Sanyo CE28C7A Schematic

Part No. SKSM0681 C5WGL/S OCTOBER 2003

Colour Television Service Manual

Model CE28C7A-C

Service Ref. No. CE28C7A-C-00

CE28C7A-C-01

PRODUCT CODE: 111361006 ORIGINAL VERSION: Chassis No. EB7-B

Give complete "SERVICE REF. NO." for parts order or servicing, it is shown on the rating sheet on the cabinet back of the TV set.

Note This TV receiver will not work properly in foreign countries where the television transmission system and power source differ from the design specifications. Refer to the specifications for the design specifications

CE28C7A-C

Contents

Safety precautions/Specifications ..................................................................................................................2

Block diagrams ..............................................................................................................................................3

Cabinet Disassembly......................................................................................................................................4

Adjustment and Repair Procedures............................................................................................................5~9

CPU Functions ..............................................................................................................................................................................10~1 1

Component Locations ............................................................................................................................12~13

IC Block Diagrams..................................................................................................................................14~18

Pin description of semiconductors................................................................................................................19

Part Description and reading of schematic diagram ....................................................................................20

Cabinet Parts List ........................................................................................................................................21

Electric Parts List....................................................................................................................................22~26

Please use Schematic Diagram SKP20415 with this Service Manual.

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C5WGL/S

BLOCK DIAGRAM

This is a diagram for all models and therefore differs slightly from the actual block diagram.

Outline

AERIAL

IC3451

NICAM/

60 61

IF

A101

TUNER

X132

STEREO

12

5 4

IF-IN

80

26

71

SIF-OUT

SCL

SDA

SCL

K1001

SCART SC1

79

SDA SCL

X131

SIF-IN

19

IC1201

76

75

20

Video-IN

R/G/B-IN

Video/Y-Out

9816

AV-VIDEO-SW <LA7954>

Video-Out

48

54

IC201

IF/VIDEO/CHROMA/DEF

22

27

SDA

20

23

21

11/7/15

15

C-IN

46

33

EW-OUT

SCART SC2

20

Y-IN

Video/

Y-IN

C-IN

58

47

V-OUT

K1002

C-OUT

61

39

H-OUT

19

M-OUT R

51/53

R

Q462

15

C-IN

R/G/B-IN

2/5/12

1/3/13

12

13

4

14

G

B

575655

121314

B

G

Q461

7/11/15

15

IC1401

RGB-SW

L461

L462

6

R/G/B-OUT

3

TUBE

PICTURE

B

R

G

Q701

Q721

Q711

T451 FLYBACK

CRT

HEATER

Q432

H-OUTPUT

Q431

H.V

FOCUS/SCREEN

200V

D.Y

A1901

1 5

8/10

MUTE

CPU

IC801

RC RECEIVER

1

RC-IN

KEY SW

IC001

AUDIO-OUT

BLK

45

181716

8

KEY-IN

SDA

C BUS

2

I

R

G

SCL

CONTROL

B

H-BLANK

4

15

19

SDA

IC803

MEMORY

20

SCL

D441

IC501

V-OUTPUT

Q682

Q685

Q686

27V

145V

Reg.

Q651

25V

14

11

18

Q641

Q642

12

13

10

Q645

Q643

-27V

D646

D641

9V

IC642

WIDTH

SCREEN

CONTROL

POWER

D647

5V-1

IC643

Q661

15

D637

34

33

53

54

11

21

PROTECT

5V

Q666

IC641

T611

3

Q611

D615

CONVERTER

5

8

C607

2

Q613

SP902

SP901

SPEAKER

D603-D606

SW901

AC

C5WGL/S

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OPTION SETTING

[After replacing the Memory IC (IC803)]

The memory IC, IC803, stores the option data of TV set and service adjustments data for each circuit, therefore, when the memory IC is replaced, it should be performed following setting and “SERVICE ADJUSTMENT” on next page.

To enter to the Option Mode

+ Press and hold the F/OK button on the remote control and P▼ button on the front panel of the TV. The option

window will appear on the screen.

To set the option mode

+ Highlight the desired option item by using the P▲ or P▼ button . + To switch the option mode, use the Volume - (LEFT) or Volume + (RIGHT) button.

+ The data which is set in the option mode is stored into the memory IC automatically.

Following table shows the available option items and default setting mode.

Exit from the Service Mode

+ Press the RECALL button.

Option Mode Mode Description & Note

ON-TIMER ON or OFF On-timer available, default “ON” SORT MODE SORTING or Tuning mode, default “SORTING”

TUNING P & P ON or OFF Plug & Play mode, default “ON” WEL. TEXT ON or OFF Display message when first set up, default “ON” COMB FILTER OFF or ON For factory use, default “OFF” BBE ON or OFF BBE sound mode, default “OFF” AUTO VOLUME ON or OFF Default “OFF” HEADPHONE ON or OFF Headphone control , default “OFF” COUNTRY UK, IRE TV system, default “UK”

BG/DK / I / LL’ WIDE ON or OFF Wide mode, default ON AV3 ON or OFF Front AV3 mode, default OFF CS or A,B CS or A.B

OPTION MODE FOR CE28C7A-C-00/01

?

OPTION

ON-TIMER ON SORT MODE SORTING P&P ON WEL. TEXT ON COMB FIL TER OFF BBE OFF AUT O VOLUME OFF HEADPHONE OFF COUNTRY BG/DK/I/LL' WIDE OFF AV3 OFF CS / A,B CS

ADJUST : EXIT : RECALL

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C5WGL/S

SERVICE ADJUSTMENTS

[After replacing the Memory IC (IC803)]

The memory IC, IC803, stores the service adjustments data for each circuit, therefore, when the memory IC is replaced, it should be programmed by using “OPTION SETTING” on previous page and the following adjustments.

ADJUSTABLE SERVICE ADJUSTMENT

REGULAR

IMAGE

To enter to the Service Mode

+ Press and hold the GREEN button on the remote control and then press the P▼ button inside of the door. Press

the P▼ button to highlight the mode required (Regular, Image, others and TB12**). Then press the F/OK button to select the mode.

IMPORTANT NOTICE

Do not attempt to adjust service adjustments not listed on the above otherwise it may cause loss of performance and product safety.

Item No. OSD Description

1 P V-C P Vertical Position Adjustment 2 P H-P P Horizontal Position Adjustment 3 P V-L P Vertical Linearity Adjustment 4 P VSC P Vertical S-Correction Adjustment 5 P V-A P Vertical Size Adjustment 6 P H-S P Horizontal Size Adjustment 7 P E-P P Pin Cushion Adjustment 8 P E-T P Trapezoid Distortion Adjustment 11 P ECT P Top Corner Correction Adjustment 12 P ECB P Bottom Corner Correction Adjustment 13 P HPA P Parallelogram Distortion Adjustment

Item No. OSD Description

1 AGC AGC Adjustment 2 -- Cut-Off Drive Adjustment 3 GRY G-Drive Adjustment (white balance) 4 GRY B-Drive Adjustment (white balance) 5 CTR Contrast Adjustment (use factory setting)(for factory use) 6 -- Screen Adjustment mode 8 OSD OSD Positioning Adjustment

Note: Some items of the service adjustments for this chassis are controlled by the CPU, IC801, and the adjustments are carried out by using the RC handset.

The available adjustment items are as follows;

Image : This can be adjusted for picture images/shapes. Regular : This can be adjusted for the service adjustment. other : This is for factory setting. DO NOT ADJUST. TB1251 : This is for the factory setting. DO NOT ADJUST.

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C5WGL/S

To select the mode and service item and change data value

+ Highlight the desired adjustment mode by using the P▲ or P▼ button and then press the F/OK button. + To select the adjustment item, use the P▲ or P▼ button.

+ To change the service data, use the Volume -(LEFT) or Volume + (RIGHT) button. + The data which is set in the service mode is stored into the memory IC automatically.

Exit from the Service Mode

+ Press the RECALL button or turn off the TV set by using the Mains switch.

INITIALISATION OF MEMORY IC

To initialise the memory IC (IC803), press and hold the NORMAL button on the remote control, then press the P▼ button on the front panel of the TV set and then turn the Mains switch Off and On. The initialisation is now completed. When initialised the memory IC and all of the setting data (option data and service adjustment data) stored in the IC are reset to the default value. It is necessary to set the option settings and readjust the service adjustments listed on page 6 and to re-tune all the channels.

REGULAR mode

IMAGE mode

REGULAR 1, AGC 38

Adjustment No. and Item name

Adjustment Data

Adjustment No. and Item name

IMAGE

1. P V-P 1F

Adjustment Data

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C5WGL/S

ADJUSTMENTS

IMPORTANT NOTICE

Do not attempt to adjust the following service adjustments except when adjustments are required in servicing otherwise it may cause loss of performance and product safety.

1. Receive white raster pattern.

2. Set controls to normal.

3. Connect digital voltmetre to test point TP-B and GND.

4. Adjust voltage to 150 ±0.5V by using VR641.

1. Input and tune an RF signal which is UHF to the clearest station.

2. Connect digital voltmetre to test point TP-A and GND.

4. Enter to the service mode and select mode “REGU-

LAR”, and select item no.1 “REGULAR 1, AGC”.

5. Press the LEVEL+ or LEVEL - button to adjust volt-

age to be 3.2Vdc.

By using FOCUS VR, adjust focus control for well defined scanning lines.

SCREEN ADJUSTMENT

1. Receive black & white pattern.

2. Enter to the service mode and select mode “REGU-

LAR”, and select item no. 2 “REGULAR 2, CUT”. The horizontal line will appear on the screen.

3. Set the SCREEN VR for one colour to be just visible.

4. Using the numeric buttons shown set each colour to

minimum by decreasing to the point where any further decrease resets the adjustment to maximum value.

BIAS ADJUSTMENT

5. By using the buttons 1, 2, 4, 5, 7, 8 on the remote

control, adjust the line to be white.

The key allocation is as follows;

Button No. Operation

1 Increase Red 2 Decrease Red 4 Increase Green 5 Decrease Green 7 Increase Blue 8 Decrease Blue

DRIVE ADJUSTMENT

6. Select item no.3 “REGULAR 3, GRY” (G-Drive) or 4 “REGULAR 4, GRY” (B-Drive) and adjust both initially to 40.

7. Change data value of each item by using

LEVEL + or

LEVEL - button to obtain the proper white balance.

PCC ADJUSTMENT

1. Receive cross hatch pattern and set screen mode to

“FULL”.

2. Enter to the service mode and select mode “IMAGE”,

and select item no. 7 “IMAGE 7.P E-P”.

3. Press the LEVEL+ or LEVEL - button to adjust the vertical line to be straight.

TRAPEZOID ADJUSTMENT

1. Receive cross hatch pattern and set screen mode to

“FULL”.

2. Enter to the service mode and select mode “IMAGE”,

and select item no. 8 “IMAGE 8.P E-T”.

3. Press the LEVEL+ or LEVEL - button to correct the trapezum distortion of the vertical line.

PCC ADJUSTMENT

GREY SCALE ADJUSTMENT

FOCUS ADJUSTMENT

AGC ADJUSTMENT

+ B VOLTAGE ADJUSTMENT

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C5WGL/S

CORNER ADJUSTMENT

1. Receive cross hatch pattern and set screen mode to “FULL”.

2. Enter to the service mode and select mode “IMAGE”, and select item no. 11 “IMAGE 11.P ECT” for top corner adjustment OR item no. 12 “IMAGE 12.P ECB for bottom corner adjustment.

3. Press the LEVEL+ or LEVEL - button to correct the

distortion of the vertical line around the corners.

HORIZONTAL CENTRING ADJUSTMENT