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Contents
Contents . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
Safety Precautions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
Servicing Precautions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
Electrostatically Sensitive (ES) Devices . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
Description of Controls . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
Adjustment Instructions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
Correction of Screen Tilt & Keystone . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
Replacing the Lamp. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
Description of each Block Circuits . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
Description of Micom . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
Block Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33
Exploded View . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34
Exploded View Parts List . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35
Replacement Parts List . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36
Schematic Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
-2-
Safety Precautions
1. Before returning an instrument to the customer, always make a safety check High voltage is maintained within specified limits by close-tolerance safety-
of the entire instrument, including, but not limited to, the following items: related components/adjustments in the high-voltage circuit.
a. Be sure that no built-in protective devices are defective and/or have been If high voltage exceeds specified limits, check each component specified on
defeated during servicing. (1) Protective shields are provided on this chas- the chassis schematic and take corrective action.
sis to protect both the technician and the customer. Correctly replace all
missing protective shields, including any removed for servicing conve- 2. Read and comply with all caution and safety-related notes on or inside the
nience. (2) When reinstalling the chassis and/or other assemblies in the receiver cabinet, on the receiver chassis, or on the picture tube.
cabinet, be sure to put back in place all protective devices, including, but
not limited to, nonmetallic control knobs, insulating fishpapers, adjustment 3. Design Alteration Warning- Do not alter or add to the mechanical or elec-
and compartment covers/shields, and isolation resistor/capacitor networks. trical design of this TV receiver. Design alterations and additions, including,
Do not operate this instrument or permit it to be operated without all but not limited to, circuit modifications and the addition of items such as
protective devices correctly installed and functioning. auxiliary audio and/or video output connections, might alter the safety char-
acteristics of this receiver and create a hazard to the user. Any design alter-
b. Be sure that there are no cabinet openings through which an adult or child ations or additions will void the manufacturer's warranty and will make you,
might be able to insert their fingers and contact a hazardous voltage. Such the servicer responsible for personal injury or property damage resulting
openings include, but are not limited to, (1) spacing between the picture therefrom.
tube and the cabinet back, (2) excessively wide cabinet ventilation slots,
and (3) an improperly fitted and/or incorrectly secured cabinet back cover. 4. Picture Tube Implosion Protection Warning-The picture tube in this
receiver employs integral implosion protection. For continued implosion pro-
c. Antenna Cold Check-With the instrument AC plug removed from any AC tection, replace the picture tube only with one of the same type and num-
source, connect an electrical jumper across the two AC plug prongs. Place ber. Do not remove, install, or otherwise handle the picture tube in any
the instrument AC switch in the on position. Connect one lead of an ohm- manner without first putting on shatterproof goggles equipped with side
meter to the AC plug prongs tied together and touch the other ohmmeter shields. People not so equipped must be kept safely away while picture
lead in turn to each tuner antenna input exposed terminal screw and, if tubes are handled. Keep the picture tube away from your body. Do not han-
applicable, to the coaxial connector. If the measured resistance is less than dle the picture tube by its neck. Some "in-line" picture tubes are equipped
1.0 megohm or greater than 5.2 megohm, an abnormality exists that must with a permanently attached deflection yoke; because of potential hazard,
be corrected before the instrument is returned to the customer. Repeat this do not try to remove such "permanently attached" yokes from the picture
test with the instrument AC switch in the off position. tube.
d. Leakage Current Hot Check-With the instrument completely reassembled, 5. Hot Chassis Warning-a. Some TV receiver chassis are electrically con-
plug the AC line cord directly into a 120 V AC outlet. nected directly to one conductor of the AC power cord and may be safely
(Do not use an isolation transformer during this test.) Use a leakage current serviced without an isolation transformer only if the AC power plug is insert-
tester or a metering system that complies with American National Standards ed so that the chassis is connected to the ground side of the AC power
Institute (ANSI) C101.1 Leakage Current for Appliances and Underwriters source. To confirm that the AC power plug is inserted correctly, with an AC
Laboratories (UL) 1410, (50.7). With the instrument AC switch first in the on voltmeter measure between the chassis and a known earth ground. If a
position and then in the off position, measure from a known earth ground voltage reading in excess of 1.0 V is obtained, remove and reinsert the AC
(metal waterpipe, conduit, etc.) to all exposed metal parts of the instrument power plug in the opposite polarity and again measure the voltage potential
(antennas, handle bracket, metal cabinet, screwheads, metallic overlays, between the chassis and a known earth ground. b. Some TV receiver chas-
control shafts, etc.), especially any exposed metal parts that offer an electri- sis normally have 85 V AC (RMS) between chassis and earth ground
cal return path to the chassis. Any current measured must not exceed 0.5 regardless of the AC plug polarity. These chassis can be safely serviced
milliamp. Reverse the instrument power cord plug in the outlet and repeat only with an isolation transformer inserted in the power line between the
the test. receiver and the AC power source, for both personnel and test equipment
ANY MEASUREMENTS NOT WITHIN THE LIMITS SPECIFIED HEREIN protection. c. Some TV receiver chassis have a secondary ground system
INDICATE A POTENTIAL SHOCK HAZARD THAT MUST BE ELIMINAT- in addition to the main chassis ground. This secondary ground system is
ED BEFORE RETURNING THE INSTRUMENT TO THE CUSTOMER. isolated from the AC power line. The two ground systems are electrically
AC Leakage Test separated by insulating material that must not be defeated or altered.
(READING SHOULD
NOT BE ABOVE
0.5mA)
6. Observe original lead dress. Take extra care to assure correct lead dress in
LEAKAGE
DEVICE CURRENT the following areas: a. near sharp edges, b. near thermally hot parts- be
UNDER TESTER
TEST sure that leads and components do not touch, c. the AC supply, d. high
+ - voltage, and e. antenna wiring. Always inspect in all areas for pinched, out-
TEST ALL of-place, or frayed wiring. Do not change spacing between components,
EXPOSED MET AL
SURFACES and between components and the printed circuit board. Check the AC
power cord for damage.
2-WIRE CORD
ALSO TEST WITH EARTH 7. Components, parts, and/or wiring that appear to have overheated or are
PLUG REVERSED GROUND
(USING AC ADAPTER otherwise damaged should be replaced with components, parts, or wiring
PLUG AS REQUIRED)
that meet original specifications. Additionally, determine the cause of over-
e. X-Radiation and High Voltage Limits-Because the picture tube is the pri- heating and/or damage and, if necessary, take corrective action to remove
mary potential source of X-radiation in solid-state TV receivers, it is special- any potential safety hazard.
ly constructed to prohibit X-radiation emissions. For continued X-radiation
protection, the replacement picture tube must be the same type as the origi- 8. PRODUCT SAFETY NOTICE
nal. Also, because the picture tube shields and mounting hardware perform Some electrical and mechanical parts have special safety related character-
an X-radiation protection function, they must be correctly in place. istics which are often not evident from visual inspection, nor can the protec-
High voltage must be measured each time servicing is done that involves tion they give necessarily be obtained by replacing them with components
B+, horizontal deflection, or high voltage. Correct operation of the X-radia- rated for higher voltage, wattage, etc. Parts that have special safety charac-
tion protection circuits also must be reconfirmed each time they are ser-
viced. (X-radiation protection circuits also may be called "horizontal disable"
*
teristics are identified by shading, by a , or by on schematics and
parts lists. Use of a substitute replacement that does not have the same
or "hold-down.") Read and apply the high voltage limits and, if the chassis is safety characteristics as the recommended replacement parts might create
so equipped, the X-radiation protection circuit specifications given on instru- shock, fire, and/or other hazards. Product safety is under review continu-
ment labels and in the Product Safety & X-radiation Warning note on the ously and new instructions are issued whenever appropriate.
service data chassis schematic.
-3-
Servicing Precautions
CAUTION: Before servicing instruments covered by this service manual and 3. The components used in the unit have a specified flame resistance and
its supplements, read and follow the SAFETY PRECAUTIONS section of this dielectric strength. When replacing any components, use components
manual. Note: If unforeseen circumstances create conflict between the follow-
ing servicing precautions and any of the safety precautions, always follow the
which have the same ratings. Components identified by shading, by , or
by
*
in the circuit diagram are important for safety or for the characteristics
safety precautions. Remember: Safety First. of the unit. Always replace with the exact replacement components.
General Servicing Precautions 4. An insulation tube or tape is sometimes used and some components are
1. a. Always unplug the instrument AC power cord from the AC power source raised above the printed wiring board for safety. The internal wiring is some-
before: (1) removing or reinstalling any component, circuit board, module, times clamped to prevent contact with heating components. Install them as
or any other instrument assembly. (2) disconnecting or reconnecting any they were.
instrument electrical plug or other electrical connections. (3) connecting a
test substitute in parallel with an electrolytic capacitor in the instrument. 5. After servicing, always check that the removed screws, components, and
Caution: A wrong part substitution or incorrect polar-ity installation of wiring have been installed correctly and that the portion around the service
electrolytic capacitors may result in an explosion hazard. part have not been damaged. Further, check the insulation between the
b. Do not defeat any plug/socket B+ voltage interlocks with which instru- blades of the attachment plug and accessible conductive parts.
ments covered by this service manual might be equipped.
c. Do not apply AC power to this instrument and/or any of its electrical INSULATION CHECKING PROCEDURE
assemblies unless all solid-state device heat sinks are correctly installed. Disconnect the attachment plug from the AC outlet and turn the power on.
d. Always connect a test instrument's ground lead to the instrument chassis Connect the insulation resistance meter (500 V) to the blades of the attach-
ground before connecting the test instrument positive lead. ment plug. The insulation resistance between each blade of the attachment
Always remove the test instrument ground lead last. plug and accessible conductive parts (Note 1) should be more than 1 Mohm.
Note: Refer to the Safety Precautions section of this manual. Note: Accessible conductive parts include metal panels, input terminals, ear-
phone jacks, etc.
2. The service precautions are indicated or printed on the cabinet, chassis, or
components. When servicing, follow the printed or indicated service precau-
tions and service materials.
Electrostatically Sensitive (ES) Devices
Some semiconductor (solid-state) devices can be damaged eas- 5. Do not use freon-propelled chemicals. These can generate
ily by static electricity. Such components commonly are called electrical charge sufficient to damage ES devices.
Electrostatically Sensitive (ES) Devices. Examples of typical ES
devices are integrated circuits and some field-effect transistors 6. Do not remove a replacement ES device from its protective
and semiconductor "chip" components. The following techniques package until immediately before you are ready to install
should be used to help reduce the incidence of component dam- t.(Most replacement ES devices are packaged with leads elec-
age caused by static electricity. trically shorted together by conductive foam, aluminum foil, or
comparable conductive material.)
1. Immediately before handling any semiconductor component
or semiconductor-equipped assembly, drain off any electrosta- 7. Immediately before removing the protective material from the
tic charge on the body by touching a known earth ground. leads of a replacement ES device, touch the protective materi-
Alternatively, obtain and wear a commercially available dis- al to the chassis or circuit assembly into which the device will
charging wrist strap device, which should be removed for be installed.
potential shock reasons prior to applying power to the unit Caution: Be sure no power is applied to the chassis or circuit,
under test. and observe all other safety precautions.
2. After removing an electrical assembly equipped with ES 8. Minimize bodily motions when handling unpackaged replace
devices, place the assembly on a conductive surface such as ment ES devices. (Otherwise, seemingly harmless motion,
aluminum foil, to prevent electrostatic charge buildup or expo- such as the brushing together of your clothing or the lifting of
sure of the assembly. your foot from a carpeted floor, can generate static electricity
sufficient to damage an ES device.)
3. Use only a grounded-tip soldering iron to solder or unsolder
ES devices.
4. Use only an anti-static solder removal device. Some solder
removal devices not classified as "anti-static" can generate
electrical charges sufficient to damage ES devices.
-4-
Description of Controls
Main Body
ON/OFF
ON/OFF
ON/OFF Button
SOURCE MENU ENTER / VOL
MENU Button VOL F , G Button Indicators
SOURCE Button ENTER A / Button E,D Button
* Temperature indicator, lamp Indicator and operation indicator at the front of the monitor show the user the
operating status of the monitor.
Orange Standby.
Green(flashing) Lamp cooling untill the lamp turn on.
Operation Indicator (for 25 seconds)(Refer to P.18)
Green On operation.(Turn on the lamp)
Orange(flashing) Monitor lamp is cooling as power out(1 minutes)
Off Power off.
Monitor lamp is reaching the end of its life and needs
Red to be replaced with a new lamp.(over 10000 hours)
"Replace the Lamp"
Lamp Indicator
The monitor has trouble in the lamp or around it.
Red(flashing)
Contact the service center.
Green(flashing) The lamp cover is not closed.
Red The monitor is turned off due to its high temperature.
Contact your service center.
Temperature Indicator
Red(flashing) Power has turned off due to problem with the
Green(flashing) internal cooling fans. Contact your service center.
" " is the warning message on screen.
-5-
Rear Connecting Part
RGB IN3(DVI-I)
(12V/0.5A) S-VIDEO VIDEO
RGB IN1
DC OUT
RGB IN3
(DVI-I)
RGB IN2
RS-232C
RS-232C
PONENT
COM-
RGB OUT PR PB Y
R L
MOUSE
MIC
RS-232C RGB IN3(DVI-I)
DC OUT(12V/0.5A)
*Use this jack when
connecting the
wireless receiver to
(12V/0.5A) S-VIDEO VIDEO PONENT
RGB IN3(DVI-I)
DC OUT
RGB IN1
RGB IN1 the monitor.
S-VIDEO
RGB IN2 VIDEO
RGB IN2
RS-232C
COMPONENT
COM
PR PB Y
(Y, PB, PR)
R, L
RGB OUT
RGB OUT MOUSE
R L
MIC
MOUSE
MIC
-6-
Remote Control
POWER
POWER Button
SOURCE MENU
SOURCE Button MENU Button MOUSE DRAG
MOUSE DRAG
Button
L MOUSE Button L R
R MOUSE Button
(Zoom-out Button)
(Zoom-in Button)
ENTERA Button
POINTER Button
ZOOM Button MUTE Button
VOL. VOL. +, - Button
ZOOM MUTE * Switches the sound STILL
on or off. STILL Button
LASER Button ARC
LASER
ARC Button
AUTO
AUTO Button
AVL
AVL Button
DASP
DASP Button
APC
APC Button
MIC
MIC Button
Button Function
POWER Button Selects ON/OFF of power.
SOURCE Button Switches to RGB1/2/3, Video, S-Video, Component mode.
MENU Button Displays or hides the menu.
L MOUSE Button * Corresponds to the Left - Click of PC Mouse.
(Zoom-out Button) * Downsizes the screen on the zoom function.
R MOUSE Button * Corresponds to the Right - Click of PC Mouse.
(Zoom-in Button) * Enlarges the screen size on zoom function.
POINTER Button * After selecting menus, controls selecting and adjusting
functions with the direction of up, down, left, right.
* Moves the screen with the direction of up, down, left, right
on zoom function.
* Moves and releases the selected icon on PC screen.
MOUSE DRAG Button Uses to select and drag an icon in PC mode.
ENTERA Button Checks the present mode and sets the change of functions.
ZOOM Button Refer to page 34.
MUTE Button Cuts off audio.
VOL.(+, -) Button Adjusts volume level.
STILL Button
ARC Button
AUTO Button
AVL Button
DASP Button
APC Button
MIC Button
LASER Button Projects a bright red laser point on to the screen for indication
purposes.
(Don't look at laser beam directly as it will cause eye
damage.)
-7-
Accessories
POWER
SOURCE MENU
L R
ZOOM MUTE
LASER
1.5V
1.5V
Remote Control Batteries 2 (size AA) Audio/Video Cable
DVI cable Computer Cable Operating guide
Mouse Connecting Cables
PS/2 Mouse Cable MAC Serial Mouse Cable
(IBM PC or Compatible)
Optional Extras
* Contact your dealer for buying these items.
* Contact your dealer for replacing a new lamp.
S-Video Cable Lamp
-8-
Adjustment Instructions
1. Application Object 3) Adjust voltage of VREF and VMID for each R,G,B. ( SEE a
Table below)
This instruction is for the application to the LCD projection Monitor. 4) Press the ENTER key on the R/C for adjustment to store
the adjustment value when adjustment is finished.
2. Notes R G B Adj.Value
(1) The power source insulation of this LCD Projection TV is
VREF IC1808 PIn 14 The minimum value which is over 9.5V
not charging type and you may not use the transformer for
insulation. But you better adjust the set after operating it VMID IC1808 PIn1 7.0V
with insulation transformer between power supply cable
and input part of the set for protecting the adjusting equip-
ment. 4. EPLD Programming
(2) The adjustment must be performed under the correct
sequence.
(3) The adjustment must be performed in the circumstance of (1) Required Test Equipment
25!5