Toshiba 34HFX83 User manual

FILE NO. 073-200312
SERVICE MANUAL
– SUMMARY –
N3WS Chassis
COLOR TELEVISION
PUBLISHED IN JAPAN, Jun., 2003 So
34HFX83
(TAC0321)
34HFX83 is the same as 34HF83 except for the parts tabled on back of this sheet.
Use this service manual together with the service manual of 34HF83 (File No. 070-200307).

REPLACEMENT PARTS LIST DIFFERENCES
Location
No. Part No. Description
A201 23532042 Cover, Front Cover Assy
A401S 23532044 Cover, Back Cover Service
A701A 23067345 Carton, Top Case
C903 24436221 CD, 220pF
C905 24436221 CD, 220pF
C907 24436221 CD, 220pF
C909 24679330 L, 33?F, ±20%, 250V
C913 24763102 L, 1000?F, ±20%, 16V
C914 24092398 CD, 0.1?F, +80%, -20%, 25V
C918 24092398 CD, 0.1?F, +80%, -20%, 25V
C919 24092398 CD, 0.1?F, +80%, -20%, 25V
C963 24436331 CD, 330pF
C964 24436331 CD, 330pF
C965 24436331 CD, 330pF
C970 24214102 CD, 1000pF, ±10%, 500V
D916 23357012 Diode, 1SS244
D917 23357012 Diode, 1SS244
D918 23357012 Diode, 1SS244
D919 23357012 Diode, 1SS244
D926 23357012 Diode, 1SS244
D927 23357012 Diode, 1SS244
D928 23357012 Diode, 1SS244
D929 23357012 Diode, 1SS244
D949 23357012 Diode, 1SS244
D950 23357012 Diode, 1SS244
D951 23357012 Diode, 1SS244
D952 23357012 Diode, 1SS244
G908 24366560 CF, 56 ohm
G914 23118859 Diode, 1SS133
G915 23118859 Diode, 1SS133
G923 24366560 CF, 56 ohm
G924 23118859 Diode, 1SS133
G925 23118859 Diode, 1SS133
G941 24366560 CF, 56 ohm
G947 23118859 Diode, 1SS133
G948 23118859 Diode, 1SS133
G951 24366102 CF, 1k ohm
G966 24366102 CF, 1k ohm
G9880 24366102 CF, 1k ohm
H002 23148043 Module, IF, US WOW
MSP3441G VDS, MVUS52
* L901 23289120 Coil, Peaking, TRF4120A
L902 23289689 Coil, Peaking, TRF46R8AF
L903 23289689 Coil, Peaking, TRF46R8AF
L904 23289689 Coil, Peaking, TRF46R8AF
L905 23289835 Coil, Peaking, TRF41R5AT
L906 23289835 Coil, Peaking, TRF41R5AT
L907 23289835 Coil, Peaking, TRF41R5AT
L908 23237987 Coil, Peaking, TRF4100A
L910 23103146 Coil (Ferrite Bead), T M2030AA
L916 23289120 Coil, Peaking, TRF4120A
L924 23289120 Coil, Peaking, TRF4120A
Q901 23205159 Transistor, 2SC3942
Q902 23205165 Transistor, 2SC3950
Q903 23205159 Transistor, 2SC3942
Q904 23205165 Transistor, 2SC3950
Q905 23205159 Transistor, 2SC3942
TOSHIBA CORPORATION
1-1, SHIBAURA 1-CHOME, MINATO-KU, TOKYO 105-8001, JAPAN
Location
No. Part No. Description
Q906 23205165 Transistor, 2SC3950
Q930 23205158 Transistor, 2SC3790
Q931 23205156 Transistor, 2SA1480
Q933 23205158 Transistor, 2SC3790
Q934 23205156 Transistor, 2SA1480
Q936 23205158 Transistor, 2SC3790
Q937 23205156 Transistor, 2SA1480
Q961 23114433 Transistor, 2SC1815-Y
R901 24552101 OMF, 100 ohm, 1/2W
R902 24552101 OMF, 100 ohm, 1/2W
R903 24552101 OMF, 100 ohm, 1/2W
R907 24366560 CF, 56 ohm
R913 24366560 CF, 56 ohm
R914 24366101 CF, 100 ohm
R915 24366150 CF, 15 ohm
R916 24366330 CF, 33 ohm
R917 24366271 CF, 270 ohm
R918 24366330 CF, 33 ohm
R921 24366101 CF, 100 ohm
R922 24366150 CF, 15 ohm
R924 24366330 CF, 33 ohm
R925 24366271 CF, 270 ohm
R928 24366101 CF, 100 ohm
R929 24366150 CF, 15 ohm
R930 24366330 CF, 33 ohm
R933 24545829 FR, 8.2 ohm, 1/4W
R937 24366271 CF, 270 ohm
R940 24366560 CF, 56 ohm
R942 24366222 CF, 2200 ohm
R943 24366222 CF, 2200 ohm
R944 24366222 CF, 2200 ohm
R945 24366330 CF, 33 ohm
R946 24366330 CF, 33 ohm
R952 24366222 CF, 2200 ohm
R953 24366222 CF, 2200 ohm
R954 24366222 CF, 2200 ohm
R958 24366101 CF, 100 ohm
R961 24568472 Cement, 4700 ohm, 7W
R962 24568472 Cement, 4700 ohm, 7W
R964 24568472 Cement, 4700 ohm, 7W
R965 24568472 Cement, 4700 ohm, 7W
R966 24366331 CF, 330 ohm
R977 24366681 CF, 680 ohm
R978 24568472 Cement, 4700 ohm, 7W
R979 24568472 Cement, 4700 ohm, 7W
R980 24552101 OMF, 100 ohm, 1/2W
R981 24552101 OMF, 100 ohm, 1/2W
R982 24552101 OMF, 100 ohm, 1/2W
R9180 24366220 CF, 22 ohm
R9240 24366220 CF, 22 ohm
R9300 24366220 CF, 22 ohm
*U001 23788935 SIGNAL Board, PD1086C
*U004 23788433 CRT-D/SVM Board, PD1089
Y101 23566019 Owner’s Manual, nglish/
French, 34HFX83
* Y160 23306504 Remote Hand Unit, CT-90164

FILE NO. 070-200307
SERVICE MANUAL
COLOR TELEVISION
N3WS Chassis
34HF83
PUBLISHED IN JAPAN. May. 2003 So
(TAC0322)

– 2 –
GENERAL ADJUSTMENTS
TABLE OF CONTENTS
CHAPTER 1 GENERAL ADJUSTMENTS
SAFETY INSTRUCTIONS ........................................................................................................................................ 3
SET-UP ADJUSTMENT ............................................................................................................................................ 4
SERVICE MODE ...................................................................................................................................................... 6
ELECTRICAL ADJUSTMENTS ................................................................................................................................ 9
CIRCUIT CHECKS ................................................................................................................................................. 11
CHAPTER 2 SPECIFIC INFORMATIONS
SETTING & ADJUSTING DATA .............................................................................................................................. 12
LOCATION OF CONTROLS ................................................................................................................................... 13
ADDING CHANNELS TO THE TV'S MEMORY ...................................................................................................... 15
CHASSIS AND CABINET REPLACEMENT PARTS LIST ......................................................................................16
PC BOARDS BOTTOM VIEW................................................................................................................................. 31
TERMINAL VIEW OF TRANSISTORS ................................................................................................................... 40
CIRCUIT BLOCK DIAGRAM .................................................................................................................................. 42
SPECIFICATIONS .............................................................................................................................................. END
APPENDIX:
CIRCUIT DIAGRAM

–3 –
GENERAL ADJUSTMENTS
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 volt-
age 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 120V AC
power source. The high voltage must not, under any cir-
cumstances, exceed (B) kV.
Refer to table-1 for high voltage (A), (B).
(See SETTING & ADJUSTING DATA on page 12)
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 read-
ing 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.
2. This receiver is equipped with a Fail Safe (FS) circuit which
prevents the receiver from producing an excessively high
voltage even if the B+ voltage increases abnormally. Each
time the receiver is serviced, the FS circuit must be checked
to determine that the circuit is properly functioning, follow-
ing the FS CIRCUIT CHECK procedure in this manual.
3. The only source of X-RAY RADIATION in this TV receiver
is the picture tube. For continued X-RAY RADIATION pro-
tection, the replacement tube must be exactly the same
type tube as specified in the parts list.
4. Some part in this receiver have special safety-related char-
acteristics for X-RAY RADIATION protection. For contin-
ued safety, parts replacement should be undertaken only
after referring to the PRODUCT SAFETY NOTICE below.
SAFETY PRECAUTION
Connect a 1500 ohm 10 watt resistor, paralleled by a 0.15
µF, AC type capacitor, between a known good earth ground
(water pipe, conduit, etc.) and the exposed metallic parts,
one at a time. Measure the AC voltage across the combi-
nation of 1500 ohm resistor and 0.15 µF capacitor. Re-
verse the AC plug at the AC outlet and repeat AC voltage
measurements for each exposed metallic part. Voltage
measured must not exceed 0.3 volts rms. This corresponds
to 0.2 milliamp. AC. Any value exceeding this limit consti-
tutes a potential shock hazard and must be corrected im-
mediately.
WARNING : Service should not be attempted by anyone unfa-
miliar with the necessary precautions on this receiver. The fol-
lowing 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 serv-
ice is performed on the receiver.
2. Always discharge the picture tube anode to the CRT con-
ductive coating before handling the picture tube. The pic-
ture tube is highly evacuated and if broken, glass frag-
ments will be violently expelled. Use shatter proof gog-
gles and keep picture tube away from the unprotected body
while handling.
3. When replacing a chassis in the cabinet, always be cer-
tain that all the protective devices are put back in place,
such as; non-metallic control knobs, insulating covers,
shields, isolation resistor-capacitor network etc.
4. Before returning the set to the customer, always perform
an AC leakage current check on the exposed metallic parts
of the cabinet, such as antennas, terminals, screwheads,
metal overlays, control shafts etc. to be sure the set is
safe to operate without danger of electrical shock. Plug
the AC line cord directly into a 120V AC outlet (do not use
a line isolation transformer during this check). Use an AC
voltmeter having 5000 ohms per volt or more sensitivity in
the following manner:
AC VOLTMETER
0.15µF
Good earth ground
such as a water
pipe, conduit, etc.
Place this probe on
each exposed
metallic part.
1500 ohm
10 watt
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 charac-
teristics 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.

–4 –
GENERAL ADJUSTMENTS
WARNING: BEFORE SERVICING THIS CHASSIS, READ THE “X-RAY RADIATION PRECAUTION”, “SAFETY PRECAU-
TION”AND “PRODUCT SAFETY NOTICE”ON PAGE 3 OF SERVICE MANUAL.
SET-UP ADJUSTMENT FOR FLAT TUBE
■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.
COLOR PURITY ADUSTMENT
(1)Let the screen face in the installing direction or toward the east (when it is to be moved), bring up the service mode
screen after demagnetizing (front, left, right, and top) with the degaussing coil, receive white signals by pressing the
[TV/VIDEO] button, and then the receiver should be operated for more than 40 minutes.
(2)Perform rough adjustment of the central convergence with the P/C magnet according to the adjustment item.
(3)Receive built-in green signals, loosen set screws on the deflection yoke, remove rubber wedges, and shift the deflection
yoke to toward front.
(4)Move alternately the two 2-pole magnets of the P/C magnets so that the green raster can come to the center of the
screen.
Figure 1.
(5)Receive built-in red and blue signals, check that there is no inclination of the single color raster toward one side, and if
each color tilts to a great extent, make adjustment with the 2-pole magnet so that the 3 colors will come to the center
evenly.
(6)Receive the green raster, shift the deflection yoke from a
foremost position (hitting against the picture tube) to a
backward position horizontally, stop the deflection yoke
at a position where it begins to become a green raster,
and perform accurate marking on the picture tube.
(7)Shift the deflection yoke further backward, and perform
accurate marking at a position where the green raster
begins to being luck.
(8)Fix the deflection yoke at a position 60% forward within
the range marked in items (6) and (7) above.
CONVERGENCE ADJUSTMENTS
* Adjust the convergence magnet to get vest convergence in the the order to (1) ~ (5).
■ CENTER CONVERGENCE:
(1)Receive the white crosshatch or dot pattern from the service signal generator.
(2)Use the 2 pieces of main 4-pole magnets of P/C magnets, change the open angle, and align the red and blue vertical
lines on the screen center.
(3)Freeze the open angle of the main 4-pole magnets, turn them simultaneously, and align the horizontal lines.
(4)Take the same steps for items (2) and (3) above and align red/blue with green on the screen center using two 6-pole
magnets.
A
P/C magnet installing position A
•30"=26.5 mm
•32"=30.5 mm or 32.5 mm
•34"=37 mm
•34"=39 mm
Green Belt
2-pole purity magnet
(27": Magnet is fixed with deflection yoke.)
Main 4-pole convergence magnet (30" : 32")
6-pole convergence magnet (34")
Sub-4-pole convergence magnet (32" : 34")
Sub-4-pole convergence magnet (to be installed on deflection yoke for 30", 32”)
6-pole convergence magnet (30" : 32")
Main 4-pole convergence magnet (34")
Fix the deflection yoke at a position 60% forward from a point
between (6) and (7)
Picture tube
Shift deflection yoke
(6)
(8)
(7) Perform marking of each point on
the tape of picture tube
CRT-D board
P/C Mag
100 60 0%

–5 –
GENERAL ADJUSTMENTS
(5)Adjust the sub-4-pole magnets only in case there is any deviation of Xv bow-shaped convergence. (To be usually set at
the initial position)
Align both sides with the sub-4-pole magnets and minimize the deviation of blue and red with the main 4-pole magnets.
blue
blue
red
red
Main 4-pole magnet
red/blue
red/blue
green
green
6-pole magnet
Xv bow-shaped deviation of convergence
blue
red
Sub-4-pole magnet
■CIRCUMFERENCE CONVERGENCE:
*Perform correction in the following manner.
A
D
E
F
A
B
C
B
C
S
N
D
E
F
A
B
C
D
E
F
N
S
VR3
YV YHC
GH
GH
VR2 VR1
blue
green
red
•Adjust coils and minimize deviation
(The 27”unit has coils underneath it)
blue
green
red
(Parts code:23 948 274) TC-S
Blue color or blue mark
*Insert the correction piece between the
picture tube and the deflection yoke.
(Insertion position of correction
piece)
Bonded surface
blue
green
red
(Parts code:23 948 464)
Transparent
Bonded surface
Adjust VR 1 and minimize the deviation of YH. *Only 27", 30" and 32".
Red
green
blue
Red green blue
Red
green
blue
Red
green
blue
Adjust VR 2 (YHC) and minimize the deviation of YH.
Red
green
blue
Red
green
blue
Red
green
blue
Red green
blue
Adjust VR 3 (YV) and minimize the deviation of YV.
Red
blue
green
Red
blue
green
Red
blue
green
Red
blue
green
Red
blue
green
blue
red
green
Red
blue
green
blue
red
green
■ 30", 27", 32"
■ 34"
27" (Part No. 23 947 371)
32", 30" (Part No. 23 947 121)
34" (Part No. 23 993 080)
Perform correction by inserting the
correction piece into the clear-
ance of terminal board coils of
the deflection yoke.
Note:
Perform insertion by turning the
metal side to the terminal board
side of the deflection yoke.

–6 –
GENERAL ADJUSTMENTS
SERVICE MODE
1. ENTERING TO SERVICE MODE
MUTE
S
(Service mode display)
1/2 MUTE
3) While pressing the MUTE button,
press MENU button on TV set.
2) Press MUTE button
again to keep pressing.
1) Press MUTE button twice
on Remote Control.
2. DISPLAYING THE ADJUSTMENT MENU
1) Press MENU button on TV.
Adjustment mode
Press
Press
Service mode
Item
Data
S
3. KEY FUNCTION IN THE SERVICE MODE
The following key entry during display of adjustment menu provides special functions.
A single horizontal line ON/OFF: TV (ANT)/VIDEO button (on TV)
Test signal selection : TV (ANT)/VIDEO button (on Remote)
Selection of the adjustment items : Channel s/t(on TV or Remote)
Change of the data value : Volume s/t(on TV or Remote)
Adjustment menu mode ON/OFF : MENU button (on TV)
Initialization of the memory (QA02, QA04) : RECALL+Channel (s) button on TV
Initialization of the self diagnostic data: RECALL+Channel (t) button on TV
“RCUT”selection : 1 button
“GCUT”selection : 2 button
“BCUT”selection : 3 button
“CNTX”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

–7 –
GENERAL ADJUSTMENTS
4. SELECTING THE 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 12)
5. ADJUSTING THE DATA
1) Pressing of VOLUME sor tbutton will cahnge 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 AND QA04
After replacing QA02 and QA04, the following initialization is required.
1. Enter the service mode, then select any register item.
2. Press and hold the RECALL button on the Remote, then press the CHANNEL sbutton on the TV. The initialization of QA02
and QA04 has been complated.
3. Check the picture carefully. If necessary, adjust any adjustment item above.
Perform “Programming Channel Memory”on the owner's manual.
CAUTION: Never attempt to initialize the data unless QA02, QA04 has been replaced.
7. TEST SIGNAL SELECTION
1) Every pressing of TV/VIDEO button on the Remote Control in the Service mode changes the built-in test patterns
on screen in the following order.
Normal picture
All white
Signals Picture
•All White
2) Press “8”button while any built-in test pattern to on the screen to output the 1 kHz sound. Press the button again to
cut off the sound.
Note: If the video cable is connected to the VIDEO1 INPUT jack, the built-in pattern signals are not displayed.

– 8 –
GENERAL ADJUSTMENTS
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.
SELF CHECK
NO. 23 * * * * * *
POWER : 000
BUS LINE : OK
BUS CONT : OK
BLOCK : MAIN SUB
SET ID : FF
EEP VER : FF
OPT1 : 02 OPT2 : A4
DVI
NO 23009621
ERR CODE : 030000








Part number of microprocessor (QA01)
Operation number of protection circuit (current limiter) . . . . “000”is normal.
BUS line check “OK”................... Normal
“SCL-GND”or “NG”.......... SCL-GND short circuit
“SDA-GND”or “NG”.......... SDA-GND short circuit
“SCL-SDA”or “NG”........... SCL-SDA short circuit
BUS line ACK (acknowledge) check
“OK”..................... Normal
Display of Location Number . . . . NG
(Display example)
“QA02 NG”, “H001 NG”, “Q501 NG”etc.
Note: The indication of failure place is only one place though failure places are plural. When
repair of a failure place finishes, the next failure place is indicated. (The order of priority of
indication is left side.)
Sync. signal check Green display ..... Normal
Cyan display ...... No check
Red display ........ NG
MAIN....... Main sync
SUB ........ Sub sync (when turn on the PIP)
ID code for TV set
Version of "EEP"
Data for "OPT"