LG EV700 User manual

COLOR MONITOR
SERVICE MANUAL
CAUTION
BEFORE SERVICING THE UNIT,
READ THE SAFETY PRECAUTIONS IN THIS MANUAL.
CHASSIS NO. : CA-65
MODEL: EV700, CG771B
ID LABEL: EV700A

CONTENTS
SPECIFICATIONS
- 2 -
SPECIFICATIONS ................................................... 2
SAFETY PRECAUTIONS ........................................ 3
TIMING CHART ....................................................... 4
OPERATING INSTRUCTIONS ................................ 5
CONTROL LOCATIONS ......................................... 7
WIRING DIAGRAM ................................................. 8
DISASSEMBLY ....................................................... 9
BLOCK DIAGRAM ................................................. 11
DESCRIPTION OF BLOCK DIAGRAM...................12
ADJUSTMENT ...................................................... 14
TROUBLESHOOTING GUIDE .............................. 16
PRINTED CIRCUIT BOARD................................... 26
EXPLODED VIEW...................................................30
REPLACEMENT PARTS LIST ............................... 32
PIN CONFIGURATION........................................... 51
SCHEMATIC DIAGRAM......................................... 58
1. PICTURE TUBE
Size : 17 inch (Flat Square Tube)
DefIection Angle : 90°
Neck Diameter : 29.1mm
Transmission : 52% (TSB: 80%)
Dot Pitch : 0.28mm
Face Treatment : AR-ASC (Anti-Reflection and
Anti-Static Coating)
Low Radiation : TCO-92
2. SIGNAL
2-1. Horizontal & Vertical Sync
1) Input Voltage Level: Low=0~1.2V, High=2.5~5.5V
2) Sync Polarity : Positive or Negative
2-2. Video Input Signal
1) Voltage Level : 0 ~ 0.7 Vp-p
a) Color 0, 0 : 0 Vp-p
b) Color 7, 0 : 0.467 Vp-p
c) Color 15, 0 : 0.7 Vp-p
2) Input Impedance : 75 Ω
3) Video Color : R, G, B Analog
4) Signal Format : Refer to the Timing Chart
2-3. Signal Connector
15-pin D-Sub Connector
2-4. Scanning Frequency
Horizontal : 30 ~ 70kHz
Vertical : 50 ~ 160Hz
3. POWER SUPPLY
3-1. Power Range
AC 100~240V (Free Voltage), 50/60Hz, 2.0A Max.
3-2. Power Consumption
4. DISPLAY AREA
4-1. Active Video Area : 315 x 230 mm (12.40" x 9.06")
(Available for Full Screen)
4-2. Display Color : Full Colors
4-3. Display Resolution : 1280 x 1024 / 60Hz
(Non-Interlace)
4-4. Video Bandwidth : 110MHz
5. ENVIRONMENT
5-1. Operating Temperature: 5°C ~ 40°C
(Ambient)
5-2. Relative Humidity : 5% ~ 90%
(Non-condensing)
5-3. Altitude : 10,000ft
6. DIMENSIONS (with TILT/SWIVEL)
Width : 415mm (16.34 inch)
Depth : 459mm (18.07 inch)
Height : 430mm (16.93inch)
7. WEIGHT (with TILT/SWIVEL)
Net Weight : 17.0kg (37.48 lbs.)
Gross Weight : 20.5kg (45.20 lbs.)
MODE
NORMAL (ON)
STAND-BY
SUSPEND
OFF
FAULT
H/V SYNC
ON/ON
OFF/ON
ON/OFF
OFF/OFF
OUT OF RANGE
POWER CONSUMPTION
less than 110 W
less than 15 W
less than 15 W
less than 15 W
less than 3 W
LED COLOR
GREEN
ORANGE
ORANGE
ORANGE

SAFETY PRECAUTIONS
- 3 -
SAFETY-RELATED COMPONENT WARNING!
There are special components used in this color monitor
which are important for safety. These parts are marked
on the schematic diagram and the replacement parts
list. It is essential that these critical parts should be
replaced with the manufacturer's specified parts to
prevent X-radiation, shock, fire, or other hazards. Do not
modify the original design without obtaining written
permission from Gateway Inc. or you will void the original
parts and labor guarantee.
CAUTION: No modification of any circuit should be
attempted.
Service work should be performed only after
you are thoroughly familiar with all of the
following safety checks and servicing
guidelines.
SAFETY CHECK
Care should be taken while servicing this color monitor
because of the high voltage used in the deflection circuits.
These voltages are exposed in such areas as the
associated flyback and yoke circuits.
FIRE & SHOCK HAZARD
An isolation transformer must be inserted between the
color monitor and AC power line before servicing the
chassis.
• In servicing, attention must be paid to the original lead
dress specially in the high voltage circuit. If a short
circuit is found, replace all parts which have been
overheated as a result of the short circuit.
• All the protective devices must be reinstalled per the
original design.
• Soldering must be inspected for the cold solder joints,
frayed leads, damaged insulation, solder splashes, or
the sharp points. Be sure to remove all foreign
materials.
IMPLOSION PROTECTION
All used display tubes are equipped with an integral
implosion protection system, but care should be taken to
avoid damage and scratching during installation. Use only
same type display tubes.
X-RADIATION
The only potential source of X-radiation is the picture tube.
However, when the high voltage circuitry is operating
properly there is no possibility of an X-radiation problem.
The basic precaution which must be exercised is keep the
high voltage at the factory recommended level; the normal
high voltage is about 26kV. The following steps describe
how to measure the high voltage and how to prevent
X-radiation.
Note : It is important to use an accurate high voltage
meter calibrated periodically.
• To measure the high voltage, use a high impedance
high voltage meter, connect (–) to chassis and (+) to
the CDT anode cap.
• Set the brightness control to maximum point at full
white pattern.
• Measure the high voltage. The high voltage meter
should be indicated at the factory recommended level.
• If the meter indication exceeds the maximum level,
immediate service is required to prevent the possibility
of premature component failure.
• To prevent X-radiation possibility, it is essential to use
the specified picture tube.
CAUTION:
Please use only a plastic screwdriver to protect yourself
from shock hazard during service operation.

TIMING CHART
- 4 -
VIDEO
SYNC
C
E
DFA
B
MODE FACTORY PRESET MODE
Resolution
Recall
H
O
R
I
Z
O
N
T
A
L
V
E
R
T
I
C
A
L
kHz
µs
µs
µs
µs
µs
µs
Hz
ms
ms
ms
ms
ms
ms
MODE 2
–
37.500
26.667
20.317
6.349
0.508
2.032
3.810
–
75.000
13.333
12.800
0.533
0.027
0.080
0.427
640
x
480
75Hz
Yes
MODE 1
–
31.469
31.778
25.422
5.720
0.318
3.813
1.589
–
59.940
16.683
15.253
0.922
0.064
0.064
0.794
640
x
480
60Hz
Yes
MODE 3
–
31.470
31.776
25.421
6.355
0.636
3.813
1.907
+
70.000
14.269
12.712
1.557
0.382
0.063
1.112
720
x
400
70Hz
Yes
MODE 4
+
37.879
26.400
20.000
6.400
1.000
3.200
2.200
+
60.317
16.579
15.840
0.739
0.026
0.106
0.607
800
x
600
60Hz
Yes
MODE 5
+
46.875
21.333
16.162
5.172
0.323
1.616
3.232
+
75.000
13.333
12.800
0.533
0.021
0.064
0.448
800
x
600
75Hz
Yes
MODE 6
–
48.363
20.677
15.754
4.923
0.369
2.092
2.462
–
60.004
16.666
15.880
0.786
0.062
0.124
0.600
1024
x
768
60Hz
Yes
MODE 7
+
60.023
16.660
13.003
3.657
0.203
1.219
2.235
+
75.029
13.328
12.795
0.533
0.017
0.050
0.466
1024
x
768
75Hz
Yes
MODE 8
+
63.981
15.630
11.852
3.778
0.444
1.037
2.296
+
60.020
16.661
16.005
0.656
0.016
0.047
0.594
1280
x
1024
60Hz
Yes
MODE 9
+
68.677
14.561
10.836
3.725
0.508
1.016
2.201
+
84.997
11.765
11.183
0.582
0.015
0.044
0.524
1024
x
768
85Hz
No
MARK
A
B
C
D
E
F
A
B
C
D
E
F
Sync Polarity
Frequency
Total Period
Video Active Time
Blanking Time
Front Porch
Sync Duration
Back Porch
Sync Polarity
Frequency
Total Period
Video Active Time
Blanking Time
Front Porch
Sync Duration
Back Porch
* 1~8 Mode: Preset Mode

OPERATING INSTRUCTIONS
- 5 -
FRONT VIEW REAR VIEW
AC Power Socket Signal Cable
ID Label
Power (DPMS) Indicator Power ON/OFF Button
1. Power ON/OFF Button
This button is used to turn the monitor ON and OFF.
2. Power (DPMS) Indicator
This indicator lights up green when the monitor
operates normally; in DPMS (Energy Saving) mode,
–stand-by, suspend, or off mode –its color changes
to orange.
3. OSD Select/Adjustment
Use this knob for selecting (highlighting) an OSD
icon and adjusting level of the selected menu.
Front Control Panel
2. Power (DPMS) Indicator 3. OSD Select/Adjustment 1. Power ON/OFF Button

- 6 -
On Screen Display (OSD) Control
To adjust an image size, position, and operating
parameters are quick and easy with the On Screen Display
control system, using the OSD Select/Adjustment
knob. A
quick example is given below to familiarize yourself with
use of the controls.
Example;
Note: (Monitor and PC’s power switch should be ON,
with an image or prompt on the screen). A single
press of the OSD Select/Adjustment knob will present
you the main menu as below:
To adjust this item, rotate the OSD Select/Adjustment
knob and push it at the point of the selected item.
The display will look like as below:
Listed below are icons, icon names.
800 x 600
H : 68.4 kHz V : 84.6 Hz
EXIT
OSD R
USER MORE
SELECT
:
NAVIGATE
:
HORIZONTAL
SIZE
800 x 600
H : 68.4 kHz V : 84.6 Hz
EXIT
OSD R
USER MORE
SELECT
:
ADJUST
:
Pincushion: To correct bowing in or out of the image.
Tilt: To correct the image rotation.
Parallelogram: To correct the geometric distortion.
Pincushion Balance:
To correct balance on each side distortion.
Moiré: To reduce moiré.
Moiréis caused by intreference the periodical
display pattern with the periodical dot screen.
Trapezoid: To correct the geometric distortion.
Degauss: Used to demagnetize the picture to give
a more accurate image and color.
Mode Recall: To recall factory preset mode.
R
Advanced Option: There are four kinds of options.
MORE
Color Select: To select color temperature or set
color level; 9300K / 6550K / USER.
Exit:
To make the OSD disappear on the screen.
Language Select:
To choose one of the five languages for the OSD menu.
EXIT
Information: There is information of video
modes-preset and user modes.
USER
OSD
OSD Manager: To adjust horizontal or vertical
position of the OSD image.
Icon Description
Horizontal Size: To adjust the image width.
Horizontal Position: To move the image left or right.
Vertical Size : To adjust the image height.
Vertical Position: To move the image up or down.
Contrast: To adjust the image contrast level.
Brightness: To adjust the screen brightness level.
Icon Description
Out of Frequency Range
When inputed video signal is not available, the message will
display as below:
Self Diagnosis
This monitor has a SELF DIAGNOSIS OSD feature that is
pops up when the signal cable is not connection between a
PC and a monitor. The message will be highlighted as
below.
MONITOR SELF TEST
YOUR MONITOR IS
WORKING CORRECTLY
CHECK COMPUTER POWER
AND MONITOR CABLE
OUT OF FREQUENCY
HF : 120.0kHz
VF : 110.0Hz
HF : 30-70kHz
VF : 50-160Hz
OPERATING FREQUENCY

- 7 -
CONTROL LOCATIONS
MAIN
CONTROL
FBT
34
5
2
1
No.
1
2
3
No.
4
5
Ref. No.
SW201
VR201
VR101
Ref. No.
VR701
VR901
Control Function
POWER SWITCH
OSD SELECT/ADJUSTMENT
TCO ADJUSTMENT
Control Function
HIGHT-VOLTAGE ADJUSTMENT
B+ADJUSTMENT

WIRING DIAGRAM
- 8 -
P201
P401 P102
P101
P501
P301P302
P702
P402
P902 P903
S+
S
P304
P303
P703
Signal
Cable
AC
Socket
FBT
CONTROL

DISASSEMBLY
- 9 -
1. TILT/SWIVEL REMOVAL
1) Set the monitor face downward.
2) Pressing the latch (a), carefully remove the
Tilt/Swivel by pulling it upward.
2. BACK COVER REMOVAL
1) Remove two screw caps (a).
2) Remove four screws (b).
3) Slide the Back Cover away from the Front
Cabinet of the monitor.
P301
P304
P302
(a)
(a)
(b)
(a)
(a)
(a)
4. VIDEO PCB ASSEMBLY REMOVAL
1)
Disconnect P301, P302, P304 from the Video PCB.
2) Remove two screws (a) from the Total Chassis
Assembly.
3) Remove the Total Chassis Assembly.
(a)
(a)
3. TOTAL CHASSIS ASSEMBLY REMOVAL
1) Disconnect P902 (Degaussing pin), P701, P601
(DY pin), and P501(Tilt pin).
2) Remove two screws (a) from the Total Chassis
Assembly.
3) Remove the Total Chassis Assembly.

- 10 -
5. BOTTOM BRACKET REMOVAL
1) Remove three screws (a).
2) Remove four screws (b).
3) Remove the Bottom Bracket.
6. MAIN BOARD ASSEMBLY REMOVAL
1) Remove three screws (a).
2) Remove three screws (b).
3) Release two latches (c) from the Main Board
Assembly.
(b)
(a)
(b)
(b)
(c)
(c)
(a)
Bottom Bracket

- 11 -
BLOCK DIAGRAM
POWER INPUT
100~240VAC
(50/60Hz)
Line
Fil er
Degaussing
Circui
SMPS
TRANS
(T901)
SMPS
CONTROL
(IC901)
DPM
CONTROL
CIRCUIT
160V
125V
70V
15V
12V
6.3V
5V
TILT
Con rol
Circui
6.3V
15V
E2PROM
(IC402)
5V
OSD IC
(IC303)
H-Sync Sig
V-Sync Sig
I2C DATA(SDA)
I2C CLOCK(SCL)
VIDEO
PRE-AMP
(IC302)
Signal
Cable R
G
B
VIDEO
MAIN AMP
(IC303)
8V REG.
(IC304)
8V
12V
CUT OFF
CONTROL
125V
8V
5V
H/V Sync Processor
( IC701 )
TDA4856 V-OUT
( IC601)
TDA4866
H-OUT
( Q706)
H-Lineari y
Correc ion
DC/DC Conver er
X-RAY
Pro ec ion
Circui
FBT
( T701 )
Dynamic
Focus
Circui
Au o
Beam
Limi
Ver ical Blanking,
Brigh ness Con rol
- 120V
40V
6.3V
D/D Feed Back
TCO
30V
12V 160V
15V
MICOM
(IC401)
SCL / SDA
H/V Sync,
PWM Con rol
Sig
12V
15V
160V
DY CDT
Hea er ( 6.3V )
I2C
I2C
I2C
H/V
Sync
G1
Screen
Dynamic Focus
S a ic Focus
H.V
R/G/B
Bias
R/G/B
Con ras
H-DRV
B-DRV
B+
15V
TILT
COIL
DEGAUSSING
COIL
I2C
VOLTAGE
FEEDBACK
12V
CONTRAST
BRIGHTNESS
H-SIZE
H-POSITION
V-SIZE
V-POSITION
S-PCC
TRAP
DEGAUSS
RECALL
ADVANCED OPTION
COLOR
LANGUAGE
INFORMATION
OSD POSITION
EXIT
<OSD DISPLAY> Sense

DESCRIPTION OF BLOCK DIAGRAM
- 12 -
1. Line Filter & Associated Circuit.
This is used for suppressing noise of power input line
flowing into the monitor and/or some noise generated in
this monitor flowing out through the power input line.
That is to say, this circuit prevents interference between
the monitor and other electric appliances.
2. Degauss Circuit & Coil.
The degauss circuit consists of the degaussing coil, the
PTC(Positive Temperature Coefficient) thermistor(TH901),
and the relay(RL901). This circuit eliminates abnormal
color of the screen automatically by degaussing the
shadow mask in the CDT during turning on the power
switch. When you need to degauss in using the monitor,
select DEGAUSS on the OSD menu.
3. SMPS(Switching Mode Power Supply).
This circuit is working of 90~264V AC(50/60Hz).
The operation procedure is as follows:
1) AC input voltage is rectified and smoothed by the
bridge diodes (D901~D904) and the capacitor
(C907).
2) The rectified voltage(DC) is applied to the primary
coil of the transformer(T901).
3) The control IC(IC901) generates switching pulse to
turn on and off the primary coil of the transformer
(T901) repeatedly.
4) Depending on turn ratio of the transformer, the
secondary voltages appear at the secondary coils of
the transformer(T901).
5) These secondary voltages are rectified by each
diode(D902, D922~D924, D926)) and operate other
circuit. (horizontal and vertical deflection, video
amplifier, ...etc.)
4. X-ray Protection.
I f the high voltage of the FBT reaches up to 29kV
(abnormal state), Q807 operates and IC401(MICOM) pin
11 come to low level. Then MICOM control IC701
(Deflection controller) to stop Horizontal drive pulse and
stop Horizontal Deflection.
5. Micom(Microprocessor) Circuit.
The operating procedure of Micom(Microprocessor) and
its associated circuit is as follows:
1) H and V sync signal is supplied from the signal
cable.
2) The Micom(IC401) distinguishes polarity and
frequency of H and V sync.
3) The Micom sets operating mode and offers the
controlled data. (H-size, H-position, V-size, ... etc.)
4) The controlled data of each mode is stored in itself.
5) User can adjust screen condition by each OSD
function. The data of the adjusted condition is stored
in EEPROM(IC402).
6. Horizontal and Vertical Oscillation.
This circuit generates the horizontal pulse and the vertical
pulse by taking the H and V sync signal.
This circuit consists of the TDA4856(IC701) and the
associated circuit.
7. Oscillating Circuit for D/D Converter.
This circuit generates the saw-tooth wave which has the
horizontal period by taking output of the TDA4856(IC701).
8. D/D(DC to DC) Converter.
This circuit supplies DC voltage to the horizontal
deflection output circuit by decreasing DC 160V which is
the secondary voltage of the SMPS in accordance with
the input horizontal sync signal.
9. Side-Pincushion & Trapezoid Correction Cirucit.
This circuit improves the side-pincushion and the
trapezoid distortion of the screen by mixing parabola and
saw-tooth wave to output of the horizontal deflection D/D
converter which is used for the supply voltage(B+) of the
deflection circuit.
10. Horizontal Deflection Output Circuit.
This circuit makes the horizontal deflection by supplying
the saw-tooth current to the horizontal deflection yoke.

- 13 -
11. High Voltage Output & FBT(Flyback Transformer).
The high voltage output circuit is used for generating
pulse to the primary coil of the FBT(Flyback Transformer
(T701)). A boosted voltage(about 26kV) appears at the
secondary of the FBT and it is supplied to the anode,
focus, and screen voltage of the CDT.
12. H-Linearity Correction Circuit.
This circuit corrects the horizontal linearity for each
horizontal sync frequency.
13. Vertical Output Circuit.
This circuit takes the vertical ramp wave from the
TDA4856(IC701) and performs the vertical deflection by
supplying the saw-tooth current to the vertical deflection
yoke.
14. Dynamic Focus Output Circuit.
This circuit takes the horizontal and the vertical parabola
waves from the TDA4856(IC701) and amplifies it to
maintain constant focus on center and corners in the
screen.
15. H& V Blanking and Brightness Control.
Blanking circuit eliminates retrace line by supplying
negative pulse to the G1 of the CDT. And Brightness
circuit is used for control of the screen brightness by
changing DC level of the G1.
16. Image Rotation (Tilt) Circuit.
This circuit corrects the tilt of the screen by supplying the
image rotation signal to the tilt coil which is attached near
the deflection yoke of the CDT.
17. Video Pre-Amp Circuit.
This circuit amplifies the analog video signal from 0-0.7V
to 0-4V. It is operated by taking the clamp, R, G, B drive
and contrast signal from the Micom(IC401).
18. Video Output Amp Circuit.
This circuit amplifies the video signal which comes from
the video pre-amp circuit and amplified it to applied the
CDT cathode.
19. TCO Circuit
Purpose of this circuit is cancelling low frequency
electromagnetic emission of the CDT. Anode of the CDT
ripple is sensed by sensor and amplified by inverting
OPAmp(IC101). This exactly opposite phase signal
emission has effect on cancelling CDT’s electromagnetic
emission.

ADJUSTMENT
- 14 -
GENERAL INFORMATION
All adjustment are thoroughly checked and corrected
when the monitor leaves the factory, but sometimes
several adjustments may be required.
Adjustment should be following procedure and after
warming up for a minimum of 30 minutes.
•Alignment appliances and tools.
- IBM compatible PC.
- Programmable Signal Generator.
(eg. VG-819 made by Astrodesign Co.)
- EPROM or EEPROM with saved each mode data.
- Alignment Adaptor and Software.
- Digital Voltmeter.
- White Balance Meter.
- Luminance Meter.
- High-voltage Meter.
AUTOMATIC AND MANUAL DEGAUSSING
The degaussing coil is mounted around the CDT so that
automatic degaussing when turn on the monitor. But a
monitor is moved or faced in a different direction, become
poor color purity cause of CDT magnetized, then press
DEGAUSS on the OSD menu.
ADJUSTMENT PROCEDURE & METHOD
-Install the cable for adjustment such as Figure 1and run
the alignment program on the DOS for IBM compatible PC.
-Set external Brightness and Contrast volume to max position.
1. Adjustment for B+ Voltage.
1) Display cross hatch pattern at Mode 9.
2) Adjust voltage to 160V
± 0.5Vdc with VR901.
2. Adjustment for High-Voltage.
1) Display cross hatch pattern at Mode 9.
2) Adjust FBT B+voltage to 25.8kV
± 0.1kVdc with
VR701.
3. Adjustment for Factory Mode (Preset Mode).
1) Display cross hatch pattern at Mode 1.
2) Run alignment program for EV700 on the IBM
compatible PC.
3) Power button of the monitor turn off →turn on.
4) COMMAND →START →Y(Yes) command.
5) DIST. ADJ. →TILT command.
6) Adjust tilt as arrow keys to be the best condition.
7) DIST. ADJ. →BALANCE command.
8) Adjust balance of side-pincushion as arrow keys to
be the best condition.
9) DIST. ADJ. →BALANCE command.
10) Adjust parallelogram as arrow keys to be the best
condition.
11) DIST. ADJ. →FOS. ADJ command.
12) Adjust V-SIZE as arrow keys to 230 ± 2mm.
13) Adjust V-POSITION as arrow keys to center of the
screen.
14) Adjust H-SIZE as arrow keys to 315 ± 2mm.
15) Adjust H-POSITION as arrow keys to center of the
screen.
16) Adjust S-PCC (Side-Pincushion) as arrow keys to be
the best condition.
17) Adjust TRAPEZOID as arrow keys to be the best
condition.
18) Display from Mode 1 to Mode 8 and repeat above
from number
12) to 17) .
19) PRESET EXIT →Y (Yes) command.
4. Adjustment for White Balance and Luminance.
1) Set the White Balance Meter.
2) Press the DEGAUSS on the OSD menu for
demagnetization of the CDT.
3)
Set Brightness and SUB-Brightness to Max position
(TSB CDT), SUB-Brightness to 70(decimal) (LGE CDT).
4) Display color 0,0 pattern at Mode 7.
5) COLOR ADJ. →LUMINANCE command of the
alignment program.
6) COLOR ADJ. →BIAS ADJ. command of the
alignment program.
7) Check whether blue color or not at R-BIAS and G-
BIAS to min position and B-BIAS to 0.15
± 0.01FL.
Check it's not blue color.
8) Adjust R-BIAS and G-BIAS command to x=0.281
±
0.01 and y=0.311 ± 0.01 on the White Balance Meter
with PC arrow keys.
9) Adjust SUB-Brightnesscommand to 0.7 ± 0.1FL of the
raster luminance.
10) Display color 15,0 box pattern (70x70mm) at Mode 7.
11) Set Contrast and SUB-Contrast to max position.
12) DRIVE ADJ command.
13) Set B-DRIVE to 155(170, LGE CDT) (decimal) at
DRIVE of the alignment program.
Initial
Data
TSB CDT
H-Top Corner
H-Bottom Corner
V-Linearity
LGE CDT
32 18
18
22
(Decimal)
98 98
ABL 150 160

- 15 -
Figure 1. Cable Connection
220
Monitor to be
adjusted
Video
Signal Generator
IBM
Compatible PC
Parallel Port
Power inlet (required)
Power LED
ST Switch
Power Select Switch
(110V/220V)
Control Line
Not used
RS232C
PARALLEL
V-SYNC POWER
ST
VGS MONITOR
E
E
V-Sync On/Off Switch
(Switch must be ON.)
F
F
A
A
B
B
C
C
1510
5
569
1
1
1
14
13
25
6
5V
5V
5V
4.7K
4.7K
4.7K
74LS06
74LS06
OFF ON
OFF
ON
11
14) Adjust R-DRIVE and G-DRIVE command to white
balance x=0.281
± 0.003 and y=0.311 ± 0.003 on the
White Balance Meter with PC arrow keys.
15) Adjust SUB-CONTRAST command to 51 ± 1FL of the
color 15,0 box pattern (70x70mm) luminance at
mode 7 and save in color 1.
16) Display color 15,0 full white patten at Mode 7.
17) COLOR ADJ. →LUMINANCE →ABL command.
18) Adjust ABL to 41 ± 1FL of the luminance.
19) Exit from the program.
5. Adjustment for Focus.
1) Set the Brightness and Contrast to max position.
2) Display H character in full screen at Mode 7.
3) Adjust two Focus control on the FBT that focus
should be the best condition.

TROUBLESHOOTING GUIDE
- 16 -
NO POWER
(POWER INDICATOR OFF)
TROUBLE IN
D901, D902, D903, D904
TROUBLE IN FUSE
(F901)
TROUBLE IN
IC901, IC902
TROUBLE IN
D920, D922, D923,
D924, D926
TROUBLE IN
IC923, IC925, Q922,
Q923, Q924, Q926
CHECK
FUSE OK?
CHECK
C907 VOLTAGE?
(AC120V: 170VDC,
AC220V: 310VDC)
NO
YES
YES
YES
YES
NO
NO
NO
CHECK
IC901 PIN 3
WAVEFORM
(SQUARE WAVE
COMES OUT?)
CHECK
D920, D922, D924,
D923, D926
VOLTAGE?
1. NO POWER

- 17 -
2. NO CHARACTER
NO CHARACTER
CHECK
IC302 PIN 7, 15, 18,
21(8V) ?
CHECK
IC302 PIN 6, 8, 10 ?
CHECK
IC302 PIN 16, 19, 22 ?
CHECK
IC303
PIN 1, 3, 5 ?
CHECK
IC303 PIN 6 (70V)
10 (12V) ?
TROUBLE IN
P302 12V LINE, IC304
TROUBLE IN
PC SIGNAL,
P301 SIGNAL CABLE
TROUBLE IN
IC302
TROUBLE IN
P302 12V LINE/70V LINE
TROUBLE IN IC303
NO
YES
NO
NO
YES
YES
YES
YES
NO
NO
CHECK
R, G, B CATHODE
VOLTAGE?
TROUBLE IN
R338~R341,
R344, R345, L302~L304,
D307~D310, D312, D313
TROUBLE IN
CDT SOCKET
YES
NO

- 18 -
NO VIDEO
(POWER INDICATOR ON)
CHECK
POWER INDICATOR
GREEN or ORANGE?
CHECK
D712 ANODE
(-120V)?
CHECK
G1VOLTAGE?
(-10~20V)
TROUBLE IN
D712
TROUBLE IN
D926, Q925 (6.3V)
TROUBLE IN
Q801~Q806
DPM MODE
(NO H and/or V SYNC)
ORANGE
NO
GREEN
YES
YES
NO
3. NO RASTER

- 19 -
4. NO HORIZONTAL DEFLECTION
NO H-DEFLECTION
(ONE VERTICAL LINE)
CHECK
Q706?
CHECK
B+ VOLTAGE
(160V)?
CHECK
T701(FBT) PIN 3
(31KHZ 70V,
69KHZ 140V) ?
CHECK
Q705 COLLECTOR
WAVEFORM?
TROUBLE IN
Q706
TROUBLE IN
160V LINE
TROUBLE IN
Q717, Q718, Q719,
D707
TROUBLE IN
Q705
TROUBLE IN
T701, P701
NO
NO
YES
YES
YES
YES
NO
NO

- 20 -
5. TROUBLE IN H-LINEARITY
UNBALANCED OF H-LIN.
CHECK
IC401
PIN 18, 19, 20?
CHECK
Q711~Q716?
CHECK
L703?
TROUBLE IN
IC401 (MICOM)
TROUBLE IN
Q711 ~ Q716
TROUBLE IN
L703
TROUBLE IN
L720, R744
NO
NO
NO
YES
YES
YES Cs SIGNAL TABLE
30K ~ 38.9K
39K ~ 47.4K
47.5K ~ 61.9K
62K ~ 70K
Cs1
L
L
L
H
Cs2
L
L
H
H
Cs3
L
H
H
H
HORIZONTAL
FREQUENCY(fH)