Sharp 27SC26B User manual

SHARP CORPORATION This document has been published to be used for after
sales service only.
The contents are subject to change without notice.
In the interests of user-safety (Required by safety regulations in some countries ) the set should be restored to its
original condition and only parts identical to those specified should be used.
Page
»ELECTRICAL SPECIFICATIONS .........................................................................................................1
»IMPORTANT SERVICE SAFETY PRECAUTION .................................................................................2
»LOCATION OF USER'S CONTROL.....................................................................................................4
»INSTALLATION AND SERVICE INSTRUCTIONS................................................................................5
»SERVICE ADJUSTMENT .....................................................................................................................9
»CHASSIS LAYOUT .............................................................................................................................12
»BLOCK DIAGRAM ..............................................................................................................................13
»DESCRIPTION OF SCHEMATIC DIAGRAMS& WAVEFORMS........................................................14
»SCHEMATIC DIAGRAMS...................................................................................................................15
»PRINTED WIRING BOARD ASSEMBLIES ........................................................................................22
»PARTS LIST........................................................................................................................................27
»PACKING OF THE SET......................................................................................................................36
CONTENTS
SPEAKER
SIZE ..........................................................9 x 5 cm oval (2 pcs.)
VOICE COIL IMPEDANCE ............................ 16 ohm at 400 Hz
ANTENNA INPUT IMPEDANCE
VHF/UHF.....................................................75 ohm Unbalanced
TUNING RANGES
VHF-Channels...............................................................2 thru 13
UHF-Channels............................................................14 thru 69
CATV Channels...........................................................1 thru 125
POWER INPUT..................................................... 120VAC, 60 Hz
POWER RATING...................................................................130W
PICTURE SIZE .......................................... 2,187 cm2 (339sq inch)
CONVERGENCE ............................................................. Magnetic
SWEEP DEFLECTION .................................................... Magnetic
FOCUS ............................................... Hi-Bi-Potential Electrostatic
INTERMEDIATE FREQUENCIES
Picture IF Carrier Frequency ...... 45.75 MHz (Analog Terrestrial)
Sound IF Carrier Frequency....... 41.25 MHz (Analog Terrestrial)
Color Sub-Carrier Frequency ..... 42.17 MHz (Analog Terrestrial)
(Nominal)
AUDIO POWER
OUTPUTRATING..............3.0W + 3.0W (at 10% distortion and
Dual CH Operate)
Specifications are subject to change without
prior notice.
ELECTRICAL SPECIFICATIONS
MODEL
SERVICE MANUAL
27SC26B
COLOR TELEVISION
Digital Terrestrial Broadcast (VHF/UHF) .......................2 thru 69
Chassis No. GB-3D(1W)
IF Center Frequency ........................ 44 MHz (Digital Terrestrial)
(EIA, Channel Plan U.S.A.)
27SC26B

IMPORTANT SERVICE SAFETY PRECAUTION
ËService work should be performed only by qualified service technicians who are
thoroughly familiar with all safety checks and the servicing guidelines which follow:
CAUTION: FOR CONTINUED
PROTECTION AGAINST A
RISK OF FIRE, REPLACE
ONLYWITH SAME TYPE 4A-
125V FUSE.
X-RADIATION AND HIGH VOLTAGE LIMITS
1. Be sure all service personnel are aware of the
procedures and instructions covering X-radiation. The
only potential source of X-ray in current solid state
TV receivers is the picture tube. However, the picture
tube does not emit measurable X-Ray radiation, if
the high voltage is as specified in the "High Voltage
Check" instructions.
It is only when high voltage is excessive that X-
radiation is capable of penetrating the shell of the
picture tube including the lead in the glass material.
The important precaution is to keep the high voltage
below the maximum level specified.
2. It is essential that servicemen have available at all
times an accurate high voltage meter.
The calibration of this meter should be checked
periodically.
3. High voltage should always be kept at the rated value
−no higher. Operation at higher voltages may cause
a failure of the picture tube or high voltage circuitry
and;also, under certain conditions, may produce
radiation in exceeding of desirable levels.
4. When the high voltage regulator is operating properly
there is no possibility of an X-radiation problem. Every
time a color chassis is serviced, the brightness should
be tested while monitoring the high voltage with a
meter to be certain that the high voltage does not
exceed the specified value and that it is regulating
correctly.
5. Do not use a picture tube other than that specified or
make unrecommended circuit modifications to the
high voltage circuitry.
6. When trouble shooting and taking test measurements
on a receiver with excessive high voltage, avoid being
unnecessarily close to the receiver.
Do not operate the receiver longer than is necessary
to locate the cause of excessive voltage.
WARNING
1. For continued safety, no modification of any circuit
should be attempted.
2. Disconnect AC power before servicing.
3. Semiconductor heat sinks are potential shock hazards
when the chassis is operating.
4. The chassis in this receiver has two ground systems
which are separated by insulating material. The non-
isolated (hot) ground system is for the B+ voltage
regulator circuit. The isolated ground system is for
the low B+ DC voltages and the secondary circuit of
the high voltage transformer.
To prevent electrical shock use an isolation
transformer between the line cord and power
receptacle, when servicing this chassis.
SERVICING OF HIGH VOLTAGE SYSTEM
AND PICTURE TUBE
When servicing the high voltage system,
remove the static charge by connecting a
10k ohm resistor in series with an insulated
wire (such as a test probe) between the pic-
ture tube ground and the anode lead. (AC
line cord should be disconnected from AC
outlet.)
1. Picture tube in this receiver employs integral
implosion protection.
2. Replace with tube of the same type number for
continued safety.
3. Do not lift picture tube by the neck.
4. Handle the picture tube only when wearing
shatterproof goggles and after discharging the high
voltage anode complT
4A 125V
27SC26B
2

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SAFETY NOTICE
Many electrical and mechanical parts in television
receivers have special safety-related characteristics.
These characteristics are often not evident from visual
inspection, nor can protection afforded by them be
necessarily increased by using replacement components
rated for higher voltage, wattage, etc.
Replacement parts which have these special safety
characteristics are identified in this manual; electrical
components having such features are identified by "å"
and shaded areas in the Replacement Parts Lists and
Schematic Diagrams.
IMPORTANT SERVICE SAFETY PRECAUTION
(Continued)
1. Inspect all lead dress to make certain that leads are
not pinched or that hardware is not lodged between
the chassis and other metal parts in the receiver.
2. Inspect all protective devices such as non-metallic
control knobs, insulating materials, cabinet backs,
adjustment and compartment covers or shields,
isolation resistor-capacity networks, mechanical
insulators, etc.
3. To be sure that no shock hazard exists, check for
leakage current in the following manner.
•Plug the AC cord directly into a 120 volt AC outlet,
(Do not use an isolation transformer for this test).
•Using two clip leads, connect a 1.5k ohm, 10 watt
resistor paralleled by a 0.15µF capacitor in series with
all exposed metal cabinet parts and a known earth
ground, such as electrical conduit or electrical ground
connected to earth ground.
•Use an AC voltmeter having with 5000 ohm per volt,
or higher, sensitivity to measure the AC voltage drop
across the resistor.
BEFORE RETURNING THE RECEIVER
(Fire & Shock Hazard)
Before returning the receiver to the user, perform
the following safety checks.
•Connect the resistor connection to all exposed metal
parts having a return to the chassis (antenna, metal
cabinet, screw heads, knobs and control shafts,
escutcheon, etc.) and measure the AC voltage drop
across the resistor.
AII checks must be repeated with the AC line cord
plug connection reversed. (If necessary, a non-
polarized adapter plug must be used only for the
purpose of completing these check.)
Any current measured must not exceed 0.5 milliamp.
Any measurements not within the limits outlined
above indicate of a potential shock hazard and
corrective action must be taken before returning the
instrument to the customer.
For continued protection, replacement parts must be
identical to those used in the original circuit. The use of
substitute replacement parts which do not have the same
safety characteristics as the factory recommended
replacement parts shown in this service manual, may
create shock, fire, X-radiation or other hazards.
1.5k ohm
10W
0.15µF
TEST PROBE
TO EXPOSED
METAL PARTS CONNECT TO
KNOWN EARTH
GROUND
27SC26B
3

TV
ENTER
VOLUME UP/DOWN
(+) Increases sound.
(–) Decreases sound.
CHANNEL UP/DOWN
()Selects next higher channel.
()Selects next lower channel.
VIDEO/AUDIO IN 2
TERMINALS
REMOTE CONTROL
SENSOR
POWER
Press On.
Press again Off.
MENU
Press Accesses MAIN MENU.
Press again Exits MAIN MENU.
Front Panel
LOCATION OF USER'S CONTROL
Basic Remote Control Functions
POWER
Press On.
Press again Off.
REMOTE KEYPAD
Accesses any channel from keypad.
Returns to previous channel.
FLASHBACK
VOLUME UP/DOWN
(+) Increases sound.
(–) Decreases sound.
• Changes or selects the TV
adjustments on On-Screen Display.
MUTE
Press Mutes sound.
Press again Restores sound.
INPUT
Press Switches to external video
INPUT 1 mode.
Press twice Switches to external video
INPUT 2 mode.
Press 3 times Switches back to
the original TV mode.
ENTER
Used in some instances where a Cable
Converter Box requires an “enter”
Command after selecting channels,
when using the REMOTE KEYPAD
Button.
CHANNEL UP/DOWN
()Selects next higher channel.
()Selects next lower channel.
• Moves the" "mark on the MENU
screens.
Infrared Transmitter Window
DISPLAY
Press Displays receiving channel
for 4 seconds.
Press again Removes display.
• Temporarily displays receiving
channel when in Closed Caption
mode.
MENU
Press Accesses MAIN MENU.
Press again Exits MAIN MENU.
Note:
•The above shaded buttons on the Remote Control glow in the dark. To use the glow-in-the-dark
display on the remote control, place it under a fluorescent light or other lighting.
•The phosphorescent material contains no radioactive or toxic material, so it is safe to use.
• The degree of illumination will vary depending on the strength of lighting used.
• The degree of illumination will decrease with time and depending on the temperature.
•The time needed to charge the phosphorescent display will vary depending on the surrounding lighting.
• Sunlight and fluorescent lighting are the most effective when charging the display.
•The TV set and remote control illustrations and the on-screen displays in this manual may differ from
their actual appearance.
27SC26B
4

CIRCUIT PROTECTION
The receiver is protected by a 4.0A fuse (F701),
mounted on PWB-A, wired into one side of the AC
line input.
X-RADIATION PROTECTOR CIRCUIT TEST
After service has been performed on the horizontal
deflection system, high voltage system, B+ system,
test the X-Radiation protection circuit to ascertain
proper operation as follows:
1. Apply 120V AC using a variac transformer for accurate
input voltage.
2. Allow for warm up and adjust all customer controls
for normal picture and sound.
3. Receive a good local channel.
4. Connect a digital voltmeter to TP653 (P651 Pin3) and
make sure that the voltmeter reads 13.85 ±0.6V DC.
5. Apply external 17.3V DC at TP653 by using an
external DC supply, TV must be shut off.
6. To reset the protector, unplug the AC cord (about
1min.) and plug the AC cord power on. Now make
sure that normal picture appears on the screen.
7. If the operation of the horizontal oscillator does not
stop in step 5, the circuit must be repaired before the
set is returned to the customer.
HIGH VOLTAGE CHECK
High voltage is not adjustable but must be checked
to verify that the receiver is operating within safe
and efficient design limitations as specified checks
should be as follows:
1. Connect an accurate high voltage meter between
ground and anode of picture tube.
2. Operate receiver for at least 15 minutes at 120V AC
line voltage, with a strong air signal or a properly tuned
in test signal.
3. Enter the service mode and select the service
adjustment "V11" and Bus data "01" (Y-mute on, CRT
Cut Off).
4. The voltage should be below 30.5kV (at zero beam).
If a correct reading cannot be obtained, check circuitry
for malfunctioning components. After the voltage test,
make Y-mute off to the normal mode.
INSTALLATION AND SERVICE INSTRUCTIONS
Note: (1) When performing any adjustments to resistor controls and transformers use non-metallic
screwdrivers or TV alignment tools.
(2) Before performing adjustments, the TV set must be on at least 15 minutes.
27SC26B
5

For adjustments of this model, the bus data is converted to various analog signals by the D/A converter
circuit.
Note: There are still a few analog adjustments in this series such as focus and master screen voltage.
Follow the steps below whenever the service adjustment is required. See "Table-B" to determine, if serv-
ice adjustments are required.
1. Service mode
Before putting unit into the service mode, check that
customer adjustments are in the normal mode. Use
the reset function in the video adjustment menu to
ensure customer controls are in their proper (reset)
position.
2. Service number selection
Once in the service mode, press the Ch-up or Ch-
down button on the remote controller or at the set.
The service adjustment number will vary in
increments of one, from "V01" to "M05". Select the
item you wish to adjust.
3. Data number selection
Press the Vol-up or Vol-down button to adjust the data
number.
To enter the service mode and exit serv-
ice mode.
To enter the service mode manually just press and hold
the Vol-down and Ch-up buttons at the same time, plug
the AC cord into a wall socket.
Now the TV set is switched on and enters the service
mode.
To exit the service mode, turn the television off by
pressing the power button.
4. Donau and Main Micon version Check
1. After television power on, press test key “ox31”
and the following screen will display.
Figure A.
V05 2
CHANNEL
SERVICE ADJUSTMENT NUMBER
DATA NUMBER
3F(063)
VERSION NUMBER
ANALOG : 1.10 - 34
DIGITAL : 1.21
DIGITAL OS : 0400140P-105
* ANALOG – RH-IXB644WJQZQ
IC software version
* DIGITAL – Donau IC software inside
Tuner RTUDAA001WJQZ
2. The version display screen will disappear after 30
second or pressing any key (except test key) will
cancel the version display.
27SC26B
6

V01 PICTURE 0-15 (00h-0Fh) 08 (08h)
V02 TINT 0-127 (00h-7Fh) 66 (42h)
V03 COLOR 0-127 (00h-7Fh) 56 (38h)
V05 BRIGHT 0-127 (00h-7Fh) 64 (40h)
V06 R CUT-OFF 64-255 (40h-FFh) 64 (40h)
V07 G CUT-OFF 64-255 (40h-FFh) 64 (40h)
V08 B CUT-OFF 64-255 (40h-FFh) 64 (40h)
V09 G/R DRIVE 0-127 (00h-7Fh) 64 (40h)
V10 B DRIVE 0-127 (00h-7Fh) 64 (40h)
V11Y-MUTE/V-STOP 0-2 00 (00h) Y-Mute / Horizontal “—” 00
V12 SHARP 0-63 (00h-3Fh) 50 (32h) 32
V13 DC RESTORATION 0-3 (00h-03h) 02 (02h) 02
V14 BLACK STRETCH 0-3 (00h-03h) 02 (02h) 02
V15 ABL STARTPOINT 0-3 (00h-03h) 03 (03h) 03
V16 ABL GAIN 0-3 (00h-03h) 02 (02h) 02
V17 γPOINT 0-3 (00h-03h) 00 (00h) 00
V19 ENERGY SAVE 0-63 (00h-3Fh) 63 (3Fh) Offset 3F
V24 LOW-G 0-255 (00h-FFh) 12 (0Ch) Color Temp. 0C
V25 LOW-B 0-255 (00h-FFh) 241 (F1h) Color Temp. F1
V26 ML-G 0-255 (00h-FFh) 00 (00h) Color Temp. 00
V27 ML-B 0-255 (00h-FFh) 247 (F7h) Color Temp. F7
V28 HIGH-G 0-255 (00h-FFh) 02 (02h) Color Temp. 02
V29 HIGH-B 0-255 (00h-FFh) 08 (08h) Color Temp. 08
V30 WPL 0-1 01 (01h) 01
V31 RGB CONTRAST 0-63 (00h-3Fh) 59 (3Bh) 3B
V34 VSM GAIN 0-3 (00h-03h) 01 (01h) 01
V36 BPF/TOF-INPUT 0-1 00 (00h) External Input 00
V37 CORING 0-1 00 (00h) 00
V38 VSM PHASE 0-1 00 (00h) 00
V39 COLOR γ0-1 00 (00h) 00
V40 SHARP-INPUT 0-63 (00h-3Fh) 44 (2Ch) External Input 2C
V41 TINT-INPUT 0-127 (00h-7Fh) 62 (3Eh) External Input 3E
V42 PICTURE-COMPONENT 0-15 (00h-0Fh) 6 (06h) Component Input
V43 TINT-COMPONENT 0-127 (00h-7Fh) 62 (3Eh) Component Input 3E
V44 COLOR-COMPONENT 0-127 (00h-7Fh) 72 (48h) Component Input 48
V45 BRIGHT-COMPONENT 0-127 (00h-7Fh) 84 (54h) Component Input
V46 R CUT OFF-COMPONENT 64-255 (40h-FFh) 64 (40h) Component Input
V47 G CUT OFF-COMPONENT 64-255 (40h-FFh) 64 (40h) Component Input
V48 B CUT OFF-COMPONENT 64-255 (40h-FFh) 64 (40h) Component Input
V49 G/R DRIVE-COMPONENT 0-127 (00h-7Fh) 64 (40h) Component Input
V50 B DRIVE-COMPONENT 0-127 (00h-7Fh) 64 (40h) Component Input
V51 SHARP-COMPONENT 0-63 (00h-3Fh) 44 (2Ch) Component Input 2C
V52 TINT-S 0-127 (00h-7Fh) 62 (3Eh) S-Terminal Input 3E
V53 C-TRAP 0-1 (00h-01h) 00 (00h) 00
V59 AUTO FRESH 0-1 (00h-01h) 00 (00h) 00
V60 SHARP P F 0-1 (00h-01h) 01 (01h) 01
V61 CD MATRIX 0-3 (00h-03h) 02 (02h) 02
V62 B-Y ATT 0-1 (00h-01h) 00 (00h) 00
V63 R-Y ATT 0-1 (00h-01h) 00 (00h) 00
V64 CD MATRIX-COMPONENT 0-3 (00h-03h) 00 (00h) Component Input 00
V65 B-Y ATT-COMPONENT 0-1 (00h-01h) 00 (00h) Component Input 00
V66 R-Y ATT-COMPONENT 0-1 (00h-01h) 00 (00h) Component Input 00
V67 BUZZ 0-1 (00h-01h) 01 (01h) 01
V68 RGB ABCL 0-1 (00h-01h) 01 (01h) 01
V69 PICTURE-VCOMP 0-100 (00h-64h) 47 (2Fh) 16:9 Format (Offset) 2F
V70 COLOR-VCOMP 0-100 (00h-64h) 50 (32h) 16:9 Format (Offset) 32
V71 BRIGHT-VCOMP 0-100 (00h-64h) 51 (33h) 16:9 Format (Offset) 33
V72 PICTURE-DTV 0-15 (00h-0Fh) 06 (06h) Digital CH Copy of V01+01h
V73 TINT-DTV 0-127 (00h-7Fh) 62 (3Eh) Digital CH 47
V74 COLOR-DTV 0-127 (00h-7Fh) 72 (48h) Digital CH 60
V75 BRIGHT-DTV 0-127 (00h-7Fh) 84 (54h) Digital CH Copy of V05-01h
V76 R CUT OFF-DTV 64-255 (40h-FFh) 64 (40h) Digital CH Copy of V06
V77 G CUT OFF-DTV 64-255 (40h-FFh) 64 (40h) Digital CH Copy of V07
V78 B CUT OFF-DTV 64-255 (40h-FFh) 64 (40h) Digital CH Copy of V08
V79 G/R DRIVE-DTV 0-127 (00h-7Fh) 64 (40h) Digital CH Copy of V09
V80 B DRIVE-DTV 0-127 (00h-7Fh) 64 (40h) Digital CH Copy of V10
V81 SHARP-DTV 0-63 (00h-3Fh) 44 (2Ch) Digital CH 52
V82 CD MATRIX-DTV 0-3 (00h-03h) 00 (00h) Digital CH 00
V83 B-Y ATT-DTV 0-1 (00h-01h) 00 (00h) Digital CH 00
V84 R-Y ATT-DTV 0-1 (00h-01h) 00 (00h) Digital CH 00
R01 RF-AGC 0-63 (00h-3Fh) 36 (24h)
R03 RF-AGC REF 0-255 (00h-FFh) 170 (AAh) Standard value for the self-adjust. AA
A. VCJ IC ADJUSTMENT
SERVICE
NUMBER
DATA
ADJUSTMENT ITEM
INITIAL VALUE
FIXED VALUE
(HEX)
RANGE
NOTES
27SC26B
7

SERVICE
NUMBER
DATA
ADJUSTMENT ITEM
INITIAL VALUE
NOTES FIXED VALUE
(HEX)
RANGE
EX1 FAO VOLUME 0-50 (00h-32h) 36 (24h) 24
EX2 CC-POSITION 0-127 (00h-7Fh) 27 (1Bh) 1C
EX3 INT 0-255 (00h-FFh) 122 (7Ah) Interrupt period adjustment 7A
EX4 A-ATT 0-127 (00h-7Fh) 90 (5Ah) 5A
EX5 TUNER data 0-3 (00h-03h) 00 (00h) 00
EX6 Think chip-Slice LEVEL 0-255 (00h-FFh) 54 (36h) 12
EX7 RLYDELAYTIME 0-255 (00h-FFh) 00 (00h) For the power control 00
EX8 ADG ON TIME 0-255 (00h-FFh) 10 (0Ah) For the power control 0A
B. SPECIAL SETTING
SERVICE
NUMBER
DATA
ADJUSTMENT ITEM
INITIAL VALUE
NOTES FIXED VALUE
(HEX)
RANGE
C. OPTION SETTING
OP1 OPTION1 0-255 (00h-FFh) 213 (D5h) D5
OP2 OPTION2 0-255 (00h-FFh) 60 (3Ch) 18
OP3 OPTION3 0-255 (00h-FFh) 143 (8Fh) 9C
SERVICE
NUMBER
DATA
ADJUSTMENT ITEM
INITIAL VALUE
NOTES FIXED VALUE
(HEX)
RANGE
D. SOUND ADJUSTMENT
M01 INPUT LEVEL 0-15 (00h-0Fh) 07 (07h)
M02 MTS VCO 0-63 (00h-3Fh) 38 (26h) 26
M03 FILTER 0-63 (00h-3Fh) 36 (24h) 24
M04 WIDEBAND 0-63 (00h-3Fh) 28 (1Ch)
M05 SPECTRAL 0-63 (00h-3Fh) 23 (17h)
D01 V POSITION 0-7 (00h-07h) 00 (00h) 00
D02 H POSITION 0-31 (00h-1Fh) 15 (0Fh)
D03 V SIZE 0-127 (00h-7Fh) 89 (59h)
D04 H SIZE 0-63 (00h-3Fh) 36 (24h)
D05 V-LINEARITY 0-15 (00h-0Fh) 08 (08h)
D06 V-S CORRECTION 0-15 (00h-0Fh) 12 (0Ch) 0C
D07 EW PARABOLA 0-63 (00h-3Fh) 43 (2Bh)
D08 EW TRAPEZIUM 0-63 (00h-3Fh) 36 (24h)
D10 AFC GAIN 0-3 (00h-03h) 02 (02h) 02
D11V EHT 0-7 (00h-07h) 06 (06h) 06
D12 H EHT 0-7 (00h-07h) 06 (06h) 06
D13 EW CORNER 0-31 (00h-1Fh) 08 (08h) 08
D14 EW CORNER BOTTOM 19-81 (13h-51h) 50 (32h) 32
D15 NOISE DET LEVEL 0-3 (00h-03h) 00 (00h) 00
D18 V CENTERING 0-63 (00-3Fh) 36 (24h)
D19 V-AGC 0-1 (00h-01h) 00 (00h) 00
D20 V POSITION-VCOMP 0-7 (00h-07h) 00 (00h) 16:9 Format 00
D21 H POSITION-VCOMP 0-31 (00h-1Fh) 15 (0Fh) 16:9 Format
D22 V SIZE-VCOMP 0-127 (00h-7Fh) 52 (34h) 16:9 Format
D23 H SIZE-VCOMP 0-63 (00h-3Fh) 36 (24h) 16:9 Format
D24 V-LINEARITY-VCOMP 0-15 (00h-0Fh) 08 (08h) 16:9 Format 08
D25 V-S CORRECTION-VCOMP 0-15 (00h-0Fh) 10 (0Ah) 16:9 Format 0A
D26 EW PARABOLA-VCOMP 0-63 (00h-3Fh) 22 (16h) 16:9 Format
D27 EW TRAPEZIUM-VCOMP 0-63 (00h-3Fh) 35 (23h) 16:9 Format
D28 V EHT-VCOMP 0-7 (00h-07h) 06 (06h) 16:9 Format 06
D29 H EHT-VCOMP 0-7 (00h-07h) 06 (06h) 16:9 Format 06
D30 EW CORNER-VCOMP 0-31 (00h-1Fh) 12 (0Ch) 16:9 Format 0C
D31 EW CORNER BOTTOM-VCOMP 19-81 (13h-51h) 50 (32h) Offset toward D30 32
D32 V BLK UPPER-VCOMP 0-3 (00h-03h) 02 (02h) 16:9 Format 02
D33 V BLK LOWER-VCOMP 0-3 (00h-03h) 02 (02h) 16:9 Format 02
D34 V CENTERING-VCOMP 0-63 (00h-3Fh) 36 (24h) 16:9 Format 24
SERVICE
NUMBER
DATA
ADJUSTMENT ITEM
INITIAL VALUE
NOTES FIXED VALUE
(HEX)
RANGE
27SC26B
8

SERVICE ADJUSTMENT
RF AGC Adjustment
1. Receive a good local channel.
2. Enter the service mode and select the service
adjustment "R01".
3. Set the data value to point where no noise or beat
appears.
4. Select another channel to confirm that no noise or
beat appears.
Note 1 : You will have to come out of the service
mode to select another channel.
Note 2 : Setting the data to "00" will produce a black
raster.
Screen Adjustment
1. Receive a good local channel.
2. Enter the service mode and select the service
adjustment "V03" and set the data value to "00" to
set the color level to minimum. (Record original data
code under adjustment "V03" before changing) You
may skip this step, if you selected a B/W picture or
monoscope pattern.
3. Select the service adjustment "V11" and adjust the
data value to "01", this turn off the luminance signal
(Y-mute).
4. Adjust the master screen control until the raster
darkness to the point where raster is barely seen.
5. Adjust the service adjustments "V06" red, "V07" green
and "V08" blue to obtain a good grey scale with
normal whites at low brightness level.
6. Select the service adjustment "V11" and reset data
to "00". Select the service adjustment "V03" and reset
data to obtain normal color level.
7. For component input, the data value of "V46" red,
"V47" green and "V48" blue is adjusted to follow the
data value of "V06", "V07" and "V08" respectively.
8. For digital RF input, the data value of "V76" red, "V77"
green and "V78" blue is adjusted to follow the data
value of "V06", "V07" and "V08" respectively.
9. Reset the master screen control to obtain normal
brightness range.
AB
White Balance Adjustment
1. Receive a good local channel.
2. Enter the service mode and select the service
adjustment "V03" and set to "00" (minimum color)
(Record original data code under adjustment "V03"
before changing). "V03" does not have to be adjusted,
if you selected a B/W picture or monoscope pattern.
3. Alternately adjust the service adjustment data of "V09"
and "V10" until a good grey scale with normal whites
is obtained. (RF Input)
4. For component input, the data value of "V49" and
"V50" is adjusted to follow the data value of "V09"
and "V10" respectively.
5. For digital RF input, the data value of "V79" and "V80"
is adjusted to follow the data value of "V09" and "V10"
respectively.
6. Select the service adjustment "V03" and reset data
to obtain normal color level.
Sub-picture and Sub-Bright Adjustments
1. Receive the window pattern signal.
• RF INPUT (TU1101)
2. Get into service adjustment data "V01" and "V05" and
set the luminance as shown in figure "A" and "B" as
below respectively.
• COMPONENT INPUT
3. Get in service adjustment data "V42" and "V45" and
set the luminance as shown in figure "A" and "B" as
below respectively.
LUMINESCENCE CONFIRMATION
A: 86±10cd/m2
B: 1.25±0.5cd/m2
• DIGITAL RF INPUT (TU1101)
4. Get in service adjustment data "V72", "V75" and set
the luminance as shown in figure "A" and "B" as above
respectively.
NECESSARY UNNECESSARY
ADJUSTMENT
PART REPLACED
IC2001
IC201
XData is stored in IC2101.
The adjustment is needed to compensate for characteristics of parts
including IC201 and MTS level (M01).
Holding down both the VOL-up and CH-up buttons on the TV set at service mode for more than 2 seconds will
automatically write the above initial values into IC2101.
NOTES
X
IC2101
IC3001
CRT
Holding down both the VOL-up and CH-up buttons on the TV set in
the service mode for more than 2 seconds will automatically write the
above initial values into IC2101 Then perform a complete adjustment.
Adjust items related to picture tube only.
Adjust items related to MTS only (M01~M05).
X
X
X
27SC26B
9

Sub-Tint Adjustment
1. Receive the half color bar signal.
• RF INPUT (TU1101)
2. Get into Y-Mute by R/C, or by setting the "V11" bus
data to "01".
3. Vary the "V02" bus data until the waveform becomes
as stated below.
• Component Input and Digital RF Input (TU1101)
4. Input data of "V43" in 3E
5. Input data of "V73" in 47.
Sub-Color Adjustment
1. Receive a good local channel.
2. Make sure the customer color control is set to center
position .
• RF INPUT (TU1101)
3. Enter the service mode and select service adjustment
"V03".
4. Adjust "V03" data value to obtain a normal color level.
• Component Input
5. Repeat step 3~4, and change "V03" to "V44".
• Digital RF Input (TU1101)
6. Enter the service mode and select adjustment "V74".
7. Enter the value of "V44" data and plus (20h) or plus
32 step of "V44" data. (V74=V44+20h)
Focus Adjustment
1. Receive a good local channel.
2. Adjust the FOCUS VR of the flyback transformer to
make the image as fine as possible.
C. C Display Position Adjustment
1. Receive the lion head pattern signal.
2. Select "EX2" to display the text box.
3. Adjust the "EX2" bus data to let the text box displayed
in the center.
Vertical-Size and Linearity Adjustments
1. Receive a good local channel.
(SCREEN FORMAT 4:3)
DISPLAY OF TEXT BOX
TEXT BOX
AB
| A-B | / 2
SPEC INSPECTION:| A-B | / 2 <
=5mm
B-AMP Base waveform in step
(TP47B)
LEVEL
2. Enter the service mode and select the service
adjustment "D03" for V-size.
3. Adjust the "D03" bus data to get the proper V-size.
4. For V-linearity adjustment, select data bus "D05" and
adjust to get the proper vertical linearity.
(SCREEN FORMAT 16:9)
5. Input data of "D22" to mines 38 step from "D03” data.
(V-SIZE)
6. Input data of "D24" same as "D05" data. (V-LIN)
Note: Aging for 10 min before adjustment. After the
adjustment of V-center and V-size, re-
adjustment for this V-line.
Vertical Phase Adjustment
(SCREEN FORMAT 4:3)
1. Enter the service mode and input data of “00h” on
"D01".
2. Adjust "D18" data value so that picture is centered.
(SCREEN FORMAT 16:9)
3. Input data of "00h" on "D20".
4. Input data of "D34" same as "D18" data.
Horizontal Position Adjustment
1. Receive a good local channel.
(SCREEN FORMAT 4:3)
2. Enter the service mode and select the service
adjustment "D02".
3. Adjust "D02" data value so that picture is centered.
(SCREEN FORMAT 16:9)
4. Input data of "D21" same as "D02" data.
Horizontal-Size Adjustment
1. Receive a good local channel.
(SCREEN FORMAT 4:3)
2. Enter the service mode and select the service
adjustment "D04" for H-size.
3. Adjust the "D04" bus data to get the proper H-size.
(SCREEN FORMAT 16:9)
4. Input data of "D23" same as "D04" data.
EW-Parabola
1. Receive a good local channel.
(SCREEN FORMAT 4:3)
2. Enter the service mode and select the service
adjustment "D07" for EW parabola.
3. Adjust the "D07" bus data to get the proper vertical
straight line for both left and right side.
(SCREEN FORMAT 16:9)
4. Input data of "D26" to mines 21 step from "D07" data.
EW-Trapezium
1. Receive a good local channel.
(SCREEN FORMAT 4:3)
2. Enter the service mode and select the service
adjustment "D08" for EW-Trapezium.
3. Adjust the "D08" bus data to get the best position
display.
(SCREEN FORMAT 16:9)
4. Input data of "D27" same as "D08" data.
27SC26B
10

ËMTS ADJUSTMENT
MTS Level Adjustment
1. Set the sound volume above 1.
Monoral signal: 400Hz, 100% modulation
2. Confirm "EX4" data is "5Ah".
3. Vary the "M01" bus data until the voltage to pin (39)
of IC3001 to become the value as stated below.
SETTING VOLTAGE
ADJ spec : 490±10mVrms
CHK spec: 490±20mVrms
Separation Adjustment
1. Input "SIGNAL 1" and vary the "M04" bus data to get
the minimun AC voltage to pin (39) of IC3001.
2. Input "SIGNAL 2" and vary the "M05" bus data to get
the minimun AC voltage to pin (39) of IC3001.
SIGNAL 1: 300Hz, 30% modulation, Lch only, NR-ON
SIGNAL 2: 3kHz, 30% modulation, Lch only, NR-ON
Note: SIGNAL 1 Adj. for widebando
SIGNAL 2 Adj. for spectral
Check the output of the speaker at the maximum
volume as stated below.
Confirmation spec:
ADJ spec: above 25 dB
CHK spec: above 20 dB
27SC26B
11

CHASSIS LAYOUT
27SC26B
12

BLOCK DIAGRAM
27SC26B
13

DESCRIPTION OF SCHEMATIC DIAGRAMS
NOTES:
1. The unit of resistance "ohm" is omitted.
(K=kW=1000W, M=MW)
2. All resistors are 1/16 watt, unless otherwise noted.
3. All capacitors are µ F, unless otherwise noted.
(P=pF=µµF)
4. (G) indicates ±2% tolerance may be used.
5. indicates line isolated ground.
VOLTAGE MEASUREMENT CONDITIONS:
1. All DC voltages are measured with DVM connected
between points indicated and chassis ground, line
voltage set at 120V AC and all controls set for normal
picture unless otherwise indicated.
2. All voltages measured with 1000µ V B & W or Color
signal.
WAVEFORM MEASUREMENT CONDITIONS:
1. Photographs taken on a standard gated color bar
signal, the tint setting adjusted for proper color. The
wave shapes at the red, green and blue cathodes of
the picture tube depend on the tint, color level and
picture control.
2. indicates waveform check points (See chart,
waveforms are measured from point indicated to
chassis ground.)
WAVEFORMS
å AND SHADED ( ) COMPONENTS
= SAFETY RELATED PARTS.
ç MARK= X-RAY RELATED PARTS.
This circuit diagram is a standard one, printed circuits
may be subject to change for product improvement
without prior notice.
11.0 Vp-p 22.1 Vp-p 3 1.0Vp-p 40.75 Vp-p 55.0 Vp-p
65.0 Vp-p 70.85 Vp-p 812.5 Vp-p 932 Vp-p 056 Vp-p
q2.0 Vp-p w0.8 Vp-p e160 Vp-p r14 Vp-p t1150 Vp-p
y450 Vp-p u250 Vp-p i29.5 Vp-p o3.0 Vp-p p3.0 Vp-p
a3.0 Vp-p s130 Vp-p d125 Vp-p f130 Vp-p
27SC26B
14

654321
A
B
C
D
E
F
G
H
SCHEMATIC DIAGRAM: CRT Unit
15
27SC26B

A
B
C
D
E
F
G
H
10
98
7
6
5
4
3
2
1
SCHEMATIC DIAGRAM: MAIN-1 Unit
16
27SC26B

1716 1918151413121110
17
27SC26B

A
B
C
D
E
F
G
H
10
98
7
6
5
4
3
2
1
SCHEMATIC DIAGRAM: MAIN-1 Unit
18
27SC26B

1716 1918151413121110
19
27SC26B

A
B
C
D
E
F
G
H
10
98
7
6
5
4
3
2
1
SCHEMATIC DIAGRAM: MAIN-1 Unit
20
27SC26B