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TOSHIBA CORPORATION
1-1, SHIBAURA 1- CHOME, MINATO-KU, TOKYO 105-8001, JAPAN
FILE NO. 020-200220
SERVICE MANUAL
COLOR TELEVISION
N2WS Chassis
34HDX82, 34HD82
PUBLISHED IN JAPAN.
Aug. 2002
So
(TAC0241)
(TAC0240)


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­ 2 ­
GENERAL
ADJUSTMENTS
TABLE OF CONTENTS
CHAPTER 1 GENERAL ADJUSTMENTS
SAFETY INSTRUCTIONS ........................................................................................................................................ 3
SET-UP ADJUSTMENT ............................................................................................................................................ 4
SERVICE MODE ...................................................................................................................................................... 8
ELECTRICAL ADJUSTMENTS .............................................................................................................................. 11
CIRCUIT CHECKS ................................................................................................................................................. 13
CHAPTER 2 SPECIFIC INFORMATIONS
SETTING & ADJUSTING DATA .............................................................................................................................. 14
LOCATION OF CONTROLS ................................................................................................................................... 15
PROGRAMMING CHANNEL MEMORY ................................................................................................................. 17
CHASSIS AND CABINET REPLACEMENT PARTS LIST ......................................................................................18
PC BOARDS BOTTOM VIEW ................................................................................................................................ 35
TERMINAL VIEW OF TRANSISTORS ................................................................................................................... 43
CIRCUIT BLOCK DIAGRAM .................................................................................................................................. 46
SPECIFICATIONS .............................................................................................................................................. END
APPENDIX:
CIRCUIT DIAGRAM


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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 hazard-
ous 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 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 14)
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
0.15
µF
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.


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­ 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 THIS MANUAL.
SET-UP ADJUSTMENT
s 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: 1. The PURITY/CONVERGENCE MAGNET assembly and rubber wedges need mechanical positioning.
Refer to figure 1.
2. 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)
COLOR PURITY ADJUSTMENT
NOTE : Before attempting any purity adjustments, the
receiver should be operated for at least fifteen
minutes.
1. Evenly degauss the entire screen.
2. Set the CONTRAST and BRIGHTNESS Controls to
the maximum.
3. Display built-in green raster using the TEST SIGNAL
SELECTION function.
4. Loosen the clamp screw holding the deflection yoke
(and remove the rubber Wedges).
5. Slide the yoke forward or backward to provide vertical
green belt (zone) in the picture screen.
6. Rotate and spread the tabs of the purity magnet (See
figure 4.) around the neck of the picture tube until the
green belt is in the center of the screen. At the same
time, center the raster vertically by adjusting the mag-
net as shown below.
7. Move the yoke slowly forward or backward until a uni-
form green screen is obtained. Tighten the clamp screw
of the yoke temporarily.
8. Check the purity of the red and blue raster.
9. Put four wedges into the space between the picture
tube and the yoke to hold the yoke in the adjusted
position. (See figure 2.)
Do not tilt the yoke by excessive insertion of the wedge.
10. Remove cover paper of wedge and stick wedges on
the tube to fix the yoke in the adjusted position.
Fix the wedges with glass cloth tapes.
Green Belt
DEFLECTION YOKE
1-5/8"
PURITY/
CONV.
MAGNET
Xv Coil
Adhesive
RUBBER WEDGES
DEFLECTION
YOKE
Figure 2.
Figure 1.


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GENERAL
ADJUSTMENTS
CONVERGENCE ADJUSTMENTS
NOTE: Before attempting any convergence adjustments,
the receiver should be operated for at least fifteen
minutes.
s
CENTER CONVERGENCE ADJUSTMENT
1. Display built-in cross-dot pattern using the TEST SIG-
NAL SELECTION function.
2. Adjust the BRIGHTNESS and CONTRAST Controls
for well defined pattern.
3. Loosen the tightening ring and adjust two tabs of the
4-Pole Magnets to change the angle between them
(See figure 4.) and superimpose red and blue vertical
lines in the center area of the picture screen.
(See figure 3.)
4. Turn the both tabs at the same time keeping the con-
stant angle to superimpose red and blue horizontal
lines at the centre of the screen. (See figure 3.)
5. Adjust two tabs of 6-Pole Magnets to superimpose red/
blue line with 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 interact and make dot movement com-
plex.
7. After completing the "CENTER CONVERGENCE AD-
JUSTMENT" tighten the tightening ring to fix the mag-
nets.
Figure 3.
s
Xv COIL ADJUSTMENT
Adjust the Xv coil (on the deflection yoke) to correct
misconvergence at both sides on screen.
Use a hexagonal tip stick (plastic) to adjust the core of
coil.
BLU
BLU RED
RED
6-POLE MAGNETS
MOVEMENT
4-POLE MAGNETS
MOVEMENT
RED/BLUE
RED/BLUE GRN
GRN
Center Convergence by Convergence Magnets
R
B
B
R
B
R
R
B
Clockwise Adjustment Counterclockwise Adjustment
Xv Cross Pattern View
s
SCREEN-CORNER CONVERGENCE
When the misconvergence is still evident on corners even
though the above adjustment is done, use the ferrite sheet
(Part No. 23993622) to correct misconvergence.
1. Put ferrite sheets into the space under the yoke.
Decide such position that misconvergence becomes
minimum, watching picture screen. (See figure below.)
2. Remove cover paper of ferrite sheet to stick it in the
place on the tube. Put adhesive tapes on ferrite sheets
to fix.
Figure 4.
Ferrite
Sheets
Ferrite
Sheets
For correcting misconvergence
on the position A
A
4-POLE
MAGNETS
6-POLE
MAGNETS
PURITY
MAGNETS
PURITY/CONVERGENCE
MAGNETS
ADJUST THE ANGLE
(VERTICAL LINES)
FIXED
ROTATE TWO TABS
AT THE SAME TIME
(HORIZONTAL LINES)
ADJUSTMENT OF MAGNETS
Clockwise Adjustment
Counterclockwise Adjustment
XV Cross Pattern View