SHARP 20MR10 Diagram
20MR10
SER VICE MANUAL
S11O220MR10
COLOR TELEVISION
Chassis No. SN-010
P
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V
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MODEL
20MR10
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.
CONTENTS
Page
ELECTRICAL SPECIFICA TIONS ......................................................................................................... 1
IMPORTANT SER VICE SAFETY PRECAUTION ................................................................................. 2
LOCATION OF USER'S CONTROL ..................................................................................................... 4
INSTALLATION AND SER VICE INSTRUCTIONS ................................................................................ 5
CHASSIS LAYOUT ............................................................................................................................. 11
BLOCK DIAGRAM .............................................................................................................................. 12
SCHEMATIC DIAGRAMS ................................................................................................................... 13
PRINTED WIRING BOARD ASSEMBLIES ........................................................................................ 20
REPLACEMENT PARTS LIST ............................................................................................................ 23
PACKING OF THE SET ......................................................................................................................29
ELECTRICAL SPECIFICA TIONS
POWER INPUT .................................................... AC 120 V, 60 Hz
POWER RATING ................................................................... 69 W
PICTURE SIZE ........................................... 1,194cm2 (185sq inch)
CONVERGENCE ............................................................. Magnetic
SWEEP DEFLECTION .................................................... Magnetic
FOCUS ............................................... Hi-Bi-Potential Electrostatic
INTERMEDIATE FREQUENCIES
Picture IF Carrier Frequency..................................... 45.75 MHz
Sound IF Carrier Frequency...................................... 41.25 MHz
Color Sub-Carrier Frequency .................................... 42.17 MHz
(Nominal)
AUDIO POWER
OUTPUT RATING ..................................................... 1 W (RMS)
SHARP CORPORA TION
SPEAKER
SIZE ...................................................................... 8 cm (Round)
VOICE COIL IMPEDANCE ............................ 32 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
(EIA, Channel Plan U.S.A.)
Specifications are subject to change without
prior notice.
This document has been published to be used for after
sales service only.
The
1
contents
are
subject
to
change
without
notice.
20MR10
IMPORTANT SER VICE SAFETY PRECAUTION
Service work should be performed only by qualified service technicians who are thoroughly
familiar with all safety checks and the servicing guidelines which follow:
WARNING
1. For continued safety, no
should be attempted.
2. Disconnect AC power before servicing.
3. Semiconductor heat sinks are
hazards when the chassis is operating.
4. The chassis in this
which are separated by
isolated (hot) ground system is for the B+
regulator
isolated
and the secondary
transformer
To prevent electrical shock use an
transformer between the line cord and power
receptacle, when servicing this chassis.
4A 125V
ground
circuit
.
and
system
CAUTION: FOR CONTINUED
PROTECTION AGAINST A
RISK OF FIRE, REPLACE
ONLY WITH SAME TYPE 4A125V FUSE.
modification
receiver
insulating
the
horizontal
is
circuit
of any circuit
potential
material.
output
of
the
ground
high
has two
for the low B+
systems
The
voltage
circuit.
DC
voltages
voltage
isolation
shock
non-
The
SER VICING 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 picture 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
4. Handle the picture tube only when
shatterproof goggles and after discharging
high
picture
voltage anode
tube
by the neck.
completely
wearing
the
.
X-RADIATION AND HIGH VOLTAGE LIMITS
1. Be sure all service personnel are aware of
procedures and instructions covering X-radiation.
The only potential source of X-ray in current solid
state TV receivers is the
picture tube does not emit
radiation, if the high voltage is as specified in
"High Voltage Check" instructions.
It is only when high voltage is excessive that Xradiation is capable of penetrating the shell of the
picture
The important
voltage
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
-no higher. Operation at higher voltages may
a failure of the picture tube or high voltage circuitry
and; also,
radiation in exceeding of desirable levels.
When the high voltage regulator is operating properly
4.
there is no possibility of an X-radiation problem.
Every time a color chassis is serviced, the brightness
should be tested while
with a meter to be certain that the high voltage
not
correctly.
5. Do not use a picture tube other than that specified
or make
high voltage circuitry.
6.
When
on a
avoid being
Do
to locate the cause of
tube
including
precaution
below the
voltage should always be
under
exceed
unrecommended
troubles hooting
receiver
not
operate
certain conditions, may produce
the
specified
with
unnecessarily close to the receiver.
the
picture
the lead in the glass material.
maximum
monitoring
value
and taking test
excessive
receiver
excessive
tube. However, the
measurable
is to keep the
level specified.
kept
at the
the high
and
that
it
circuit
modifications
measurements
high
longer
than
voltage.
rated
is
is
the
X-Ray
the
high
value
cause
voltage
does
regulating
to
the
voltage,
necessary
2
IMPORTANT SER VICE SAFETY PRECAUTION
(Continued)
20MR10
BEFORE RETURNING THE RECEIVER
&
(Fire Shock Hazard)
Before returning the receiver to the user, perform
the following safety checks.
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 and 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.
Connect the resistor connection to all
parts having a return to the chassis (antenna, metal
cabinet, screw heads, knobs and control shafts,
escutcheon and 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 nonpolarized adapter plug must be used only for the
purpose of
Any
current
Any measurements not within the limits outlined
above indicate of a potential shock hazard and
corrective
instrument to the customer.
completing
measured
action
must be taken before
1.5k ohm
TEST PR OBE
these check.)
must
10W
0.15 F
not
exceed
exposed
0.5 milliamp.
returning
metal
the
SAFETY NOTICE
Many electrical and mechanical parts in television
recevers have special
These
inspection, nor can protection afforded by them be
necessarily
rated for higher voltage,
Replacement parts which have these special safety
characteristics are identified in this manual; electrical
components
and shaded areas in the Replacement Parts Lists and
Schematic Diagrams.
characteristics
increased
having such features are
safety-related
are often not
by using
replacement
wattage and etc.
characteristics.
evident
from visual
components
identified
by " "
!
TO EXPOSED
METAL PARTS
For continued protection, replacement parts must be
identical
substitute
safety characteristics as the factory recommended
replacement
create shock, fire,
to those used in the
replacement
parts shown in this service manual, may
parts
which
X-radiation
CONNECT TO
KNOWN EARTH
GROUND
original
or other hazards.
circuit. The use of
do not have
3
the
same
20MR10
LOCATION OF USER'S CONTROL
Front Panel
H
C
–
VOL
POWER VIDEO IN AUDIO
+
MENU
SENSOR AREA FOR
REMOTE CONTROL
POWER
Press On.
Press again Off.
Basic Remote Control Functions
POWER
Press On.
Press again Off.
REMOTE KEYPAD
Accesses any channel from keypad.
FLASHBACK
Returns to previous channel.
VOLUME UP/DOWN
(+) Increases sound.
(–) Decreases sound.
• In menu mode, changes or selects
the TV adjustments.
MUTE
Press Mutes sound.
Press again Restores sound.
• CLOSED CAPTION appears when
sound is muted.
C
POWER
–
H
V
O
L
+
MENU
VOLUME UP/DOWN
(+) Increases sound.
(–) Decreases sound.
G1339SB
VIDEO IN AUDIO IN TERMINALS
CHANNEL UP/DOWN
(
) Selects next higher channel.
( ) Selects next lower channel.
• Press both at the same time to
access the MAIN MENU screen.
Infrared Transmitter Window
INPUT
Press Switch to external video input
mode.
Press again Switch to TV mode.
CHANNEL UP/DOWN
( ) Selects next higher channel.
( ) Selects next lower channel.
• Moves the “
” mark of the MENU
screen.
MENU
Press Accesses MAIN MENU.
Press again Exits MAIN MENU.
DISPLA
Y
Press Displays receiving channel for
four seconds.
Press again Removes display.
• Temporarily displays receiving
channel when in Closed Caption
mode.
TV
4
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.
20MR10
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 PROTECT OR 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
accurate input voltage.
2.
Allow
for warm up and adjust all customer
for normal picture and sound.
3. Receive a good local channel.
4. Connect a
that the
5. Apply external 27.2V DC at TP653 by
external DC supply , TV must be shut of f.
6. T o
reset
a
short
sure that
7. If the
stop in step 5, the
the set is
digital
voltmeter
the
protector, unplug
circuit
between
normal
operation
returned
voltmeter
reads 21.4 ±1.5 V.
picture
of the
circuit
to the customer .
to TP653 and make sure
TP651
appears
horizontal
must be
transformer
the AC cord
and
TP652.
on the screen.
oscillator
repaired
controls
using
and
Now
does
before
for
an
make
make
not
HIGH VOL T AGE CHECK
High voltage is not adjustable but must be
to verify that the receiver is operating within
and efficient design limitations as specified checks
should be as follows:
1. Connect an accurate high voltage meter
ground
2. Operate
line voltage, with a strong air signal or a
tuned in test signal.
3. Enter the service mode and select the
adjustment
4. The
beam).
If a correct reading cannot be obtained, check
circuitry for
voltage test, make
and
receiver
voltage
anode of
"S03" and Bus data "01" (Y-mute on).
should
malfunctioning
picture
for at least 15 minutes at 120V
be
approximately
Y-mute of
tube.
26.0kV (at zero
components.
f to the normal mode.
checked
safe
between
AC
properly
service
After the
5
20MR10
For adjustments of this model, the bus data is converted to various analog signals by the D/A
converter
Note: There are still a few analog adjustments in this series such as focus and master screen voltage.
the steps below whenever the service adjusment is required.
To enter the service mode and exit service mode.
While
pressing
Now, the TV set is
To
exit
the service mode,
the Vol-up and Ch-up
switched
on and enters the service mode.
turn
the
television
buttons
at the
off by
sametime,
pressing
the
plug
the AC cord into a wall socket.
power
button.
1. Service mode.
Before
function
putting
in the
unit
into
video
the service mode,
adjustment
menu
check
to ensure
that
customer
customer
adjustments
control
are in
are in the
their
proper
normal
mode.
(reset) position.
Use the reset
2. Service number selection.
In the service mode, you will see the
3
SIGNAL, FIX VALUE as show in Figure A.
4
Window : DEF
D01
D03
D05
RETURN
2
D02
D04
D06
window
screen as window . There are 3 adjustment categories DEF,
DEF
SIGNAL
1
Window : SIGNAL
3
S01
S13
RETURN
S02
S12
circuit.
Follow
2
RETURN
Window : ADJUSTMENT CATEGORIES
RETURN
Window : FIX VALUE
RETURN NEXT
4
F01 F02
F13 F14
Figure A: ADJUSTMENT CATEGORIES
1
SERVICE MODE
DEF
SIGNAL
FIX VALUE
EEPR OM
NEXT
PREVIOUS
RETURN
FIX VALUE
F15 F16
F25 F26
RETURN PREVIOUS
Press CH UP/DOWN button for selection and enter by VOL UP or VOL DOWN.
Press CH UP/DOWN
to adjust the data
button
number
to
select
the
adjustment
for each categories.
item and VOL UP/DOWN
(OSD disturbance can be erased by R/C display key)
(Note: EEPROM – factory used only)
6
Below are the adjustments ranges and initial values for FIX VALUE category.
FIX VALUE
SER VICE
POSITION
F01 OPTION 1 00-FF B0 A0
F02 OPTION 2 00-FF 04 0C
F03 E-SAVE 00-3F 23 2A
F04 TUNER SETUP 00, 01 00 00
F05 R-TONE RD 00-7F 19 03
F06 R-TONE BD 00-7F 00 7C
F07 B-TONE RD 00-7F 00 00
F08 B-TONE BD 00-7F 12 04
F09 FM LEVEL 00-1F 0C 0C
F10 AFC GAIN 00, 01 00 00
F11 G DRIVE 00, 0F 0F 0F
F12 FBT BLK SW 00, 01 01 01
F13 V COMP 00-07 07 07
F14 OSD CONT 00-07 02 01
F15 SHARPNESS 00-3F 19 19
F16 FLT SYS 00-03 00 00
F17 KILLER OP 00-07 04 02
F18 Y PRI 00-03 00 00
F19 CORING 00-07 04 04
F20 DC REST 00-03 02 02
F21 BS START 00-03 01 01
F22 BS GAIN 00-03 01 01
F23 ABL START 00-07 00 00
F24 R/B ANGLE 00-0F 08 08
F25 H BLK R 00-07 04 03
F26 H BLK L 00-07 04 00
ADJUST ITEM
RANGE
Table - A
DATA
INITIAL VALUE
20MR10
(Hex)
Below are the ranges and initial values for each adjustment and in each categories.
DEF
SER VICE
POSITION
D01 H-PHASE 00-1F 0C
D02 V-SIZE 00-7F 40
D03 V-POSITION 00-3F 20 Must be "20"
D04 CC-POSITION 00-FF 1A
D05 V-LINEARITY 00-1F 10 Must be "18"
D06 V-S-CORRECTION 00-1F 10 Must be "0C"
ADJUST ITEM
RANGE
DATA
Table - B
INITIAL VALUE
ADJUSTMENT CONTENTS
SIGNAL
SER VICE
POSITION
S01 RF AGC 00-3F 14
S02 VIDEO LEVEL 00-07 03
S03 Y-MUTE 00-03 00
S04 SUB BIAS 00-FF 40 Must be "30"
S05 R-BIAS 00-FF 00
S06 G-BIAS 00-FF 00
S07 B-BIAS 00-FF 00
S08 R-DRIVE 00-7F 40
S09 B-DRIVE 00-7F 40
S10 CONTRAST 00-7F 5A
S11 TINT 00-7F 40
S12 COLOR 00-7F 40
S13 BRIGHTNESS 00-7F 40
ADJUST ITEM
RANGE
Note: Refer to the SERVICE ADJUSTMENT for each corresponding values.
DATA
Table - C
INITIAL VALUE
ADJUSTMENT CONTENTS
"01":Y-MUTE, "02":V-STOP&Y-MUTE
"03":Activate color killer
7
20MR10
Holding
write
down
both
the V
ol-up/Ch-down
the above initial values into IC2102 (IC2101).
PART REPLACED
IC2001
IC201
IC2102
(IC2101)
CRT
NECESSAR Y
ADJUSTMENT
X
X
X
If using
IC2101
If using
IC2102
buttons
on the TV set at
UNNECESSAR Y
X
service
Data is stored in IC2102 (IC2101).
The adjustment is needed to
of parts including IC201.
Holding down both the Vol-up/Ch-down
set in the service mode for more than 2 seconds will
automatically write the above initial values into IC2102
(IC2101).
Adjust
items related to
Table - D
R2101 R2102 R2103 R2104
––
––
mode
for
more
than 2 seconds
NOTES
compensate
picture
tube only.
will
automatically
for characteristics
buttons
on the TV
Table - E
8
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