TOSHIBA 34HD82, 34HDX82 Service Manual

FILE NO. 020-200220
SERVICE MANUAL
COLOR TELEVISION
N2WS Chassis
34HDX82, 34HD82
PUBLISHED IN JAPAN. Aug. 2002 So
CHAPTER 1 GENERAL ADJUSTMENTS
SAFETY INSTRUCTIONS ........................................................................................................................................ 3
SET-UP ADJUSTMENT ............................................................................................................................................ 4
SERVICE MODE ...................................................................................................................................................... 8
ELECTRICAL ADJUSTMENTS .............................................................................................................................. 11
CIRCUIT CHECKS ................................................................................................................................................. 13
CHAPTER 2 SPECIFIC INFORMATIONS
GENERAL ADJUSTMENTS
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

TABLE OF CONTENTS

APPENDIX:
CIRCUIT DIAGRAM
– 2 –

CHAPTER 1 GENERAL ADJUSTMENTS

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

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 120V AC power source. The high voltage must not, under any cir­cumstances, 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 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
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, follow­ing 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 pro­tection, 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 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
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; 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:
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 combi­nation of 1500 ohm resistor and 0.15 µF capacitor. Re­verse 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 consti­tutes a potential shock hazard and must be corrected im­mediately.
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.
PRODUCT SAFETY NOTICE
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.
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.
GENERAL ADJUSTMENTS
*
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)

SET-UP ADJUSTMENT

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 mag­net as shown below.
Figure 1.
Xv Coil
DEFLECTION YOKE
1-5/8
PURITY/ CONV. MAGNET
RUBBER WEDGES
Adhesive
Green Belt
7. Move the yoke slowly 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.
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.
DEFLECTION YOKE
Figure 2.
4
CONVERGENCE ADJUSTMENTS
NOTE: Before attempting any convergence adjustments,
the receiver should be operated for at least fifteen minutes.
CENTER CONVERGENCE ADJUSTMENT
1. Display built-in cross-dot pattern using the TEST SIG­NAL 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 con­stant 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 6­Pole magnets interact and make dot movement com­plex.
7. After completing the “CENTER CONVERGENCE AD- JUSTMENT tighten the tightening ring to fix the mag­nets.
6-POLE MAGNETS
PURITY MAGNETS
ADJUST THE ANGLE (VERTICAL LINES)
4-POLE MAGNETS
PURITY/CONVERGENCE MAGNETS
FIXED
ROTATE TWO TABS AT THE SAME TIME (HORIZONTAL LINES)
GENERAL ADJUSTMENTS
BLU RED
BLU
RED
4-POLE MAGNETS MOVEMENT
Center Convergence by Convergence Magnets
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.
Clockwise Adjustment Counterclockwise Adjustment
Clockwise Adjustment
R
B
RED/BLUE
Figure 3.
Counterclockwise Adjustment
RED/BLUE GRN
GRN
6-POLE MAGNETS MOVEMENT
B
R
ADJUSTMENT OF MAGNETS
Figure 4.
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.
Ferrite
Sheets
Sheets
Ferrite
B
R
Xv Cross Pattern View
XV Cross Pattern View
R
B
– 5 –
A
For correcting misconvergence on the position A
WARNING: BEFORE SERVICING THIS CHASSIS, READ THE X-RAY RADIATION PRECAUTION”, SAFETY PRECAU-
TION AND PRODUCT SAFETY NOTICE ON PAGE 3 OF SERVICE MANUAL.
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
GENERAL ADJUSTMENTS
(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.
(SET-UP ADJUSTMENT FOR FLAT TUBE)
Figure 1.
2-pole purity magnet
(27": Magnet is fixed with deflection yoke.)
Green Belt
Sub-4-pole convergence magnet (32" : 34") Sub-4-pole convergence magnet (to be installed on deflection yoke for 30", 32”)
Main 4-pole convergence magnet (30" : 32") 6-pole convergence magnet (34") 6-pole convergence magnet (30" : 32") Main 4-pole convergence magnet (34")
P/C magnet installing position A
• 30"=26.5 mm
A
• 32"=30.5 mm or 32.5 mm
• 34"=37 mm
• 34"=39 mm
(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
Shift deflection yoke
(7) Perform marking of each point
(6)
(8)
on the tape of picture tube
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
Picture tube
CRT-D board
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
100 60 0%
Fix the deflection yoke at a position 60% forward from a point between (6) and (7)
P/C Mag
* 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.
– 6 –
(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
6-pole magnet
CIRCUMFERENCE CONVERGENCE:
Perform correction in the following manner.
*
blue
green red
A
B
C
(Parts code:23 948 274) TC-S
blue
green
red
S N
Blue color or blue mark
D
E
F
*Insert the correction piece between the picture tube and the deflection yoke.
Bonded surface
(Insertion position of correction piece)
D
E
F
A
B
C
Adjust VR 1 and minimize the deviation of YH. *Only 27", 30" and 32".
Red
green
blue
blue
green
Red
Xv bow-shaped deviation of convergence
blue
green
red
Sub-4-pole magnet
Adjust coils and minimize deviation (The 27 unit has coils underneath it)
A
B
C
30", 27", 32"
blue
green
red
(Parts code:23 948 464)
N S
Transparent
GENERAL ADJUSTMENTS
D
E
F
Bonded surface
Red
green
blue
blue
green
Red
Adjust VR 2 (YHC) and minimize the deviation of YH.
Red
blue
green
green
blue
Red
blue
Red
green
green
Red
blue
Adjust VR 3 (YV) and minimize the deviation of YV.
Red
green
blue
blue
green
Red
GH
Red
blue
green
green
blue
red
green
blue
red
green
green
Red
7
blue
Red
Red
blue
blue
green
VR3
VR2 VR1
34"
YV YHC
27" (Part No. 23 947 371) 32", 30" (Part No. 23 947 121) 34" (Part No. 23 993 080)
GH
Perform correction by inserting the
correction piece into the clear­ance 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.
1. ENTERING TO SERVICE MODE
1) Press MUTE button twice on Remote Control.

SERVICE MODE

2) Press MUTE button again to keep pressing.
3) While pressing the MUTE button, press MENU button on TV set.
S
1/2 MUTE
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.
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 buttonGCUT selection : 2 buttonBCUT selection : 3 buttonCNTX selection : 4 buttonCOLC selection : 5 buttonTNTC selection : 6 button
Test audio signal ON/OFF (1kHz) : 8 button Self diagnostic display ON/OFF : 9 button
MUTE
(Service mode display)
Adjustment mode
S
Press
Press
Item
Data
– 8 –
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 14)
5. ADJUSTING THE DATA
1) Pressing of VOLUME s or t button 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 s button 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.
GENERAL ADJUSTMENTS
Signals Picture
Normal 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.
All White
9
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 ICs are executed properly.
2) During diagnosis, the following displays are shown.
SELF CHECK
    
NO. 23 * * * * * * POWER : 000 BUS LINE : OK BUS CONT : OK BLOCK : UV V1 V2 or QV01 QV01S SYNC
GENERAL ADJUSTMENTS
Part number of microprocessor (QA01)
Operation number of protection circuit (current limiter) . . . . 000 is normal.
BUS line check OK................... Normal
BUS line ACK (acknowledge) check
Sync. signal check Green display ..... 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
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.)
Cyan display ...... No check
Red display ........ NG
UV ........... TV mode
V1 ........... VIDEO 1 mode
V2 ........... VIDEO 2 mode
The items marked with are not usable to display in the SELF DIAGNOSTIC FUNCTION for some model.
*
– 10 –

ELECTRICAL ADJUSTMENTS

ITEM ADJUSTMENT PROCEDURE
FOCUS VR ADJ
SUB-BRIGHTNESS (BRTC)
SUB-COLOR (SCOL) SUB-TINT (TNTC)
1. Enter the service mode, then select any register item.
2. Press the TV/VIDEO button on the Remote until the black cross-bar pattern ap­pears on the screen.
3. Adjust the FOCUS control (on T461) for well defined scanning lines on the picture screen.
1. Constrict the picture height until the verti­cal retrace line appears adjusting the item HIT (HEIGHT).
2. Adjust the CONTRAST control to the mini­mum.
3. Call up the adjustment mode display, then select the item BRTC.
4. Press the VOLUME s or t button so the belt of vertical retrace line just disappear.
5. Adjust the CONTRAST control for the de­sired contrast.
6. Perform the HEIGHT adjustment.
Vertical retrace line
1. Receive color-bar signal from color-bar generator.
2. Press the RESET button.
3. Connect oscilloscope to TP501 on SIG­NAL board.
4. Adjust the CONTRAST control to the minimum.
Magenta
0
Blue
2
3 (1.6V
5. Call up the adjustment mode display, then select the item TNTC.
6. Adjust the SUB-TINT by pressing the VOLUME s or t button to obtain a blue bar to magenta bar ratio of 3:2 as shown.
7. Press the RESET button.
8. Select the item SCOL.
9. Adjust the SUB-COLOR by pressing the VOLUME s or t button to achieve
1.6V0-p of a blue bar on scope.
10. Check the picture with off-air signal.
0-P
GENERAL ADJUSTMENTS
)
WIDTH (WID)
1. Call up the adjustment mode display, then select the item WID.
2. Press the VOLUME s or t button to get the picture so the left and right edges of
raster begins to lack.
3. Press the VOLUME s or t button to advance the data by 7 steps.
Note : Check the horizontal picture position is correct.
– 11 –
ITEM ADJUSTMENT PROCEDURE
E-W PARABOLA (DPC) (PARA)
GENERAL ADJUSTMENTS
HORIZONTAL POSITION (HPOS) VERTICAL POSITION (VPOS)
HEIGHT (HIT)
1. Call up the adjustment mode display, then select the item PARA.
2. Press the TV/VIDEO button on Remote until the cross-hatch pattern appears on
the screen.
3. Press the VOLUME s or t button to make vertical lines straight as shown below.
1. Call up the adjustment mode display, then select the item HPOS or VPOS.
2. Press the TV/VIDEO button on Remote until the
white cross-bar or black cross-bar pattern appears on the screen.
3. Adjust the HORIZONTAL and VERTICAL position
alternately by pressing the VOLUME s or t but­ton for proper picture position.
4. Check the picture with off-air signal.
1. Call up the adjustment mode display, then select the item HIT.
2. Press the VOLUME s or t button to get the picture so the top of raster begins to
lack.
3. Press the VOLUME s button to advance the data by 9 steps.
Note : Check the vertical picture position is correct.
WHITE BALANCE (RCUT) (GCUT) (BCUT) (GDRV) (BDRV)
1. Adjust the CONTRAST control to the center, and BRIGHTNESS control to the maximum.
2. Call up the adjustment mode display, and press the TV/VIDEO button on Remote until the white and black pattern appears on the screen.
3. Adjust the following items with the CHANNEL s/t and VOLUME s/t buttons.
RCUT
Item :
GCUT
Item :
BCUT
Item :
4. Press the TV/VIDEO button on TV to display a single horizontal line on the screen.
5. Turn the SCREEN control (FBT) fully counterclockwise and gradually rotate clock­wise until the first horizontal line appears slightly on the screen.
6. Press the TV/VIDEO button to display the normal picture.
7. Adjust the remaining two “?CUT” items (CHANNEL s/t TV/VIDEO VOL- UME s/t in order) to obtain the slightly lighted horizontal line in the same levels of three (red, green, blue) colors. The line should be white if the adjustments are proper.
Data : 40H Data : 40H Data : 40H
Bright area Adjust "GDRV" or "BDRV" to be white.
Dark area Fine adjust "RCUT", "GCUT" or "BCUT" to be black.
Item :
GDRV Data : 40H
Item :
BDRV Data : 40H
– 12 –

CIRCUIT CHECKS

HIGH VOLTAGE CHECK CAUTION: There is no HIGH VOLTAGE ADJUSTMENT on
this chassis. Checking should be done following the steps below.
1. Connect an accurate high voltage meter to the second an­ode of the picture tube.
2. Turn on the receiver. Set the BRIGHTNESS and CON­TRAST controls to minimum (zero beam current).
3. High voltage must be measured below (B) kV.
Refer to table-1 for high voltage (B). (See SETTING & ADJUSTING DATA on page 14)
4. Vary the BRIGHTNESS control to both extremes to be sure the high voltage does not exceed the limit under any con­ditions.
FS CIRCUIT CHECK
The Fail Safe (FS) circuit check is indispensable for the final check in servicing. Checking should be done following the steps below.
1. Turn the receiver on and press the RESET button.
2. Temporarily short TP-(R) and TP-(X) with a jumper wire. Raster and sound will disappear.
3. The receiver must remain in this state even after removing the jumper wire. This is the evidence that the FS circuit is functioning properly.
4. To obtain a picture again, temporarily turn the receiver off and allow the FS circuit more than 5 seconds to reset. Then turn the power switch on to produce a normal pic­ture.
Troubleshooting Guide for Fail Safe Circuit
Check that the set returns to normal operation when pin 12 of Z801(or emitter of Q472) is grounded with jumper wire.
YES NO
Check the voltage across Capacitor C471 is approximately
Refer to table –4 for FBT detection voltage
YES
Defective Fail Safe Circuit
(C)
volts.
(C)
(See SETTING & ADJUSTING DATA on page14)
.
NO
Faulty power circuit or hori­zontal circuit.
GENERAL ADJUSTMENTS
13

CHAPTER 2 SPECIFIC INFORMATIONS

SAFETY INSTRUCTIONS
SERVICE MODE
GENERAL ADJUSTMENTS
ADJUSTING ITEMS AND DATAS IN THE SERVICE MODE:

SETTING & ADJUSTING DATA

34" HIGH VOLTAGE AT ZERO BEAM: (A) 32.2 kV MAX HIGH VOLTAGE:
Table-1
(B) 33.6 kV
Item Name of adjustment
RCUT GCUT BCUT GDRV BDRV BRTC TNTC
SPECIFIC INFORMATIONS
SCOL SCNT HIT LIN WID PARA
OPTION: (PROGRESSIVE 4:3 DV)
MODELS D7 D6 D5 D4 D3 D2 D1 D0 HEX D7 D6 D5 D4 D3 D2 D1 D0 HEX 34HF81 0 10110104AH0000010125H
R CUTOFF G CUTOFF B CUTOFF G DRIVE B DRIVE BRIGHT CENT TINT CENT SUB-COLOR SUB-CONTRAST HEIGHT V-LINEARITY PICTURE WIDTH E-W PARABOLA
Preset
40H 40H 40H 40H 40H 80H 46H 0EH 10H 38H 12H 36H 16H
OPT1 (2CAH) OPT2(2CBH)
NORMAL
& FULL
Table-2
Item Name of adjustment Preset
CNR TRAP HPS CPAR CSAW TCNR BCNR VPSI PHUE PCNT PCOL
E-W CORNER TRAPEZIUM H-POSITION CENTER PARA CENTER/SAW EW TOP CORNER EW BOTTOM COR V-SHIFT PIP TINT PIP CONTRAST PIP COLOR
14H 39H 39H 08H 07H 14H 16H 82H 40H 0FH 19H
NORMAL
& FULL
CIRCUIT CHECKS
Table-3
FBT DETECTION VOLTAGE (C) 18.9 V
Table-4
14
Loading...
+ 30 hidden pages