over 2 seconds. In the S mode, ress the POWER button to quit the S mode.

S

(“S”is red and other items are yellow.)

9

SERVICE MANUAL

Use the ↓/↑buttons on the remote control to highlight an adjustment and the ←/→ buttons to adjust it.

The POS+/-,↑/↓/←/→,1~6, RECALL, VOL+/-, MUTE and POWER buttons on the remote control function in the S mode, but 100+, 7, 8, 9 and 0 buttons not.

6.2

Adjustments for Service mode and design mode

Table 3

：

Bit Status

MODE0

Bit7.6 Audio system options (available during auto search and use of AUTO button)

Function switchover for CPU’s Pin 61

V MUTE

00: B/G 01: I 10: D/K 11: M

0: External mute 1: Audio system switchover

When changing channels: 0: Y- mute 1: RGB mute

MODE1

MODE2

Bit4

Bit3

Bit2

Bit1

Bit0

Bit7

Bit6

Bit5

Bit4

Bit 3

Bit 2

Bit 1

Bit1

Bit0

Bit7

Bit6

Bit5

Bit5

Bit4

Bit3

Bit2

Bit.0

SECAM gate pulse width

SECAM

Fixed to 00

Write-in LOGO option

Power-on modes

Step length setting for lighting up gradually during power-on

Screen saver setting

M option

D/K option

I option

B/G option

Arabic numeral

DVD setting bit for AV board TC90L01

Tilt correction setting bit

“

SVM”in PICTURE menu

TA1343/NICAM woofer output setting

“

WOOFER”in SOUND menu

Black-screen time setting

BBE AGC option

00: 2.2μS 01: 2.0μS

10:1.8μS 11: SECAM decoding disabled

0: No 1:Yes

0: No 1:Yes

0: Memory on 1: Soft on

1：Large step 0: Small step

0: No 1: Yes

0: No 1: Yes

0: No 1: Yes

0: No 1: Yes

0: No 1: Yes

0: Yes 1: No

0: No 1: Yes

0: No 1: Yes

0: No 1: Yes

0: Mono output 1: Overlapped to main channel

0: No 1: Yes

0: Short time 1: If OPT.2 = 1, long time; OPT.2 = 0, short time

1: 300mv 0: 150mv

MODE3

BIT 7

BIT 6

BIT 5.4

BIT 3

BIT 2

BIT 1

Relay switch option

Instant power-on option

Fixed to 00

BBE/SRS IC

TA1218

Multi AV switch options

1: Yes 0: No

1: Yes 0: No

1: Yes 0: No

BIT 0 BIT 1 BIT2

0 0 0 TV - AV1(S) - AV2 - AV3(S) - DVD

0 0 1 TV - AV1(S) - AV2 - AV3(S)

0 1 0 TV - AV1(S) - AV2 - DVD

0 1 1 TV - AV1(S) - AV2

(continued)

10

OPT

MODE4

LANG-OPT

When only with single language option, reset the CPU to enable the options.

LANG-OUT

BIT 7

BIT 7

BIT 6

BIT 5

BIT 4

BIT 3

BIT 2

BIT 1

BIT 0

BIT 6

BIT 5

BIT 4

BIT 3

BIT 2

BIT 1

BIT 0

Bit 7

Bit 6

Bit 5

Bit 4

Bit 3

Bit 2

Bit 1

Bit 0

OSD

RCUT

GCUT

BCUT

TC90A49 option

TA1343 option

TC90L01 option

TA1218 option

NA

NJW1161 option

NJW1160 option

NJW1137 option

Arabic

Farsi

Malay

Indonesian

Russian

German

French

English

Ex-factory language options with AUTO key

Interval between relay on and off

VCO adjustments

Audio processing

Large-amplitude AFT switch when no signal

Audio gain switch

Usage of Y-mute

Thailand B/G (5.74M)

Single audio system

Horizontal position of OSD

R cut off

G cut off

B cut off

SERVICE MANUAL

1 0 0 TV - AV1(S) - AV3(S) - DVD

1 0 1 TV - AV1(S) - AV3(S)

1 1 0 TV - AV1(S) - DVD

1 1 1 TV - AV1

0: No 1: Yes

0: No 1: Yes

0: No 1: Yes

0: No 1: Yes

0: No 1: Yes

0: No 1: Yes

0: No 1: Yes

0: No 1: Yes

0: No 1: Yes

0: No 1: Yes

0: No 1: Yes

0: No 1: Yes

0: No 1: Yes

0: No 1: Yes

0: No 1: Yes

00: English 01: French 02: German 03: Russian

04: Indonesian 05: Malay 06: Farsi 07: Arabic

0: No 1: Yes

0: PIF VCO functions (PIFVCO = 10) during auto search and search；

1: PIFVCO = 10 during turn-on，and PIFVCO = 00 in Normal mode

1: Yes 0: No

1: Off 0: On

1: Off 0: On

0: No 1: Yes

1: Yes 0: No

1: Yes 0: No

(continued)

11

COLC

TNTC

TNTCAV

COLP

COLS

SCOL

SCNT

SERVICE MANUAL

Color center (for NTSC)

Tint center (for NTSC)

Tint center (for NTSC IN AV)

Color center (for PAL)

Color center (for SECAM)

Sub color center (for DVD)

Y- sub contrast

ST3

SV3

ST4

SV4

SVD

Sharpness center for NTSC 3.58 (TV)

Sharpness center for NTSC 3.58 (VIDEO)

Sharpness center for other color system (TV)

Sharpness center for other color system (VIDEO)

Sub Sharpness center in DVD

DCBS

TXCX

RGCN

ABL

BIT 5

BIT 4

BIT 3.2

BIT 1.0

BIT 7

Bit 6

Bit 5.4

Bit 3.2

Bi t 1.0

CLTO BIT 7

Chroma data

BIT 6

(TV & not M)

BIT 5

Text RGB in user contrast Max.

Text RGB in user contrast Min.

Y peak limiter

OSD ABL

ABL start point

ABL gain

Blank SW

OSD level

Y gamma

Black stretch

Killer off

P/N ID

C gamma

12

0: Off 1: On

0: Active 1: Inactive

00: ABL start point: 0V 01: -0.15V

10: -0.30V 11: -0.45V

00: -0.2V 01: -0.4V

10: -0.6V 11: -0.8V

0: H, V blanking on 1: H, V blanking off

00: OSD level, 80 IRE 01: 70IRE

10: 60IRE 11: 50IRE

00: Off 01: Y point 90 IRE, Gain –3dB

10: 80IRE 11: 70IRE

00: Off 01: Black stretch point, 25 IRE

10: 35IRE 11: 45IRE

0: Normal 1: Always killer off

0: PAL/ NTSC killer sensitivity, 1mVpp 1: 10mVpp

0: Color gamma off 1: On

(continued)

SERVICE MANUAL

CLTM

(TV & M)

CLVD(DVD)

CLVO(50hz)

/CLVM（60hz）

(VIDEO)

BIT 4.3

BIT 2.1.0

DEF

NTSC matrix

Y DL

00: USA (105 degree) 01: Japan (93 degree)

10: DVD 11:

000: -40 nsec 001: 0 010: 40 nsec 011: 80 nsec

100: 120 nsec 101: 160 nsec 110: 200 nsec 111: 240 nsec

BIT0 = 0: V AGC reference depends on YC VCC; BIT0 = 1: V AGC reference depends on integrated regulator

HPOS

VP50

50Hz horizontal phase

V phase (50Hz)

00: -3usec 10: 0 1F: +3usec

0: V phase delay, 0H 7: 7H

00: -50% 20: 0% 3F: 50%

WIDS

ECCT

ECCB

VEHT

HEHT

SBY

HPS

VP60

HITS

Adjusting difference between horizontal centers in PAL and NTSC

V phase (60Hz)

0: V phase delay, 0H 7: 7H

Adjusting difference between vertical amplitudes in PAL and NTSC

VLIN V-linearity

0: -15% 8: 0% F: 15%

0: -16% 8: 0% F: 16%

VLIS

VSS

Adjusting difference between vertical linear in PAL and NTSC

Correction for shift data of 50 Hz/ 60 Hz

00: 0Vpp 20: 1.4Vpp 3F: 2.8Vpp

DPCS

Shift data of EW parabola

Vertical amplitude in 16:9 mode (PAL)

HIT69

DPC69

EW parabola 16:9 in 16:9 mode (PAL)

HIT69S

Vertical amplitude in 16:9 mode (NTSC)

EW parabola 16:9 in 16:9 mode (NTSC)

DPC69S

KEY Trapezium

KEYS

Shift data of trapezium

00: -13% 20: 0% 3F: 13%

00: 1.5V V20: 4V 3F: 6.5V

Shift data of H size

EW corner top

EW corner bottom

V EHT gain

H EHT gain

Use in SECAM

00: -1.5V 10: 0V 1F: 1.5V

00: -1.5V 10: 0V 1F: 1.5V

0: 0% 4: 5% 7: 10%

0: 0% 4: 5% 7: 10%

SRY

BRTS

Use in SECAM

Sub brightness (difference)

00: IF mute 01: 65dBu 3F: 100dBu

(continued)

13

HAFC

V01

V25

V50

V100

Woofer

BIT 3.2

AFC gain

(in VIDEO mode)

BIT 1.0

AFC gain

(in TV mode)

Volume output data at 1%

Volume output data at 25%

Volume output data at 50%

Volume output data at 100%

TA1343 woofer Max.

SERVICE MANUAL

Data Description

Blanking Period Picture Period

0 0 3 1

0 1 4/7 2/7

1 0 4/3 1

1 1 Off Off

Data Description

Blanking Period Picture Period

0 0 3 1

0 1 4/7 2/7

1 0 4/3 1

1 1 Off Off

FLG0

FLG1

REFP

RSNS

GSNS

BSNS

BIT 7

BIT 2

BIT 1

BIT 0

BIT 5

BIT 4

AKB pulse position

R SENSE

G SENSE

B SENSE

Bit 6.5.4

Readjust VCO when selecting position 0: Enable 1: Disable

N buzz cancel

AFT window SW

0: Nyquist buzz cancel, on 1: Off

0: Wide (-/+ 250kHz) AFT sensitivity, for channel search

1: Narrow (83kHz) For normal operation

Over modulation 0: Normal 1: PIF over modulation switch on

MIX GAIN

Sync separation.

0: SIF 1MHz convert gain, low gain 1: High gain

0: Sync separation level 40% 1: 36%

000: 0H 001: 1H 010: 2H 011: 3H

100: 4H 101: 5H 110: 6H 111: 7H

00: x 0 20: x 0.5 3F: x 1.0

PIF FREQUENCY

00: x 0 20: x 0.5 3F: x 1.0

00: x 0 20: x 0.5 3F: x 1.0

001: 45.75 MHz 011: 38.9 MHz 100: 38.0 MHz

MOD

STBY

SVM BIT.4

SVM1

SVM3

VBLK

VCEN

UCOM

Bit 1.0

BIT 3.2

BIT 1.0

Data when SVM off

Data when SVM on

BIT 3.2

AKB MODE

VCD STANDBY

IF Standby

V blanking stop point

00: AKB off 01: ACB (cutoff: align to targets)

10: ADB (drive: align to targets) 11: AKB (cutoff/drive: align to targets)

00: Normal 01: Normal

10: Normal 11: VCD Standby

00: Normal 01: Normal

10: Normal 11: IF Standby

1:co max=1（-0.65 to +0.85） 0: co max=0（cutoff range:

-0.65 to +0.65)

00: 310H(50hz) 263H(60hz) 01: 299H(50hz) 254H(60hz)

10: 295H(50hz) 250H(60hz) 11: 291H(50hz) 246H(60hz)

BIT 1.0 V blanking start point

00: 23H(50hz) 22H(60hz) 01: 33H (50hz)30H(60hz)

10: 37H (50hz)34H(60hz) 11: 41H(50hz) 38H(60hz)

Vertical centering

BIT 1.0

BIT5.4.3

00: -32% 20: 0% 3F: 30%

Internal ADC

Improving NTSC color signal-to-noise ratio

00: GND 01: R output

10: B output 11: Monitor RF AGC via ADC

Available range: 000….011

(continued)

14

PYNX

PYNN

PYXS

PYNS

BASC

BASX

TREC

BALC

BAS1

TRE1

TRE3

WFL3

WON1

WON2

NVOL

WFL1

BAS2

TRE2

WFL2

BAS3

SERVICE MANUAL

Normal H.SYNC Max. 0-----------3F

Normal H.SYNC Min.

ASM/Search H.SYNC Max.

ASM/Search H.SYNC Min

Bass volume Center

Bass volume Max.

Treble volume Center

Balance volume Center

Bass in MUSIC mode setting

Treble in MUSIC mode setting

0-----------3F

0-----------3F

0-----------3F

Woofer in MUSIC mode setting

Bass in NEWS mode setting

Treble in NEWS mode setting

Woofer in NEWS mode setting

Bass in THEATRE mode setting

Treble in THEATRE mode setting

Woofer in THEATRE mode setting

TA1343 Max. woofer setting. The bigger the setting the smaller Max. woofer.

Woofer linear setting

Prescale NICAM

B1(12345)

B2(12345)

B3(12345)

BBE

OSDF

NOIS

VATT

COM1

(TC90A49)

COM2

(TC90A49)

BIT 2

BIT 7-BIT 0

AFC gain data setting in TV mode: 1: Adjust AFC gain in the lowest two bits of HAFC 0: With weak signal received, AFC gain = 0x10; with strong signal received, AFC gain = 0x00

Criterion of signal strength: >NOIS: Weak signal

<= NOIS: Strong signal

Audio ATT 00:-85DB or less 7F:0DB (7 BITS)

BIT 3

BIT 2.1.0

Pedestal clip

VENH2.1.0

0: On 1: Off

000: 0db(x1) …… 111: 3.52db(x1.5)

BIT 7.6.5.4

BIT 3

BIT2

BIT 1.0

Set vertical enhancer non-linear point

Set Y output horizontal peaking gain

Set Y output horizontal peaking on/off

Set vertical enhancer coring level

0000: 4LSB …… 1111: 64LSB

0: 1.5dB 1: 3.0dB

0: On 1: Off

00: 0LSB …… 11: 3LSB

NICAM chip five-equalizer data when the sound mode set to MUSIC:

B11 (for 120Hz) B12 (for 500 Hz) B13 (for 1.5KHz) B14 (for 5KHz) B15 (for 10KHz)

NICAM chip five-equalizer data when the sound mode set to NEWS:

B21 (for 120Hz) B22 (for 500 Hz) B23 (for 1.5KHz) B24 (for 5KHz) B25 (for 10KHz)

NICAM chip five-equalizer data when the sound mode set to THEATRE:

B31(for 120Hz) B32 (for 500 Hz) B33 (for 1.5KHz) B34 (for 5KHz) B35 (for 10KHz)

Highest four bits：BBE contour (0dB to 15dB); Lowest four bits: BBE process (0dB to 15dB)

OSD frequency setting

15

SERVICE MANUAL

6.3 Adjustments and Bus data

Table 4

Item Data Item Data Item Data Item Data

* MODE0

* MODE1

A6

35

CNTC

CNTN

40

08

# HITS

# VLIN

04

0C

GSNS

BSNS

00

00

10 SVM3 06

18 VBLK 00

C-MT 99 ST4 28 HIT69S 01 VTST 00

01 PYNX 2E

03 PYNN 18

08 BASX 70

# GCUT

# BCUT

# GDRV

30

30

40

CLTO

CLTS

* CLTM

3F

30

23

# SRY

# BRTS

# RAGC

08

17

18

TRE1

WFL1

BAS2

40

46

20

(continued)

16

SERVICE MANUAL

SCOL 00 #

SCNT 09 #

Notes:

①

The data sheet may differ dependent on different models.

②

The data sheet may differ dependent on different CRTs for the same model.

③

The data marked with “*”can be adjusted.

17

SERVICE MANUAL

STRUCTURE AND CHASSIS FUNCTION DESCRIPTION

1. STRUCTURE BLOCK DIAGRAM

l

L Speaker r

R Speaker

18

SERVICE MANUAL

2. BLOCK DIAGRAM FOR SUPPLY VOLTAGE SYSTEM

19

SERVICE MANUAL

3． CHASSIS DESCRIPTION

General Description

CN-18ED chassis is applied in PF2939E. By use of Toshiba V/C/D-MCU 2IN1 IC for TV small signal processing and bus control, the chassis enables TV tuning, adjustment, control and picture correction, featuring high-integration, high-performance-to-price ratio and high-reliability and compact circuit with fewer external components. The chassis, widely used in small and medium TVs, provides much more convenience for manufacturing and technical service. It includes:

2IN1 IC TMAP8827PSNG with function of E/W correction for PAL/NTSC/SECAM small signal processing and bus control

EEPROM AT24C16 for data memory

LA78040 /LA78041for vertical output power amplifying

TDA8944J (mono) for audio power amplifying

Thick-film IC STR-G8656 for power circuit adjustment and control

AV control TC90L01N

The following features are available in the chassis:

Color systems: PAL/ SECAM

Sound systems: D/K B/G

236 programs preset

Multilingual on screen display

I

2

C bus control

NICAM/AV stereo

Selectable picture/sound modes

Intelligent lock

Message board

Telephone directory

Game

Biorhythm

Calendar inquiry

The chassis mainly uses the following ICs and assemblies.

Serial No. Position

Table 5 Key ICs and Assemblies

Type Description

EERPOM

N210 CH08T0605 (TMPA8827PSNG) 2IN1 IC (Small signal processor + micro control (UOC)) 2

3

4

5

N603

N301

N801

TDA8944J

LA78040/LA78041

STR-G8656

Stereo audio power amplifier

Vertical scan output stage circuit

Switch-mode power supply control

Tuner

20

SERVICE MANUAL

SERVICE DATA

TECHNICAL DATA OF KEY ICS

1. TOSHIBA 2IN1 IC SERIES TMPA8827CMBNG /CPNG/CSNG

MCU AND SIGNAL PROCESSOR FOR A PAL/NTSC/SECAM TV

The TMPA8827CMNG /CPNG /CSNG is an integrated circuit for a PAL/ NTSC/SECAM TV. A MCU and a TV signal processor are integrated in a 64-pin shrink DIP package. The MCU contains 8-bit CPU, ROM, RAM, I/O ports, timer/ counters, A/D converters, an on-screen display controller, remote control interfaces, IIC bus interfaces and the Closed Caption decoder.

The TV signal processor contains PIF, SIF, Video, multi-standard chroma, Deflection, RGB processors. Fig. 6

MROM: TMPA8827CMNG (ROM: 32k)

TMPA8827CPNG (ROM: 48k)

TMPA8827CSNG (ROM: 64k)

OTP: TMPA8827PSNG

Weight: 8.85 g (typ.)

1) Features

MCU

□

High speed 8-bit CPU (TLCS-870/X series)

□

Instruction execution time: 0.5 μs (at 8 MHz)

□

(TMPA8827CMNG)

32-Kbytes ROM, 2-Kbytes RAM

(TMPA8827CPNG)

48-Kbytes ROM, 2-Kbytes RAM

(TMPA8827CSNG)

64-Kbytes ROM, 2-Kbytes RAM

□

ROM correction

□

12 I/O ports

□

14-bit PWM output 1 ch for a voltage synthesizer

□

7-bit PWM output 1 channel

□

8-bit A/D converter 3 ch for a touch-key input with key ON wake-up CIRCUIT

□

Remote control signal preprocessor

□

Two 16-bit internal timer/counter 2 ch

CCD Decoder

Digital data slicer for NTSC

OSD

□ Clock generation for OSD display

□

Font ROM characters: 384 characters

□

Characters display: 32 columns × 12 lines

□ Composition: 16 × 18 dots

□

Size of character: 3 (line by line)

□

Color of character: 8 (character by character)

□ Display position: H 256/V 512 steps

□

BOX function

□

Fringing, smoothing, Italic, underline function

□ Conform to CCD REGULATION

□

Jitter elimination

21

SERVICE MANUAL

□

Two 8-bit internal timer/counter 2 ch

□

Time base timer, watchdog timer

□ 16 interrupt sources: external 5, internal 11

□

IIC bus interface (multi-master)

・

TV Processor

IF

Integrated PIF VCO aligned automatically

Negative demodulation PIF

Multi-frequency SIF demodulator without external Tank-coil

Video

Integrated chroma traps

Black stretch

Y-gamma

Chroma

Integrated chroma BPFs

PAL/NTSC/SECAM demodulation

RGB/Base-Band

Integrated 1 H base-band delay line

Base-band TINT control

Internal OSD interface

Half-tone and transparent for OSD

External YCbCr interface for DVD

RGB cut-off/drive controls by bus

ABCL (ABL and ACL combined)

Sync.

Integrated fH ×640 VCO

DC coupled vert. ramp output (single)

EW correction with EHT input

22

2) Block Diagram

SERVICE MANUAL

Fig. 7 Block diagram

23

SERVICE MANUAL

6

7

8

9

2

3

4

5

10

11

3) Basic Structure

3.1) Internal Connections

TMPA8827 has two pieces of IC chip in one package, using Multi-Chip-Package (MCP) technology.

One is a micro controller (MCU) and the other one is a signal processor (SP) for a color TV. There are some internal connections between these two ICs for handling below signals.

Table 6

Signal Name Direction Description

No.

Signal Name Direction Description

1 SCL M to S Internal IIC bus SCL

SDA

OSD R

OSD G

OSD B

OSD Y/BL

OSD I, CS OUT

C-Video

C-Sync

HD

VD

Bi-direction

M to S

M to S

M to S

M to S

M to S

S to M

S to M

S to M

S to M

Internal IIC bus SDA

OSD signal connection

OSD signal connection

OSD signal connection

OSD display control

OSD half-tone control/Test pattern signal

Composite video signal from internal video switch, for CCD

Composite sync. signal from sync. Separator, for CCD

Horizontal timing pulse regenerated from FBP, for OSD

Vertical timing pulse from sync. Separator, for OSD

12 CLK M to S 8 MHz clock

13 AV

DD

14 ADC

M to S

S to M

Reference voltage for C-Video interface

A/D converter monitoring RF-AGC, R-Y and B-Y

Functions of SP from MCU are controllable through the IIC bus of the internal connections.

3.2) Power Supply

TMPA8827 has some power supply and GND pins. Power supplies related MCU must be applied at the first. Power supplies for H.VCC and TV D.VCC are the second with at least 100 ms delay after

MCU power ON. The other power supplies are the last, which are recommended to be supplied from a regulator circuit using FBP.

3.3) Crystal Resonator

TMPA8827 requires only one crystal resonator, in stead that a conventional two-chip solution requires two resonators at least, one for MCU and the other one for SP. An oscillation clock with the crystal resonator of TMPA8827is supplied for MCU operation, PIF VCO automatic alignment, alignment free AFT, chroma demodulation and horizontal oscillation. The oscillation frequency is very important so that those of functions work properly, so that designing the oscillation frequency accurately is required. The spec of crystal is recommended to be within fosc: 8 MHz +/-20 ppm ftemp: 8 MHz +/-40 ppm (-20°C to +65°C)

While RESET of MCU is active, the MCU function stops. Hardware and software initialization sequence including power supplies control is required, because status of any hardware after the

24

SERVICE MANUAL

RESET period is unknown especially horizontal oscillator which is a very basic timing generator of

SP operation.

4) Terminal Interface

MCU Block

Pin No. Pin Name Interface Ci I/O

1

2

P61/LED1/ADC 8 bit

(/KWU5)

(AIN5)

(LED1)

P60/ADC 8 bit

(/KWU4)

(AIN4)

I/O

(input)

(input)

(output)

I/O

(input)

(input)

3

P53/ADC 8 bit/TC1/Int2

(/KWU0)

(AIN0)

(TC1)

(INT2)

I/O

(input)

(input)

(input)

(input)

Table 7

Function

Key on wake up input

A/D converter analog input

High current sink open drain output

Key on wake up input

A/D converter analog input

Key on wake up input

A/D converter analog input

Timer/counter input

External interrupt input

5 /Reset

6

7

9

54

55 uP

MPAGND uP AVDD

5 V

56 P56

57

P52/SDA

(SDA)

58

XOUT

XIN

8 TEST uP DVDD

5 V

P51/SCL

(SCL)

Power

Supply

GND

I/O

Reset signal input or watchdog timer output

Address trap reset output

Output

Input

X’tal connecting pins

Input

Test pin for out-going test.

Be tied to low.

Power

Supply

VDD

Supply 5 V

Power

Supply

Power

Suppl

Power

Supply

GND for Slicer circuit

GND for

Oscillator circuit

VDD for OSD Oscillator circuit

Supply 5 V

I/O

I/O IIC bus serial

(I/O) data input/output

IIC bus serial

I/O

(I/O) clock input/output

59

P50/PWM 7 bit/TC2/ I/O

Int0

(/PWM8)

(output)

(input)

7-bit D/A conversion (PWM) output

Timer/Counter input

External interrupt input

(continued)

25

SERVICE MANUAL

16

17

18

19

20

60

61

62

63

64

(TC2)

(/INT0)

P40/PWM 14 bit

(/PWM0)

P20/Int5/Stop

(/INT5)

(/STOP)

P31/Int4/TC3

(INT4)

(TC3)

P30/Int3/RXIN

(INT3)

(RXIN)

P63/LED2/

(LED2)

Signal Processor Block

Pin No.

11

12

13

22

23

24

(input)

I/O

(output)

I/O

(input)

(input)

I/O

(input)

(input)

I/O

(input)

(input)

I/O

(output)

14/12-bit D/A conversion (PWM) output

External interrupt input

STOP mode release signal input

External interrupt input

Timer/Counter input

External interrupt input

Remote control signal

Preprocessor input

High current sink open drain output

Pin Name

TV AGND

FBP in

HOUT

Table 8

Function

GND terminal for Analog block.

Input terminal for FBP.

Output terminal for Horizontal driving pulse.

Terminal to be connected capacitor for HAFC filter.

This terminal voltage controls H VCO frequency.

Terminal to be connected capacitor to generate V saw signal.

V saw amplitude is kept constant by V AGC function.

Output terminal for Vertical driving pulse.

VCC terminal for DEF circuit. Supply 9 V.

Terminal to be connected capacitor for SECAM filter.

V OUT

H.VCC 9 V

S Filter

Cb input

Y input

Input terminal for Cb signal.

Input terminal for Y signal. (Input level =1 Vp-p

Input terminal for Cr signal. It is recommended that input impedance is low.

GND terminal for Digital block. TV DGND

CIN Input terminal for Chroma signal.

EXT CVBS/Y (V2 Input terminal for Video signal.

IN) (Input level =1 Vp-p)

VCC terminal for Digital block.

This terminal voltage is clipped about 3.3 V by regulator circuit.

Supply TV DVCC voltage from HVCC

(continued)

26

SERVICE MANUAL

27

28

29

31

32

33

ABCL

Ew out

IF VCC 9 V

SIF out

EHT in

H.correc/SIF in

(#17) voltage via 270Ω.

Output terminal for fsc wave signal.

(Output level =0.55Vp-p typ.)

Input terminal for ABL/ACL control.

Output terminal for East-West correction signal.

VCC terminal for IF circuit.

Supply 9 V.

Output terminal for detected PIF signal.

(Output level =2.2 Vp-p)

Output terminal for detected SIF signal.

Input terminal for EHT feedback signal.

Input terminal for H correction and 2 nd

SIF.

Terminal to be connected capacitor for DC Negative

Feedback from SIF Det. output.

36

38

40

41

42

43

44

IF VCC 5V

37 S-Reg.F

Terminal to be connected with loop filter for PIF PLL.

This terminal voltage is controlled

PIF VCO frequency.

VCC terminal for IF circuit.

Supply 5 V.

Terminal to be connected capacitor for stabilizing internal bias.

Terminal to be connected capacitor for SIF Det.

De-Emphasis.

Deemph/

Audio out

IF GND

IF IN

Terminal to be connected with IF

AGC filter.

GND terminal for IF circuit.

Input terminals for IF signals.

Pin 41 and Pin 42 are both input poles of differential amplifier.

Output terminal for RF AGC control level. RF AGC

YC VCC 5 V

VCC terminal for Y/C circuit.

Supply 5 V. out

Output terminal for CVBS or Y signal selected by BUS

(video SW).

Terminal to be connected with

Black Det. filter for black stretch.

47

48

APC Fil.

(Chrome PLL filter)

IKin

Terminal to be connected with

APC filter for Chroma demodulation.

This terminal voltage controls frequency of VCXO.

Input terminal to sense AKB cathode current.

(continued)

27

SERVICE MANUAL

49 RGB VCC9 V

50

51

52

53

ROUT

GOUT

BOUT

TV AGND

5) Microcontrollers Descriptions

VCC terminal for RGB circuit.

Supply 9 V.

Output terminal for R signal.

Output terminal for G signal.

Output terminal for B signal.

GND terminal for Analog block.

Fig. 8 Functional Diagram

6) Refer to Table 13 about Functions and Data of the IC’s Pins.

28

SERVICE MANUAL

2. AUDIO POWER AMPLIFIER TDA8944J

2 X 7 W STEREO BRIDGE TIED LOAD (BTL) AUDIO AMPLIFIER

1) General description

The TDA8944J is a dual-channel audio power amplifier with an output power of

2

× 7 W at an 8 Ω load and a 12 V supply. The circuit contains two Bridge Tied Load

(BTL) amplifiers with an all-NPN output stage and standby/mute logic. The TDA8944J comes in a 17-pin DIL-bent-SIL (DBS) power package. The TDA8944J is printed-circuit board (PCB) compatible with all other types in the TDA894x family.

One PCB footprint accommodates both the mono and the stereo products.

2) Features

❷

Few external components

❷

Fixed gain

❷

Standby and mute mode

❷

No on/off switching plops

❷

Low standby current

❷

High supply voltage ripple rejection

❷

Outputs short-circuit protected to ground, supply and across the load

❷

Thermally protected

❷

Printed-circuit board compatible.

3) Block diagram

Fig 9. Block diagram.

29

SERVICE MANUAL

4) Pinning information

4.1) Pinning

Fig 10. Pin configuration.

30

SERVICE MANUAL

4.2) Pin description

Symbol Pin

OUT1

−

GND1

1

2

V

CC1

OUT1

+

3

4 n.c. 5

IN1

+

6 n.c. 7

IN1

−

8

IN2

−

MODE

9

10

SVR

IN2

+

11

12 n.c. 13

OUT2

−

14

GND2 15

V

CC2

OUT2+

16

17

Table 9: Pin description

Description

negative loudspeaker terminal 1 ground channel 1 supply voltage channel 1 positive loudspeaker terminal 1 positive input 1

Negative input 1

Negative input 2

Mode selection input (standby, mute, operating)

Half supply voltage decoupling (ripple rejection)

Positive input 2

Negative loudspeaker terminal 2

Ground channel 2

Supply voltage channel 2

Positive loudspeaker terminal 2

TDA8944J: Stereo power amplifier, Max output power: 2×7W

5) Refer to Table 14 about Functions and Data of the IC’s Pins.

31

SERVICE MANUAL

3. VERTICAL SCAN OUTPUT STAGE CIRCUIT LA78040/LA78041

Both LA78040/LA78041 are vertical scan output stage power amplifiers. But there is a little bit difference between the two amplifiers, that is, LA78040 has supply voltage of 24V and output current of 1.8A

P-P while LA78041 has supply voltage of 30V and output current of 2.2A

P-P

.

LA7840 (N301)

Vertical Deflection Output Circuit

1) Features

Low power dissipation due to built-in pump-up circuit

·Vertical output circuit

·Thermal protection circuit built in

·Excellent crossover characteristics

DC coupling possible

Package Type: TO-220-7H

Fig. 11

2) Block Diagram

Fig.12 Block diagram

3) Refer to Table 15 about Functions and Data of the IC’s Pins.

32

SERVICE MANUAL

4.EEPROM AT24C04/08/16

1) Features

Low-voltage and Standard-voltage Operation

-2.7 (Vcc=2.7V to 5.5V)

-1.8 (Vcc=1.8V to 5.5V)

Internally Organized 128x8(1K), 256x8 (2K), 512x8 (4K),

1024x8 (8K) or 2048x8 (16K)

2-wire Serial Interface

Schmitt Trigger, Filtered Inputs for Noise Suppression

Bi-directional Data Transfer Protocol

100kHz (1.8V, 2.5V, 2.7V) and 400 kHz (5V) Compatibility

Write Protect Pin for Hardware Data Protection

8-byte Page (1K, 2K), 16-byte Page (4K, 8K, 16K) Write Modes

Partial Page Writes are allowed

Self-timed Write Cycle (10 ms max)

High-reliability

-Endurance: 1 Million Write Cycles

- Data Retention: 100 Years

Automotive Grade and Extended Temperature Devices Available

8-lead PDIP, 8-lead JEDEC SOIC, 8-lead MAP and 8-lead TSSOP Package

2-wire

Serial EEPROM

AT24C01A 1K (128 x 8)

AT24C02 2K (256 x 8)

AT24C04 4K (512 x 8)

AT24C08 8K (1024 x 8)

AT24C16 6K (2048 x 8)

2) Description

The AT24C01A/02/04/08/16 provides 1024/2048/4096/8192/16384 bits of serial electrically erasable and programmable read-only memory (EEPROM) organized as 128/256/512/1024/2048 words of 8 bits each. The device is optimized for use in many industrial and commercial applications where low-power and low-voltage operations are essential. The

AT24C01A/02/04/08/16 is available in space-saving 8-pin PDIP, 8-lead JEDEC SOIC, 8-lead MAP and 8-lead TSSOP packages and is accessed via a 2-wire serial interface. In addition, the entire family is available in 2.7V (2.7V to 5.5V) and 1.8V (1.8V to 5.5V) versions.

33

SERVICE MANUAL

3) Pin Configuration

Pin Name

SCL

Function

Serial Clock Input

A0

A1

A2

GND

3

4

1

2

8-lead TSSOP

6

5

8

7

8-lead MAP

VCC

WP

SCL

SDA

VCC

WP

SCL

SDA

8

7

6

5

1

2

3

4

A0

A1

A2

GND

Bottom View

Fig. 13

A0

A1

A2

GND

1

2

3

4

8-pin PDIP

8

7

6

5

VCC

WP

SCL

SDA

A0

A1

A2

GND

1

2

3

4

8-lead SOIC

6

5

8

7

VCC

WP

SCL

SDA

Fig. 14

4) Pin Description

SERIAL CLOCK (SCL): The SCL input is used to positive edge clock data into each EEPROM device and negative edge clock data out of each device.

SERIAL DATA (SDA): The SDA pin is bi-directional for serial data transfer. This pin is open-drain driven and may be wired with any number of other open-drain or open-collector devices.

DEVICE/PAGE ADDRESSES (A2, A1, A0): The A2, A1 and A0 pins are device address inputs that are hard wired for the AT24C01A and the AT24C02. As many as eight 1K/2K devices may be addressed on a single bus system (device addressing is discussed in detail under the Device

Addressing section).

The AT24C04 uses the A2 and A1 inputs for hard wire addressing and a total of four 4K devices may be addressed on a single bus system. The A0 pin is a no connect.

The AT24C08 only uses the A2 input for hardwire addressing and a total of two 8K devices may be addressed on a single bus system. The A0 and A1 pins are no connects.

The AT24C16 does not use the device address pins, which limits the number of devices on a single bus to one. The A0, A1 and A2 pins are no connects.

34

SERVICE MANUAL

WRITE PROTECT (WP): The AT24C01A/02/04/16 has a Write Protect pin that provides hardware data protection. The Write Protect pin allows normal read/write operations when connected to ground (GND). When the Write Protect pin is connected to Vcc, the write protection feature is enabled and operates as shown in the following table.

WP Pin

Status

At Vcc

Part of the Array Protected

Table 10

Full (1K)

Array

Full (2K)

Array

Full (4K)

Array

Normal

Read/

Write

Operation

Upper

Half

(8K)

Array

At GND Normal Read/Write Operations

5) Memory Organization

・

AT24C01A, 1K SERIAL EEPROM: Internally organized with 16 pages of 8 bytes each, the 1K requires a 7-bit data word address for random word addressing.

・

AT24C02, 2K SERIAL EEPROM: Internally organized with 32 pages of 8 bytes each, the 2K requires an 8-bit data word address for random word addressing.

・

AT24C04, 4K SERIAL EEPROM: Internally organized with 32 pages of 16 bytes each, the 4K requires a 9-bit data word address for random word addressing.

・

AT24C08, 8K SERIAL EEPROM: Internally organized with 64 pages of 16 bytes each, the 8K requires a 10-bit data word address for random word addressing.

・

AT24C16, 16K SERIAL EEPROM: Internally organized with 128 pages of 16 bytes each, the 16K requires an 11-bit data word address for random word addressing.

6) Block Diagram

Fig. 15 Block diagram

7) Refer to Table 16 about Functions and Data of the IC’s Pins.

35

SERVICE MANUAL

5. SWITCH-MODE POWER SUPPLY IC STRG5653/G8656

1) General Description

The STRG5653/G8656 are part of the STRG5600/G8600 series thick-film ICs for switch-mode power supply incorporating power MOSFET with a high-precise error amplifier. The ICs feature fewer external components, small-size and standard power supply.

The series STR-G8600 use Chip on Chip technology with the same operation principle as

STR-G5600. Pin configuration, function and threshold of STR-G8600 are compatible with those of STR-G5600.

2) Block Diagram

Fig.16 Block diagram

3) Function of Terminal

Table 11

Terminal No. Symbols

1 D

2 S

Description

Drain Terminal

Source Terminal

Functions

MOS FET drain

MOS FET source

4 VIN Power supply Terminal

Ground

Input of power supply for control signals

Input of overcurrent detection signal and constant voltage signals

4) Refer to Table 17 about Functions and Data of the IC’s Pins.

36

SERVICE MANUAL

6. TC90L01N

AUDIO/VIDEO SWITCHING IC FOR TVs

The TC90L01N is an audio/video switching

IC for TV sets. Conforming to I

2

C bus standards, it allows you to perform various switching operations through the bus lines by using a microcomputer. This IC has the functions of audio mute, ALC (Auto Level

Control), audio volume and so on.

Fig. 17

1) Features

·I

2

C bus control

·Video: 3-channel inputs and 1-channel outputs (1 channels conforming to S system)

·Audio: 3-channel inputs and 3-channel outputs

·Monitor Audio out

·ALC (Auto Level Control)

·Audio volume by attenuator circuit

·Audio mute

·2 I/O ports

37

SERVICE MANUAL

2). Block Diagram

V1 -V /Y in

V2 -V in

TV -V in

4

8

2

V1 -C in 6

S

ALC

10

V1 -L in

V2 -L in

TV -V in

5

9

1

V1 -R in

V2 -R in

TV -R in

7

11

3

18

+

20

ALC

I

2

L

Logic

I

2

C

BUS

I/O

14

13

19

21

Volume

Volume

V

CC

GND

12

15

22

17

24

16

23

V CC

GND

V out

Y out

C out

SCL

SDA

I/O-1

I/O-2

TV -L out

Mon-L out

TV -R out

Mon-R out

Fig. 18 Block diagram

38

SERVICE MANUAL

3) Pin Assignment

Fig.19 Pin assignment

39

4) Pin Description

Pin No. Name

SERVICE MANUAL

Function

Table 12

This pin is for input a left audio signal from the main demodulator in the TV set. The signal fed into this pin is

The input dynamic range of this pin is 6.0 Vp-p and the input resistance is 120 k.

This pin is for input a composite audio signal from the main demodulator in the TV set. The signal fed into this pin is

The input dynamic range of this pin is 2.0 Vp-p and the input resistance is 30 k.

This pin is for input a right audio signal from the main demodulator in the TV set. The signal fed into this pin is

The input dynamic range of this pin is 6.0 Vp-p and the input resistance is 120 k.

This pin is for input a luminance signal or composite video signal from an external source (V1 channel). The signal fed into

The input dynamic range of this pin is 2.0 Vp-p and the input resistance is 30 k .

This pin is for input a left audio signal from an external source

(V1 channel). The signal fed into this pin is presented to TV-L

The input dynamic range of this pin is 6.0 Vp-p and the input resistance is 120k.

This pin is for input a chroma signal from an external source

(S1 channel). The signal fed into this pin is presented to C out signal.

The input dynamic range of this pin is 2.0 Vp-p and the input

(continued)

40

10 ALC

SERVICE MANUAL resistance is 30 k.

This pin is for input a right audio signal from an external source

(V1 channel). The signal fed into this pin is presented to TV-R

The input dynamic range of this pin is 6.0 Vp-p and the input resistance is 120 k.

This pin is for input a composite video signal from an external source (V2 channel). The signal fed into this pin is presented to

The input dynamic range of this pin is 2.0 Vp-p and the input resistance is 30 k.

This pin is for input a left audio signal from an external source

(V2 channel). The signal fed into this pin is presented to TV-L

The input dynamic range of this pin is 6.0 Vp-p and the input resistance is 120.

This is an detect output pin of ALC[:Auto Level Control]. It controls ALC.

This pin is for input a right audio signal from an external source

(V2 channel). The signal fed into this pin is presented to TV-R

The input dynamic range of this pin is 6.0 Vp-p and the input consumption of this pin is 32 mA.

This is an I

2

C bus data input/output pin. The input threshold

Make sure that the current flowing into this pin is 3.0 mA or less.

This is an I

2

C bus data input/output pin. The input threshold level of this pin is 3.0 V.

16 TV-R

This pin is for output right audio signal. The signal fed into TV-R in, V1-R in, or V2-R in is outputted from this pin.

(continued)

41

SERVICE MANUAL

This outputted can be muted independently of TV-L out by bus control.

This pin is for output left audio signal. The signal fed into TV-L

17 TV-L in, V1-L in, or V2-L in is outputted from this pin.

This output can be muted independently of TV-R out by bus control.

18 Y

This pin is for output a luminance signal. The signal fed into

V1-V/Y in, V2-V in, or TV-V in is outputted from this pin.

This is an ADC input/DAC output pin. The ADC is a 2-level

19 I/O－１ detection type

(1 bits). The threshold level is 3.0 V. The DAC (1 bit) is an open-drain output. Make sure that the current flowing into this pin is 2.0 mA or less.

20 C

This pin is for output a chroma signal. The signal fed into V1-C out in, V1-V in, V2-V in , or TV-V in is outputted from this pin.

21 I/O－２

This is an ADC input/DAC output pin. The ADC is a 2-level detection type (1 bits). The threshold level is 3.0 V.

The DAC (1 bit) is an open-drain output. Make sure that the current flowing into this pin is 2.0 mA or less.

This pin is for output the main channel composite video signal.

22 V

The signal fed into TV-V in, V1-V in, V2-V in, or V1-Y in +_V1-C out in is outputted from this pin.

This output can be muted by bus control.

This pin is for monitor-output right audio signal. The signals fed into the chip via V1-R in, V2-R in, or TV-R in is output from this

23 Mon-R pin.

This output can be muted in combination with Mon-L out by bus control.

This pin is for monitor-output left audio signal. The signals fed into the chip via V1-L in, V2-L in, or TV-L in is output from this

24 Mon-L pin.

This output can be muted in combination with Mon-R out by bus control.

(continued)

42

SERVICE MANUAL

SERVICE DATA OF KEY ICS

Table 13 Functions and Service Data of TMPA8827PSGN (N210)’s Pins

1 2 3 4 5 6 7 8

Voltage（V） 4.9 4.9 5 0 5 2.22 2 0

Resistance(KΩ)

Voltage（V）

8.8 8.8 22 0 4.55 22.8 22.7 0

9 10 11 12 13 14 15 16

5 0 0 1.22 1.87 6.63 4.16 5

Resistance(KΩ)

17 18 19 20 21 22 23 24

Voltage（V）

Resistance(KΩ)

Voltage（V）

Resistance(KΩ)

Voltage（V）

10 26 26 26 26 0 26 26

25 26 27 28 29 30 31 32

3.4 1.9 4.85 5.4 8.84 3.1 0 3.8

10.3 26 24.2 22.9 0.39 3.32 3.3 2.9

33 34 35 36 37 38 39 40

2.97 2.44 2.49 4.96 2.2 4.39 1.8 0

Resistance(KΩ)

Voltage（V）

Resistance(KΩ)

26 24.8 26 1.6 20 22.8 26 0

41 42 43 44 45 46 47 48

1.6 1.6 2.4 4.9 2.5 3.3 2.4 0

49 50 51 52 53 54 55 56

Voltage（V）

Resistance(KΩ)

57 58 59 60 61 62 63 64

Voltage（V）

Resistance(KΩ) 13.7 13.7 12 22.6 13.5 20.4 6.6 6.7

43

SERVICE MANUAL

Pin

No.

Table 14 Functions and Service Data of TDA8944J (N603)’s Pins

Digital Multimeter

Functions Description

Reference Voltage Positive Resistance Negative Resistance

1 Negative loudspeaker terminal 1

2 Ground channel 1

(V)

7.98

0

(20KΩ)

∞

0

(20KΩ)

∞

0

3 Supply voltage channel 1

4 Positive loudspeaker terminal 1

6 Positive input 1

14.9

7.3

0

7.3

0

7.4

7.3

∞

∞

∞

∞

5.8

∞

∞

∞

∞

∞

∞

7.7

∞

∞

8 Negative input 1

9 Negative input 2

10

Mode selection input (standby, mute, operating)

11

Half supply voltage decoupling

(ripple rejection)

12 Positive input 2

0 7.8 8.9

7.6

∞ ∞

14 Negative loudspeaker terminal 2

15 Ground channel 2

16 Supply voltage channel 2

17 Positive loudspeaker terminal 2

7.3

0

7.3

0

14.8

7.3

∞

∞

∞

0

3.5

∞

∞

∞

∞

0

3.5

∞

Pin No.

Table 15 Functions and Service Data of LA78040/78041 (N301)’s Pins

GDM8145 Multimeter

Function Description

Ground Resistance (KΩ)

Voltage of

Pin (V)

Measure with red probe while grounding black probe.

Measure with black probe while grounding red probe.

0 0 0 1

Ground

2

Vertical output terminal

3 Pump supply voltage input

9.73 0.58 0.58

24.88

∞

∞

(continued)

44

SERVICE MANUAL

4 In-phase input terminal

5 Inverting input terminal

6 Supply voltage

7

Pump supply voltage output/vertical flyback pulse output

2.22 1.30 1.30

2.22 4.58 4.55

24.13 1.55 1.55

2.61 7.09 5.93

Pin

No.

7

Table 16 Functions and Service Data of AT24C16 (N230)’s Pins

Function Description

Reference Voltage

(V)

0

0

Digital Multimeter

Positive

Resistance (20KΩ)

0.001

Negative Resistance

(20KΩ)

0.00

0.001 0.00

PW write protect

0

0

5

4.99

4.99

5

0.001

0.001

7

6.9

9.5

3.5

0.00

0.00

4.83

5.15

5.31

3.25

Pin

No.

Table 17 Functions and Service Data of STR-G8656 (N801)’s Pins

Digital Multimeter

Functions Description

Reference Voltage

(V)

146.3

4 Power supply terminal

0

0

31.96

Positive Resistance

(20KΩ)

∞

0

0

∞

Negative Resistance

(20KΩ)

∞

0

0

∞

5

Overcurrent/Freedback terminal

1.72 0.699 0.166

45

SERVICE MANUAL

REPLACEMENT OF PARTS

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.

Description of the special markings:

A:

The components identified by the A marking have special safety-related characteristics.

AE

: The components identified by the AE marking are listed by EMC and have special safety-related characteristics.

CB

: The components identified by the CB marking have been evaluated to the CB standard.

E:

The components identified by the E marking are listed by EMC

G

: The components identified by the G marking have critical characteristics.

Z:

The components identified by the Z marking have important characteristics.

46

APPENDIX:

CIRCUIT DIAGRAM (1)

JUC7.820.1117

SIDE AV B OARD

8.5

JUC7.820.1151

JUC7.820.1014

CIRCUIT DIAGRAM (2)

CRT RGB

11

22

2. Check and make sure that all control buttons can work flexibly and normally.

3. Connect wires according to the final wiring diagram and check if the

33

FINAL ASSEMBLY DIAGRAM FOR 29CT24FS, 29CT71FS

10

(X4)

13

(X4)

55

44

560m m

66

77

AA

14

11

17

16

15

14

13

12

99

88

77

66

44

55

33

22

11

Wire clip B

Plasticine

11

11

11

11

11

11

11

11

11

44

66

11

44

44

+ + - -

Bal ck

44

FINAL WIRING DIAGRAM FOR 29CT24FS, 29CT71FS

B B

0

2 1

6 0 al al c k kc

+ + - -

BB

MAIN

PRINTED CIRCUIT BOARD DIAGRAMS

CRT RGB PRINTED CIRCUIT BOARD

AV PRINTED CIRCUIT BOARD

POWER PRINTED CIRCUIT BOARD

PARTS ON SOFT SWITCH PRINTED CIRCUIT BOARD

SIDE AV PRINTED CIRCUIT BOARD

REMOTE SENSOR AND INDICATOR PRINTED CIRCUIT BOARD