Toshiba 21SZ5T1 Schematic

SERVICE MANUAL

Color Television

21SZ5E1

FILE NO. 060-200414

S3E Chassis

21SZ5ES1

21SZ5T1

Mar. 2004 (YC/X)

CHAPTER 1 GENERAL ADJUSTMENTS

SAFETY INSTRUCTIONS ........................................................................................................................................ 3

SET-UP ADJUSTMENT ............................................................................................................................................ 4

SERVICE MODE ...................................................................................................................................................... 6

DESIGN MODE ........................................................................................................................................................ 9

ELECTRICAL ADJUSTMENTS .............................................................................................................................. 10

CIRCUIT CHECK ....................................................................................................................................................12

CHAPTER 2 SPECIFIC INFORMATIONS

SETTING & ADJUSTING DATA .............................................................................................................................. 13

LOCATION OF CONTROLS ................................................................................................................................... 14

CHANNEL PRESET................................................................................................................................................ 15

CHASSIS AND CABINET REPLACEMENT PARTS LIST ......................................................................................17

PC BOARDS BOTTOM VIEW................................................................................................................................. 23

TERMINAL VIEW OF TRANSISTORS ................................................................................................................... 26

CIRCUIT BLOCK DIAGRAM .................................................................................................................................. 28

SPECIFICATIONS .............................................................................................................................................. END

APPENDIX:

CIRCUIT DIAGRAM

– 2 –

CHAPTER 1 GENERAL ADJUSTMENTS

SAFETY INSTRUCTIONS

WARNING: BEFORE SERVICING THIS CHASSIS, READ THE “X-RAY RADIATION PRECAUTION”, “SAFETY PRECAU-

TION” AND “PRODUCT SAFETY NOTICE” INSTRUCTIONS BELOW.

X-RAY RADIATION PRECAUTION

1. Excessive high voltage can produce potentially hazardous X-RAY RADIATION. To avoid such hazards, the high voltage must not be above the specified limit. The nominal value of the high voltage of this receiver is (A) kV at zero beam current (minimum brightness) under a (C) V AC power source. The high voltage must not, under any circumstances, exceed (B) kV.

Refer to table-1 for high voltage (A), (B) & AC voltage (C). (See SETTING & ADJUSTING DATA on page 13)

Each time a receiver requires servicing, the high voltage should be checked following the HIGH VOLTAGE CHECK procedure in this manual. It is recommended that the reading of the high voltage be recorded as a part of the service record. It is important to use an accurate and reliable high voltage meter.

SAFETY PRECAUTION

WARNING : Service should not be attempted by anyone unfamiliar with the necessary precautions on this receiver. The following are the necessary precautions to be observed before servicing this chassis.

1. An isolation transformer should be connected in the power line between the receiver and the AC line before any service is performed on the receiver.

2. Always discharge the picture tube anode to the CRT conductive coating before handling the picture tube. The picture tube is highly evacuated and if broken, glass fragments will be violently expelled. Use shatter proof goggles and keep picture tube away from the unprotected body while handling.

3. When replacing a chassis in the cabinet, always be certain that all the protective devices are put back in place, such as; nonmetallic control knobs, insulating covers, shields, isolation resistor-capacitor network etc.

2. The only source of X-RAY RADIATION in this TV receiver is the picture tube. For continued X-RAY RADIATION protection, the replacement tube must be exactly the same type tube as specified in the parts list.

3. Some part in this receiver have special safety-related characteristics for X-RAY RADIATION protection. For continued safety, parts replacement should be undertaken only after referring to the PRODUCT SAFETY NOTICE below.

GENERAL ADJUSTMENTS

SPECIFIC INFORMATIONS

PRODUCT SAFETY NOTICE

Many electrical and mechanical parts in this chassis have special safety-related characteristics. These characteristics are often passed unnoticed by a visual inspection and the protection afforded by them cannot necessarily be obtained by using replacement components rated for higher voltage, wattage, etc. Replacement parts which have these special safety characteristics are identified in this manual and its supplements; electrical components having such features are identified by the international hazard symbols on the schematic diagram and the parts list. Before replacing any of these components, read the parts list in this manual carefully. The use of substitute replacement parts which do not have the same safety characteristics as specified in the parts list may create shock, fire, X-ray radiation or other hazards.

– 3 –

WARNING: BEFORE SERVICING THIS CHASSIS, READ THE “X-RAY RADIATION PRECAUTION”, “SAFETY PRECAU- TION” AND “PRODUCT SAFETY NOTICE” ON PAGE 3 OF THIS MANUAL.

SET-UP ADJUSTMENT

■ The following adjustments should be made when a complete realignment is required or a new picture tube is installed. Perform the adjustments in order as follows :

1. Color Purity

2. Convergence

3. White Balance

Note: The PURITY/CONVERGENCE MAGNET assembly and rubber wedges need mechanical positioning.

Refer to figure 1.

GENERAL ADJUSTMENTS

COLOR PURITY ADJUSTMENT NOTE : Before attempting any purity adjustments, the receiver

1. Demagnetize the picture tube and cabinet using a degauss-

2. Set the brightness and contrast to maximum.

3. Use a green raster from among the built-in test signals.

4. Loosen the clamp screw holding the yoke and slide the

SPECIFIC INFORMATIONS

Mounting position of the purity magnet assembly should fit to same position as old one because slightly difference to the position depend on a kind of tube.

There are no adjustment of purity and convergence in some picture tube (Unified with purity magnet)

5. Remove the Rubber Wedges.

should be operated for at least fifteen minutes.

ing coil.

yoke backward or forward to provide vertical green belt (zone) in the picture screen.

6. Rotate and spread the tabs of the purity magnet (See figure 2.) around the neck of the picture tube until the green belt is in the center of the screen. At the same time, enter the raster vertically.

7. Slowly move the yoke forward or backward until a uniform green screen is obtained. Tighten the clamp screw of the yoke temporarily.

8. Check the purity of the red and blue raster.

GLASS CLOTH TAPES

DEFLECTION YOKE

29.1mm(28", 29") 25mm(25") 19mm(19", 20", 21") 14mm(13", 14")

PURITY/ CONVERGENCE MAGNET ASS'Y

Figure 1.

TEMPORARY MOUNTING

RUBBER WEDGE

ADHESIVE

DEFLECTION YOKE

– 4 –

CONVERGENCE ADJUSTMENTS

NOTE: Before attempting any convergence adjustments, the

receiver should be operated for at least fifteen minutes.

■ CENTER CONVERGENCE ADJUSTMENT

1. Use the cross-dot pattern from among the built-in test signals.

2. Set the brightness and contrast for well defined pattern.

3. Adjust two tabs of the 4-Pole Magnets to change the angle between them (See figure 2.) and superimpose red and blue vertical lines in the center area of the picture screen.

4. Turn the both tabs at the same time keeping the angle constant to superimpose red and blue horizontal lines at the center of the screen.

5. Adjust two tabs of 6-Pole Magnets to superimpose red/ blue line and green one. Adjusting the angle affects the vertical lines and rotating both magnets affects the horizontal lines.

6. Repeat adjustments 3, 4, 5 keeping in mind red, green and blue movement, because 4-Pole Magnets and 6-Pole Magnets have mutual interaction and make dot movement complex.

6-POLE

4-POLE

MAGNETS

ADJUST THE ANGLE (VERTICAL LINES)

■ CIRCUMFERENCE CONVERGENCE ADJUSTMENT

1. Loosen the clamping screw of deflection yoke slightly to allow the yoke to tilt.

2. Temporarily put a wedge as shown in figure 1. (Do not remove cover paper on adhesive part of the wedge.)

3. Tilt front of the deflection yoke up or down to obtain better convergence in circumference. (See figure 3.) Push the mounted wedge into the space between picture tube and the yoke to fix the yoke temporarily.

4. Put other wedge into bottom space and remove the cover paper to stick.

5. Tilt front of the yoke right or left to obtain better convergence in circumference. (See figure 3.)

6. Keep the yoke position and put another wedge in either upper space. Remove cover paper and stick the wedge on picture tube to fix the yoke.

7. Detach the temporarily mounted wedge and put it in another upper space. Stick it on picture tube to fix the yoke.

8. After fixing three wedges, recheck overall convergence. Tighten the screw firmly to fix the yoke and check the yoke is firm.

9. Stick three adhesive tapes on wedges as shown in figure

FIXED

GENERAL ADJUSTMENTS

ROTATE TWO TABS AT THE SAME TIME (HORIZONTAL LINES)

PURITY MAGNETS

CONVERGENCE MAGNET ASSEMBLY ADJUSTMENT OF MAGNETS

Figure 2.

BLU RED

BLU

RED

4-POLE MAGNETS MOVEMENT

BGR

R G B

RGB

RED/BLU

GRN

Center Convergence by Convergence Magnets

B G R

RED/BLU GRN

6-POLE MAGNETS MOVEMENT

B G R

BGR

RGB

R G B

SPECIFIC INFORMATIONS

INCLINE THE YOKE UP (OR DOWN)

Circumference Convergence by DEF Yoke

Figure 3. Dot Movement Pattern

INCLINE THE YOKE RIGHT (OR LEFT)

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1. ENTERING TO SERVICE MODE

1) Press o button once on

Remote Control.

SERVICE MODE

2) Press o button again to

keep pressing.

3) While pressing the o button,

press MENU button on TV set.

GENERAL ADJUSTMENTS

2. DISPLAYING THE ADJUSTMENT MENU

1) Press MENU button on TV.

Service mode

3. KEY FUNCTION IN THE SERVICE MODE

The following key entry during display of adjustment menu provides special functions.

SPECIFIC INFORMATIONS

A single horizontal line ON/OFF: - / - - button (on Remote) or a button (on TV) Test signal selection : a button (on Remote) Selection of the adjustment items : Channel s/t (on TV or Remote) Change of the data value : Volume ; +/– (on TV or Remote) Adjustment menu mode ON/OFF : MENU button (on TV) Initialization of the memory (QA02) : CALL + Channel button on TV (s) Reset the count of operating protect

circuit to “00”: CALL + Channel button on TV (t)

“RCUT” selection : 1 button “GCUT” selection : 2 button “BCUT” selection : 3 button “CNTX” (or “SCNT”) selection : 4 button “COLC” selection : 5 button “TNTC” selection : 6 button

Test audio signal ON/OFF (1kHz) : 8 button Self diagnostic display ON/OFF : 9 button

Press

Adjustment mode

Item

Data

(Service mode display)

Item

Data

Color thickness correction note: Displayed differently as shown below, de-

pending on the setting of the receiving color system. COLP (PAL) COLC (NTSC) COLS (SECAM)

CAUTION : Never try to perform initialization unless you have changed the memory IC.

– 6 –

4. SELECTING THE ADJUSTING ITEMS

1) Every pressing of CHANNEL s button in the service mode changes the adjustment items in the order of table-2. (t button for reverse order)

Refer to table-2 for preset data of adjustment mode. (See SETTING & ADJUSTING DATA on page 13)

5. ADJUSTING THE DATA

1) Pressing of VOLUME ; +/– button will change the value of data in the range from 00H to FFH. The variable

range depends on the adjusting item.

6. EXIT FROM SERVICE MODE

1) Pressing POWER button to turn off the TV once.

■ INITIALIZATION OF MEMORY DATA OF QA02

After replacing QA02, the following initialization is required.

1. Enter the service mode, then select any register item.

2. Press and hold the CALL button on the Remote, then press the CHANNEL s button on the TV. The initialization of QA02 has

been complated.

3. Check the picture carefully. If necessary, adjust any adjustment item above. Perform “Auto search Memory” on the owner’s manual.

CAUTION: Never attempt to initialize the data unless QA02 has been replaced.

7. TEST SIGNAL SELECTION

1) Every pressing of a button on the Remote Control changes the built-in test patterns on screen as described below

in SERVICE MODE.

GENERAL ADJUSTMENTS

Signal off

NTSC signals (14 patterns)

PAL signals (14 patterns)

Signals Picture

• Red raster

• Green raster

• Blue raster

• All Black

• All White

• Black & White

• Black cross-bar

• White cross-bar

• Black cross-bar

on green raster

• Black cross-hatch

• White cross-hatch

• Black cross-dot

• White cross-dot

SPECIFIC INFORMATIONS

• H signal (white)

• H signal (black)

The signals marked with are not usable to display in the Test signal for some model.

– 7 –

8. SELF DIAGNOSTIC FUNCTION

1) Press “9” button on Remote Control during display of adjustment menu in the service mode. The diagnosis will begin to check if interface among IC’s are executed properly.

2) During diagnosis, the following displays are shown.

Indicated color of mode now selected : Green and Red



23******



POWER : 00



BUS LINE : OK



BUS CONT : OK



BLOCK : UV V1 V2

Indicated color of other modes : White

Green : Normal Red : The microprocessor operates to provide judgement

of no video signal. The red color is still indicated though the signal is input, failure may exist in input signal line.

GENERAL ADJUSTMENTS

 Part number of microprocessor (Q100)  Operation number of protecting circuit ----“00” is nor-

mal. When indication is other than “00”, overcurrent apts to flow, and circuit parts may possibly be damaged.

 BUS LINE CHECK ----“OK” is normal.

“SDA1-GND” ------------- SDA-GND short circuit. “SCL1-GND” -------------- SCL-GND short circuit. “SCL1-SDA1” ------------- SCL-SDA short circuit.

 BUS CONT ----“OK” is normal.

When indication shows “Q uuu NG”, the device with

SPECIFIC INFORMATIONS

the number may possibly be damaged.

 BLOCK

UV : TV reception mode V1 : VIDEO 1 input mode (a1) V2 : VIDEO 2 input mode (a2)

The items marked with are not usable to display in the SELF DIAGNOSTIC FUNCTION for some model.

– 8 –

1. ENTERING TO DESIGN MODE

1) Select the Service mode.

DESIGN MODE

2) While pressing o (or CALL) button on

Remote and press MENU button on TV.

3) Press MENU button on TV.

S D

(Design mode) (Adjustment mode)

When QA02 is initialized, items “OPT0” and “OPT1” of DESIGN MODE are set to the data of the representative model of this chassis family. Therefore, because ON-SCREEN specification remains in the state of the representative of model. This model is required to reset the data of items “OPT0” and “OPT1”.

2. SELECTING THE ADJUSTING ITEMS

Every pressing of CHANNEL t button in the design mode changes the adjustment items in the order of table-3. (s button for reverse order)

Refer to table-3 for data of design mode. (See SETTING & ADJUSTING DATA on page 13)

3. ADJUSTING THE DATA

Pressing of VOLUME s or t button will change the value of data.

Press

ITEM

DATA

GENERAL ADJUSTMENTS

SPECIFIC INFORMATIONS

– 9 –

+ 19 hidden pages

Toshiba 21SZ5T1 Schematic

TABLE OF CONTENTS

CHAPTER 1 GENERAL ADJUSTMENTS

SAFETY INSTRUCTIONS

SET-UP ADJUSTMENT

SERVICE MODE

DESIGN MODE