Toshiba TV 21S23N Schematic

FILE NO: 050-200247

TOSHIBA

SERVICE MANUAL

COLOUR TELEVISION

21S23N

PRINTED IN UK. 2003 C

SERVICING NOTICES ON CHECKING

As for the places which need special attentions, they are indicated with the labels or seals on the cabinet, chassis and parts. Make sure to keep the indications and notices in the operation manual.

2. AVOID AN ELECTRIC SHOCK

There is a high voltage part inside. Avoid an electric shock while the electric current is flowing.

3. USE THE DESIGNATED PARTS

The parts in this equipment have the specific characters of incombustibility and withstand voltage for safety. Therefore, the part which is replaced should be used the part which has the same character. Especially as to the important parts for safety which is indicated in the circuit diagram or the table of parts as a mark, the designated parts must be used.

4. PUT PARTS AND WIRES IN THE ORIGINAL POSITION AFTER ASSEMBLING OR WIRING

There are parts which use the insulation material such as a tube or tape for safety, or which are assembled in the condition that these do not contact with the printed board. The inside wiring is designed not to get closer to the pyrogenic parts and high voltage parts. Therefore, put these parts in the original positions.

5. TAKE CARE TO DEAL WITH THE CATHODE-RAY TUBE

In the condition that an explosion-proof cathoderay tube is set in this equipment, safety is secured against implosion. However, when removing it or serving from backward, it is dangerous to give a shock. Take enough care to deal with it.

6. AVOID AN X-RAY1. KEEP THE NOTICES

Safety is secured against an X-ray by considering about the cathode-ray tube and the high voltage peripheral circuit, etc. Therefore, when repairing the high voltage peripheral circuit, use the designated parts and make sure not modify the circuit. Repairing except indicates causes rising of high voltage, and it emits an X-ray from the cathoderay tube.

PERFORM A SAFETY CHECK AFTER

7. SERVICING

Confirm that the screws, parts and wiring which were removed in order to service are put in the original positions, or whether there are the portions which are deteriorated around the serviced places serviced or not. Check the insulation between the antenna terminal or external metal and the AC cord plug blades. And be sure the safety of that.

(INSULATION CHECK PROCEDURE)

Unplug the plug from the AC outlet.

Remove the antenna terminal on TV and turn on the TV.

Insulation resistance between the cord plug terminals and the eternal exposure metal [Note 2] should be more than 1M ohm by using the 500V insulation resistance meter [Note 1].

If the insulation resistance is less than 1M ohm, the inspection repair should be required.

[Note 1]

If you have not the 500V insulation resistance meter, use a Tester.

[Note 2]

External exposure metal: Antenna terminal

Earphone jack

HOW TO ORDER PARTS

Please include the following informations when you order parts. (Particularly the VERSION LETTER.)

1. MODEL NUMBER and VERSION LETTER The MODEL NUMBER can be found on the back of each product and the VERSION LETTER can be

found at the end of the SERIAL NUMBER.

2. PART NO. and DESCRIPTION You can find it in your SERVICE MANUAL.

IMPORTANT

Inferior silicon grease can damage IC's and transistors. When replacing an IC's or transistors, use only specified silicon grease (YG6260M). Remove all old silicon before applying new silicon.

A1-1

CONTENTS

SERVICING NOTICES ON CHECKING......................................................................................................

HOW TO ORDER PARTS ...........................................................................................................................

IMPORTANT................................................................................................................................................

CONTENTS .................................................................................................................................................

GENERAL SPECIFICATIONS ....................................................................................................................

DISASSEMBLY INSTRUCTIONS

1.REMOVAL OF ANODE CAP ..............................................................................................................

2.REMOVAL AND INSTALLATION OF FLAT PACKAGE IC ...............................................................

SERVICE MODE LIST.................................................................................................................................

CONFIRMATION OF HOURS USED ..........................................................................................................

WHEN REPLACING EEPROM( MEMORY) IC ...........................................................................................

ELECTRICAL ADJUSTMENTS ..................................................................................................................

BLOCK DIAGRAM ......................................................................................................................................

PRINTED CIRCUIT BOARDS

MAIN/CRT...............................................................................................................................................

STEREO .................................................................................................................................................

SCHEMATIC DIAGRAMS

MICON/TUNER.......................................................................................................................................

IF/CHROMA............................................................................................................................................

21PIN ......................................................................................................................................................

DEFLECTION/CRT.................................................................................................................................

POWER ..................................................................................................................................................

SOUND AMP ..........................................................................................................................................

STEREO .................................................................................................................................................

WAVEFORMS .............................................................................................................................................

MECHANICAL EXPLODED VIEW ..............................................................................................................

MECHANICAL REPLACEMENT PARTS LIST ..........................................................................................

ELECTRICAL REPLACEMENT PARTS LIST ............................................................................................

A1-1 A1-1 A1-1 A2-1 A3-1~A3-5

B1-1 B2-1, B2-2 C-1 C-1 C-2 D-1~D-5 E-1, E-2

F-1~F-4 F-5, F-6

G-1, G-2 G-3, G-4 G-5, G-6 G-7, G-8 G-9, G-10 G-11, G-12 G-13, G-14 H-1~H-4 I-1 J1-1 J2-1~ J2-5

A2-1

GENERAL SPECIFICATIONS

G-1 TV CRT CRT Size / Visual Size 21 inch / 544.5mmV

G-2 Tuning Broadcasting System CCIR System B/G

G-3 Power Power Source AC 230V AC 50Hz

G-4 Regulation Safety CE(EN60065:98)

G-5 Temperature Operation +5oC ~ +40oC

G-6 Operating Humidity Less than 80% RH

System CRT Type NORMAL

Color System PAL/SECAM Speaker 2 Speaker

Sound Output MAX

DDR SECAM Yes NTSC3.58(AV)+NTSC4.43 Yes PAL60Hz Yes

System Tuner and System 1Tuner

Receive CH Destination Hyper

Intermediate Picture(FP) 38.9 MHz Frequency Sound(FS) 33.4 MHz

Preset CH 100 Stereo/Dual TV Sound Yes Tuner Sound Muting Yes

Power Consumption at AC

Protector Power Fuse Yes

Deflection 90 degree Magnetic Field BV/BH +0.45G/0.18G

Position Front Size Impedance 4 ohm

10%(Typical) 4.0+4.0 W

Tuning System F-Synth Input Impedance VHF/UHF 75 ohm

CH Coverage S11 - S41, E21 - E69

FP-FS 5.5MHz

Stand by (at AC) 3 W at AC 230 V 50 Hz Per Year -- kWh/Year

Radiation CE X-Radiation -

Storage -20oC ~ +60oC

2.0 x4.7 Inch

5.0+5.0 W

E2 - E4, X - Z+2, S1 - S10, E5 - E12,

B/G

60 W at AC 230 V 50 Hz

A3-1

GENERAL SPECIFICATIONS

G-7 On Screen Menu Yes

G-8 OSD Language English French Spanish

G-9 Clock and Sleep Timer Max Time - Min

Display Menu Type Character

Picture Yes

Contrast Yes Brightness Yes Color Yes Tint (NTSC Only) Yes Sharpness Yes

Audio Yes

Bass Yes Treble Yes Balance Yes BBE On/Off No Stable Sound On/Off No

CH Tuning Yes

Manual Yes Auto Yes

CH Allocation Yes Language Yes Clock Set No On Timer Set Yes Off Timer Set Yes Pin Code Registration No Panel Lock Yes Nicam Auto Off Yes AV Color System Yes Sound System No Auto 4:3 Default No AV2 Output Yes

Output Source Yes

Source Yes Control Level Yes

Volume Yes

Brightness Yes

Contrast Yes

Color Yes

Tint (NTSC Only) Yes

Sharpness Yes

Tuning Yes

Bass Yes

Treble Yes

Balance Yes

Back Light No Nicam ST Yes G(A2)Stereo Yes Tone 1/2 (A/B) Yes Surround On/Off No Pin Code No AV Yes Skip Yes Channel Yes Hotel Lock No Sleep Timer No Selectable Picture Yes Wide Mode No Sound Mute Yes

German Italian Greek Turkish Swedish Dutch Portuguese Norwegian Finnish Danish

Timer Step - Min

Clock No On Timer Program( On Timer) Yes Off Timer Program( Off Timer) Yes Wake Up Timer No Timer Back-up (at Power Off Mode) more than -- Min Sec

A3-2

GENERAL SPECIFICATIONS

G-10 Remote Unit RC-EY

Control Glow in Dark Remocon No

Format NEC Custom Code 40-BF h Power Source Voltage(D.C) 3V

UM size x pcs UM-4 x 2 pcs

Total Keys 33 Keys Keys Power Yes

1 Yes

2 Yes

3 Yes

4 Yes

5 Yes

6 Yes

7 Yes

8 Yes

9 Yes

0 Yes

Volume Up / + Yes

Volume Down / - Yes

Previous Yes

Select Picture Yes

Menu Yes

OK(Enter) Yes

EXIT No

Audio Select Yes

Sleep Timer No

Mute Yes

T'TEXT Keys TEXT / MIX / TV Yes

CH Up / Page Up Yes

CH Down / Page Down Yes

Red Yes

Green Yes

Yellow Yes

Cyan Yes

TEXT F/T/B Yes

Reveal Yes

TIMED PAGE(SUB PAGE) Yes

CALL / TEXT INDEX Yes

INPUT SELECT Yes

TEXT HOLD Yes

TIME / TXCL Yes

A3-3

GENERAL SPECIFICATIONS

G-11 Features Auto Degauss Yes

G-12 Accessories Owner's Manual Language English, Spanish, Portgal, Swedish,

Auto Shut Off Yes Canal+ No CATV No Anti-theft(Back Up 30 Min.) No Memory(Last CH) Yes Memory(Last Volume) Yes BBE No Auto Search Yes CH Allocation Yes Just Clock Function No Game Position No CH Label No VM Circuit No Full OSD No Unitext No Fastext Yes Top Text Yes Premiere No Comb Filter No

Auto CH Memory Yes Stable Sound No Auto Set Up No FBT Leak Test Protect Yes Previous (Quick View) Yes Panel Lock Yes Power On Memory Yes Double Focus & Dynamic Focus No Wss Signal Wide Change No Virtual Dolby Surround No Hotel Lock No

w/Guarantee Card

Remote Control Unit Yes Rod Antenna

Poles Pole

Terminal type

Loop Antenna

Terminal -

U/V Mixer DC Car Cord (Center+) Guarantee Card Warning Sheet Circuit Diagram Antenna Change Plug Service Facility List Important Safeguard Yes (Owner's Manual In) Dew/AHC Caution Sheet AC Plug Adapter Quick Set-up Sheet Yes Battery Yes

UM size x pcs UM-4 x 2 pcs

OEM Brand No

AC Cord AV Cord (2Pin-1Pin) Registration Card PTB Sheet 300 ohm to 75 ohm Antenna Adapter

Lines

Norwegian

No No No No No No No

No No

No No No No No

A3-4

GENERAL SPECIFICATIONS

/ 6 Surfaces

G-13 Interface Switch Front Power (Tact Sw) No

Rear AC/DC No

Indicator Power No

Terminals Front Video Input

Rear Video Input(Rear1)

G-14 Set Size Approx. W x D x H (mm) 590 x 492 x 446.5 G-15 Weight Net (Approx.) 21.0 kg

G-16 Carton Master Carton

Gift Box Yes

Drop Test

Container Stuffing 288

G-17 Cabinet Material Cabinet Front PS 94HB

System Select No

Main Power SW Yes

Sub Power No

Channel Up Yes

Channel Down Yes

Volume Up Yes

Volume Down Yes

TV/CATV Selector No

Degauss No

Main Power SW No

Stand-by No

Stand-by/ON Yes(Red)

On Timer Yes(Green)

Audio Input

Other Terminal

Video Input(Rear2)

Audio Input(Rear1)

Audio Input(Rear2)

Video Output

Audio Output

Euro Scart(21Pin) Yes ( x1 )

S-INPUT Yes ( x1 )

Euro Scart(21Pin) Yes ( x1 )

RGB-INPUT Yes ( x1 )

Component Input

Diversity No

Ext Speaker No

DC Jack 12V(Center +) No

VHF/UHF Antenna Input

AC Outlet No

Gross (Approx.) 23.8kg

Content ----

Material --

Dimensions W x D x H(mm) -- x -- x --

Description of Origin

Material Double/Brown

Dimensions W x D x H(mm) 658 x 575 x 529

Design As per Buyer's

Description of Origin

Height (cm) 46

Cabinet Rear PS 94HB

Holder PS 94V0 N

RCA RCA x2 Head Phone (Stereo)

D Type

---

Natural Dropping At 1 Corner / 3 Edges

No No No No No No

( --- lbs) ( ---lbs) No Sets /--

Sets/40' container

A3-5

DISASSEMBLY INSTRUCTIONS

1. REMOVAL OF ANODE CAP

Read the following NOTED items before starting work. *

After turning the power off there might still be a potential voltage that is very dangerous. When removing the Anode Cap, make sure to discharge the Anode Cap's potential voltage.

Do not use pliers to loosen or tighten the Anode Cap terminal, this may cause the spring to be damaged.

REMOVAL

1. Follow the steps as follows to discharge the Anode Cap.

(Refer to Fig. 1-1.)

Connect one end of an Alligator Clip to the metal part of a flat-blade screwdriver and the other end to ground. While holding the plastic part of the insulated Screwdriver, touch the support of the Anode with the tip of the Screwdriver. A cracking noise will be heard as the voltage is discharged.

GND on the CRT

3. After one side is removed, pull in the opposite direction to remove the other.

NOTE

Take care not to damage the Rubber Cap.

INSTALLATION

1. Clean the spot where the cap was located with a small amount of alcohol. (Refer to Fig. 1-3.)

Location of Anode Cap

Fig. 1-3

NOTE

Confirm that there is no dirt, dust, etc. at the spot where the cap was located.

2.3.Arrange the wire of the Anode Cap and make sure the wire is not twisted. Turn over the Rubber Cap. (Refer to Fig. 1-4.)

Screwdriver

Alligator Clip

GND on the CRT

Flip up the sides of the Rubber Cap in the direction of the

2. arrow and remove one side of the support.

(Refer to Fig. 1-2.)

Rubber Cap

CRT

Support

CRT

Fig. 1-1

Fig. 1-2

Fig. 1-4

4. Insert one end of the Anode Support into the anode button, then the other as shown in Fig. 1-5.

Support

CRT

5.6.Confirm that the Support is securely connected. Put on the Rubber Cap without moving any parts.

Fig. 1-5

B1-1

DISASSEMBLY INSTRUCTIONS

REMOVAL AND INSTALLATION OF FLAT PACKAGE IC

REMOVAL

Put the Masking Tape (cotton tape) around the Flat

1. Package IC to protect other parts from any damage.

(Refer to Fig. 2-1.) NOTE

Masking is carried out on all the parts located within 10 mm distance from IC leads.

When IC starts moving back and forth easily after

3. desoldering completely, pickup the corner of the IC using a tweezers and remove the IC by moving with the IC desoldering machine. (Refer to Fig. 2-3.)

NOTE

Some ICs on the PCB are affixed with glue, so be careful not to break or damage the foil of each IC leads or solder lands under the IC when removing it.

Blower type IC desoldering machine

Masking Tape (Cotton Tape)

Heat the IC leads using a blower type IC desoldering

machine. (Refer to Fig. 2-2.)

NOTE

Do not add the rotating and the back and forth directions force on the IC, until IC can move back and forth easily after desoldering the IC leads completely.

Blower type IC desoldering machine

Fig. 2-1

Tweezers

Peel off the Masking Tape.4. Absorb the solder left on the pattern using the Braided

5. Shield Wire. (Refer to Fig. 2-4.)

NOTE

Do not move the Braided Shield Wire in the vertical direction towards the IC pattern.

Fig. 2-3

Braided Shield Wire

Soldering Iron

Fig. 2-2

IC pattern

Fig. 2-4

B2-1

DISASSEMBLY INSTRUCTIONS

INSTALLATION

Take care of the polarity of new IC and then install the

1. new IC fitting on the printed circuit pattern. Then solder each lead on the diagonal positions of IC temporarily.

(Refer to Fig. 2-5.)

Soldering Iron

Solder temporarily

Supply the solder from the upper position of IC leads

Solder temporarily

sliding to the lower position of the IC leads. (Refer to Fig. 2-6.)

Fig. 2-5

When bridge-soldering between terminals and/or the

4. soldering amount are not enough, resolder using a Thintip Soldering Iron. (Refer to Fig. 2-8.)

Thin-tip Soldering Iron

Fig. 2-8

Finally, confirm the soldering status on four sides of the

5. IC using a magnifying glass. Confirm that no abnormality is found on the soldering position and installation position of the parts around the IC. If some abnormality is found, correct by resoldering.

NOTE

When the IC leads are bent during soldering and/or repairing, do not repair the bending of leads. If the bending of leads are repaired, the pattern may be damaged. So, be always sure to replace the IC in this case.

Soldering IronSolder

Absorb the solder left on the lead using the Braided

Supply soldering from upper position to lower position

Shield Wire. (Refer to Fig. 2-7.)

NOTE

Do not absorb the solder to excess.

Soldering Iron

Braided Shield Wire

Fig. 2-6

Fig. 2-7

B2-2

SERVICE MODE LIST

This unit provided with the following SERVICE MODES so you can repair, examine and adjust easily. To enter the Service Mode, press both set key and remote control key for more than 2 seconds.

Set Key

VOL. (-) MIN 0

VOL. (-) MIN

VOL. (-) MIN 8

VOL. (-) MIN

Remocon Key

Reset the user setting items (PICTURE, VOLUME, LANGUAGE and NICAM AUTO/ OFF) to the initial state for delivery.

Initialization of the factory.

NOTE:

POWER ON total hours is displayed on the screen. Refer to the "CONFIRMATION OF HOURS USED".

Can be checked of the INITIAL DATA of MEMORY IC. Refer to the "WHEN REPLACING EEPROM (MEMORY) IC".

Writing of EEPROM initial data. NOTE: Do not use this for the normal servicing.

Display of the Adjustment MENU on the screen. Refer to the "ELECTRICAL ADJUSTMENT" (On-Screen Display Adjustment).

Do not use this for the normal servicing. If you set a factory initialization, the memories are reset such as the channel setting, and the POWER ON total hours.

Operations

CONFIRMATION OF HOURS USED

POWER ON total hours can be checked on the screen. Total hours are displayed in 16 system of notation.

NOTE: If you set a factory initialization, the total hours is reset to "0".

Set the VOLUME to minimum.

Press both VOL. DOWN button on the set and Channel button (6) on the remote control for more than 2 seconds.

After the confirmation of using hours, turn off the power.

ADDRESS DATA

INIT 01 00 CRT ON 0010

FIG. 1

Initial setting content of MEMORY IC. POWER ON total hours.

= (16 x 16 x 16 x thousands digit value) + (16 x 16 x hundreds digit value) + (16 x tens digit value) + (ones digit value)

C-1

WHEN REPLACING EEPROM (MEMORY) IC

If a service repair is undertaken where it has been required to change the MEMORY IC, the following steps should be taken to ensure correct data settings while making reference to TABLE 1.

INI

+0 +1 +2 +3 +4 +5 +6 +7 +8 +9 +A +B +C +D +E +F

--- 00 38 23 18 71 80 48 00 47

00 33 05 03 00 06 73

10 80 80 80 3C 00 BA 06 9F10 00 33 80 00 02 1A 25 53 2D 6D C0 00 44 20 0A 0020 26 18 1E 00 DF CA 05 00 A7 7F 07 00 40 00 00 0030 95 00 00 00 00 00 00 0F 27 2B 2F 33 37 3B 3F 4040 23 41 42 43 44 45 46

47 49 4A 4B 4C 4D 4E 4F 5050 48 51 51 52 52 53 53 54 55 55 56 56 57 57 58 5860 54 59 59 5A 5A 5B 5B

5C 5D 5D 5E 5E 5F 5F 60 6070 5C 61 61 62 63 64 65

22 CD CF D3 D8 94 97 99 5280 25 54 56 57 59 5B 5D

5E --- --- --- --- --- --- --- ---90 5F --- --- --- --- --- ---

Table 1

1.2.Enter DATA SET mode by setting VOLUME to minimum. Press both VOL. DOWN button on the set and Channel button (6) on the remote control for more than 2 seconds. ADDRESS and DATA should appear as FIG 1.

ADDRESS DATA

INIT 01 00 CRT ON 0010

Fig. 1

ADDRESS is now selected and should "blink". Using the VOL. +/- button on the remote, step through the ADDRESS until required ADDRESS to be changed is reached.

Press OK to select DATA. When DATA is selected, it will "blink".

Again, step through the DATA using VOL. +/- button until required DATA value has been selected.

Pressing OK will take you back to ADDRESS for further selection if necessary.

Repeat steps 3 to 6 until all data has been checked.

When satisfied correct DATA has been entered, turn POWER off (return to STANDBY MODE) to finish DATA input.

After the data input, set to the initializing of shipping.

Turn POWER on.

10.

Press both VOL. DOWN button on the set and Channel button (1) on the remote control for more than 2 seconds.

11.

After the finishing of the initializing of shipping, the unit will turn off automatically.

The unit will now have the correct DATA for the new MEMORY IC.

C-2

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