Toshiba 38VL14G User manual

TOSHIBA CORPORATION
1-1, SHIBAURA 1-CHOME, MINATO-KU, TOKYO 105-8001, JAPAN
PRINTED IN JAPAN May., 2001 T
FILE NO. 010-200102
SERVICE MANUAL
COLOUR TELEVISION
F0LP Chassis
38VL14G

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GENERAL ADJUSTMENTSSPECIFIC INFORMATIONS
TABLE OF CONTENTS
CHAPTER 1 GENERAL ADJUSTMENTS
SAFETY INSTRUCTIONS........................................................................................................................................3
SERVICE MODE ......................................................................................................................................................4
DESIGN MODE ........................................................................................................................................................7
ELECTRICALADJUSTMENTS ................................................................................................................................8
SCREEN AND MIRROR ALIGNMENTS ................................................................................................................13
CHAPTER 2 SPECIFIC INFORMATIONS
SETTING & ADJUSTING DATA ..............................................................................................................................14
LOCATION OF CONTROLS...................................................................................................................................15
PROGRAMMING CHANNEL MEMORY.................................................................................................................17
CIRCUIT BLOCK DIAGRAM ..................................................................................................................................19
MECHANICAL DISASSEMBLY ..............................................................................................................................21
CHASSIS AND CABINET REPLACEMENT PARTS LIST......................................................................................23
PC BOARDS LAYOUT TOPVIEW..........................................................................................................................45
PC BOARDS BOTTOMVIEW.................................................................................................................................47
TERMINAL VIEW OF TRANSISTORS ...................................................................................................................54
SPECIFICATIONS ..................................................................................................................................................57
APPENDIX:
CIRCUIT DIAGRAM

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GENERAL ADJUSTMENTSSPECIFIC INFORMATIONS
CHAPTER 1 GENERAL ADJUSTMENTS
SAFETY INSTRUCTIONS
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. When replacing a chassis in the cabinet, always be certain that all the protective devices are put back in place, such as; non-
metallic control knobs, insulating covers, shields, isolation resistor-capacitor network etc.
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 char-
acteristics 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 or other hazards.
LAMP REPLACEMENT CAUTION
When replacing the lamp of LCD projection TV, use Lamp Module Kit.
Be sure to read the caution in the instruction manual before replacing.

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GENERAL ADJUSTMENTSSPECIFIC INFORMATIONS
SERVICE MODE
1. ENTERING TO SERVICE MODE
S
(Service mode display)
Item
Data
3) While pressing the obutton,
press MENU button on TV set.
2) Press obutton again to
keep pressing.
2. DISPLAYING THE ADJUSTMENT MENU
1) Press MENU button on TV.
3. KEY FUNCTION IN THE SERVICE MODE
The following key entry during display of adjustment menu provides special functions.
Frequency of lamp replacement CALL + RGB button
Test signal selection : abutton (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)
“CSBRT” selection : 1 button
“SCNT” selection : 4 button
“COLP” (or “OTHER”) selection : 5 button
“TNTC” (or “TNTV”) selection : 6 button
Self diagnostic display ON/OFF : 9 button ............. note: Displayeddifferentlyasshownbelow,dependingonthe
setting of the receiving color system.
COLP (PAL)
COLC (NTSC)
COLS (SECAM)
1) Press obutton once on
Remote Control.
Adjustment mode
Press
Press
Service mode
Item
Data
S
CAUTION : Never try to perform initialization unless you have changed the memory IC.

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GENERAL ADJUSTMENTSSPECIFIC INFORMATIONS
4. SELECTINGTHE ADJUSTING ITEMS
1) Every pressing of CHANNEL sbutton in the service mode changes the adjustment items in the order of table-2.
(tbutton for reverse order)
Refer to table-2 for preset data of adjustment mode.
(See SETTING & ADJUSTING DATA on page 14)
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 CHANNELsbutton 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 abutton on the Remote Control changes the built-in test patterns on screen as described below
in SERVICE MODE.
Signals Picture
• Red raster
• Green raster
• Blue raster
• All Black
• All White
• Black & White
• Black cross-hatch
• White cross-hatch
• Black cross-dot
• White cross-dot
• Black cross-bar
• White cross-bar
• Black cross-bar
on green raster
• H signal (white)
• H signal (black)
*The signals marked with are not usable to display in theTest signal for some model.
Signal off NTSC signals (14 patterns)
PAL signals (14 patterns)

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GENERAL ADJUSTMENTSSPECIFIC INFORMATIONS
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.
23******
TIME : 000000
LAMP : 0000 00
BUS LINE : OK
BUS CONT : OK
BLOCK : UV V1 V2
QV01


<SELF CHECK>
Part number of microcomputer (QA01)
Toral hour of turn the TV on.
(unit: H, Max. 999999 hours)
Showing the operation hour of lamp.
(unit H, Max. 9999 hours)
LAMP : 0000 00
Frequency of lamp replacement.
(0~99)
Showing a count 1 by “CALL + RGB” button in “Serv-
ice mode.”
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.
Whenindication shows “Q uuu NG”, the devicewith
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.
Indicated color of mode now selected : Green and Red
Indicated color of other modes : Blue
Green :Normal
Red : Themicrocomputeroperatestoprovidejudgement
of no video signal. The red color is still indicated
thoughthe signal is input, failure may exist in input
signal line including QV01.
QV01 : In case of indication green ---Normal
In case of indication red with input signal----
Failure may exist in output line including QV01.
NOTE: (1)In case that power indicator is blinking with in-
terval of 1 second; A part of Bus line does not
operate normally.Check Bus line.

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GENERAL ADJUSTMENTSSPECIFIC INFORMATIONS
DESIGN MODE
1. ENTERING TO DESIGN MODE
ITEM
DATA
S D Press
(Design mode) (Adjustment mode)
Press
3) Press MENU button on TV.
2) While pressing CALL button on Remote
and press MENU button on TV.
1) Select the Service mode.
2. SELECTINGTHE ADJUSTING ITEMS
Every pressing of CHANNEL tbutton in the design mode changes the adjustment items in the order of table-3.
(sbutton for reverse order)
Refer to table-3 for data of design mode.
(See SETTING & ADJUSTING DATA on page 14)
3. ADJUSTINGTHE DATA
Pressing of VOLUME sor tbutton will change the value of data.
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”.

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GENERAL ADJUSTMENTSSPECIFIC INFORMATIONS
ELECTRICAL ADJUSTMENTS
(Reference factory adjustment)
F0LP Series Completing adjustment
Adjustment Input Point Adjusting Adjusting Conditions and Procesures
Items Output Point
Signal
Vertical phase (VPOS) Horizontal phase (HPOS) Bright adjustment (CSBRT) and white balance adjustment RDRV BDRV Sub-light adjust- ment (BRTC)
Visual adjustment by patterns (BUS control) Visual adjustment by patterns (BUS control) W/B checker (CA110) (Set condition: dy- namic) Visual adjustment by patterns (Set condition: dy- namic)
WG Phillips Pattern Sub Bright (NTSC) signal Do not use Phillips Pattern of FRANCE SECAM WG Phillips pattern Do not use Phillips Pattern of FRANCE SECAM CSBRT Adjusting signals (100% all white signals) 501RE W/B adjusting signals Sub-bright signals (J2ch)
Adjust by SUB address VPOS so that the up and down positions of the circle on Phillips Pattern will come to the center. Adjust by SUB address HPOS so that the left and right vertical bars of Phillips Pattern will look equal. Connect the CSBRT adjusting signals to the video input. Install the W/B checker on the screen. Select CSBRT at adjusting mode.
(The CSBRT data is changed to 52 from the initial value by a microcomputer, and both screen brightness will turn to MAX.)— To be dealt with by the production line
Adjust the CSBRT data so that the brightness at the time turns to (Normally White) x A%.
(When the data is adjusted, the SCBRT data returns to the initial value and screen brightness declines) A = 70±5 %
Connect the 501RE white signals to the video input and adjust by RDRV and BDRV so that they
will come to the following values. x = 0.280±0.005
y = 0.330±0.005
As shown in again, repeat after adjusting the CSBRT data.
Select BRTC at adjusting mode. Visually checked number of collapsed black lines :4±1.5 lines

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GENERAL ADJUSTMENTSSPECIFIC INFORMATIONS
Adjustment Input Point Adjusting Adjusting Conditions and Procesures
Items Output Point
Signal
Ghost adjustment (GHST) Flicker adjustment (FLCK)
Visual adjustment by patterns (BUS control) (Set condition: ) Visual adjustment by patterns (BUS control) (Set condition: )
Crosshatch signal (E4ch) Retma signal (E7ch)
Set to GHST adjusting mode.
Adjust by moving the data up and down so that the ghost will not appear on the left or right of the
screen’s vertical line.
* The ghost mentioned here is defined as the shadow that appears on the left or right of the 6th
pixel of image signal on the screen.(See illustration below)
Set to FLCK adjusting mode.
Move the FLCK data up and down to minimize the flicker while viewing the screen.
Ghost image (when the ghost appeared on the right)
Signal Ghost

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GENERAL ADJUSTMENTSSPECIFIC INFORMATIONS
Unit adjustment
Items Names Settings Input signals Measuring points
Measuring
Adjusting conditions and Adjusting standards
instruments
procedures
Contrast: MAX Bright: CNT Color: CNT * Selectable picture:
Dynamic
Contrast: MAX Bright: CNT Color: CNT * Selectable picture:
Dynamic
Contrast: MAX Bright: CNT Color: CNT * Selectable picture:
Dynamic
Sub-bright signal (J2ch) PAL sub-bright signal (UK23ch) SECAM color bar (E2ch)
TP46B TP46B TP46B
Select SCNT and adjust the
amplitude from the pedestal level to the white peak.
Select COLP. Adjust the amplitude of color bar’s
part. (P-P value of upper half)
Select COLS. Adjust the amplitude of color bar’s
part. (P-P value of upper half)
2.0 ±0.1 V (p-p)
0.9±0.1V (p-p)
* P-P value of
upper half
1.3±0.1V (p-p)
* P-P value of
upper half
[SCNT] [COLP] [COLS]
Sub-contrast Sub-color center PAL Sub-color center SECAM
Synchro Synchro Synchro