LG CS770 User manual

SPECIFICATIONS
1. PICTURE TUBE
Size : 17 inch
Gun : In-line
DefIection Angle : 90¡
Neck Diameter : 29.1 mm
Phosphor : P22
Transmission : 52%
Dot Pitch : 0.28 mm
Low Radiation : MPR-II, TCO-92
2. SIGNAL
2-1. HORIZONTAL & VERTICAL SYNC
1) Input Voltage Level : Low=0~0.8V, High=2.1~5.5V
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 ohm
3) Video Color : R, G, B Analog
4) Signal Format : Refer To Timing Chart
2-3. SIGNAL CONNECTOR
15 Pin D-Sub Connector
2-4. SCANNING FREQUENCY
Horizontal : 30 ~ 65 kHz
Vertical : 50 ~ 110 Hz
3. POWER SUPPLY
3-1. POWER RATING
AC 90 ~ 264V (Free Voltage), 50/60Hz, 1.5A Max.
3-2. POWER CONSUMPTION
4.DISPLAY AREA
4-1. Active Video Area : 300 mm X 225 mm
(Available for Full Screen)
4-2. Display Color : Full Colors
4-3. Display Resolution : 1280 Dots X 1024 Lines
(Non-Interlace)
4-4. Video Bandwidth : 100 MHz
5. ENVIRONMENT
5-1. Operating Temperature: 10 ~ 35¡C
(Ambient)
5-2. Relative Humidity : 8 ~ 80%
(Non-Condensing)
5-3. Altitude : 10,000 ft
6. DIMENSIONS (WITH TILT/SWIVEL)
Width : 412.0 mm
Depth : 431.0 mm
Height : 428.5 mm
7. WEIGHT (WITH TILT/SWIVEL)
Net. Weight : 17.0 kg
Gross Weight : 20.5 kg
- 2 -
MODE
NORMAL (ON)
STAND-BY
SUSPEND
OFF
H/V SYNC
ON/ON
OFF/ON
ON/OFF
OFF/OFF
POWER CONSUMPTION
less than 110 W
less than 15 W
less than 15 W
less than 5 W
LED COLOR
GREEN
ORANGE
GREEN/ORANGE
BLINKING
StudioWorks 76i : Comply with the MPR-II Requirement.
StudioWorks 76T : Comply with the TCO-92 Requirement.
76W : No Brand Model (MPR-II)

- 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 LG Electronics 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 25kV. 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 CRT 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.
SAFETY PRECAUTIONS

- 4 -
VIDEO
SYNC
C
E
D
F
A
B
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
31.467
31.778
25.422
6.356
0.636
3.813
1.907
59.941
16.683
15.253
1.430
0.318
0.063
1.049
640
480
Yes
MODE 1
31.467
31.778
25.422
6.356
0.636
3.813
1.907
70.077
14.270
12.711
1.559
0.415
0.064
1.080
720
400
Yes
MODE 3
37.500
26.667
20.317
6.350
0.508
2.032
3.810
75.000
13.333
12.800
0.533
0.026
0.080
0.427
640
480
Yes
MODE 4
46.875
21.333
16.162
5.171
0.323
1.616
3.232
75.000
13.333
12.800
0.533
0.021
0.064
0.448
800
600
Yes
MODE5
56.476
17.707
13.653
4.053
0.320
1.813
1.920
70.069
14.272
13.599
0.672
0.053
0.106
0.513
1024
768
Yes
MODE 6
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
768
Yes
MODE7
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
1024
Yes
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
TIMING CHART

POWER ON/OFF BUTTON
This button is used to turn the monitor on and off.
POWER INDICATOR
This indicator lights up green when the monitor
operates normally. If in stand-by or suspend mode, the
indicator color changes to blinking green and orange;
in off mode, changes to orange.
CONTRAST CONTROL
To adjust the image contrast level.
BRIGHTNESS CONTROL
To adjust the screen brightness level.
OSD SELECT / ADJUSTMENT
To select or adjust OSD menus.
OPERATING INSTRUCTIONS
- 5 -
FRONT VIEW
OSD ON/OFF
Enter button
OSD Select/Adjustment Control
AC Power Socket D-Sub Signal Connector
ID Label
Brightness Adjustment Control
Contrast Adjustment Control
Power (DPMS) Indicator
REAR VIEW
Power ON/OFF Switch
Front Control Panel
All functions are adjusted from the microprocessor based digital controls.
Increase
Decrease
Increase
Decrease
OSD ON/OFF Enter Button
OSD Select/Adjustment Control
Brightness
Contrast
Power Indicator
Power Button

- 6 -
ENTER BUTTON
Use this button to start/enter and exit from the On Screen
Display (OSD). If there is no OSD on the screen, one click
(press) of this button will show the Main Menu. To remove
the display, either wait 4~5 seconds or double click this
button. If you are in a Sub-menu, a single click will back
you out to the Main Menu.
On Screen Display (OSD) Control Adjustment
Making adjustment to the image size, position, and
operating parameters of the monitor are quick and easy
with the On Screen Display control system, using only the
Enter button and Adjustment Control knob. A quick
example is given below to familiarize you with the use of
the controls. Following this section is an outline of the
available adjustments and selections you can make using
the OSD.
Example:
Note: (Monitor and PC should be ON, with an image or
prompt on the screen). One click (press) the Enter button,
present you with the Main Menu 1 of the On Screen
Display system, with the first item highlighted. The
main picture area will also show the selected icon and a
brief description (here H-POSITION). The OSD should look
like below:
If you one more click, you are able to adjust selected icon
(here H-POSITION). The display will look like below:
The bar graph shows you the current level of the selected
H-POSITION control. Use the Adjustment Control knob to
increase or decrease the level to fit the screen or your
desired. When you are finished, press the Enter ( )
button once to return to Main Menu 1 and rotate the
Adjustment Control knob to make another selection. If you
have finished using the OSD after you have returned to
Main Menu 1, you can double click the Enter button or
wait 4~5 seconds exit the OSD.
OSD Adjustment and Selection Items
In the previous section, you were introduced to the
procedure of selecting and adjusting an item using the
OSD. There are four Main Menu pages; the first page has
4 most commonly use items.
Listed below are the icons, icon names, and descriptions
of the items that are shown on the Main Menu 1 OSD:
Horizontal Position. (To move picture image left and right.)
Horizontal Size. (To adjust image width.)
Vertical Position. (To move image up and down.)
Vertical Size. (To adjust image height.)
Listed below are the icons, icon names, and descriptions
of the items that are shown on the Main Menu 2 OSD:
Zoom. (To adjust H and V image size simultaneously.)
Side-Pincushion. (To correct the bowing in and out of
the image.)
Trapezoid. (To correct geometric distortion.)
Rotation. (To adjust tilt.)
Listed below are the icons, icon names, and descriptions
of the items that are shown on the Main Menu 3 OSD:
Degauss. (Used to demagnetize the picture to give
a more accurate image and color.)
Recall. (To recall the factory preset mode.)
Help. (To inform users of preset and user mode data.)
Listed below are the icons, icon names, and descriptions
of the items that are shown on the Main Menu 4 OSD:
Color Code. (To select color temperature, 9300¡£K/
7200¡£K/user.)
RGB Adjust. (To adjust individual R, G, B color at
user color code.)
H-POSITION
H-SIZE
V-POSITION
V-SIZE
H-POSITION
H-SIZE
V-POSITION
V-SIZE
50

H/ SINK
FBT
MAIN
VIDEO
11
10
9
12
13
14
8
1
2345 6
7
SW206
SW205 SW204 SW203 SW202
VR201
SW701
VR901
SW201
VR702
VR501
VR701
VR301
VR302
CONTROL
No.
1
2
3
4
5
6
7
No.
8
9
10
11
12
13
14
Ref. No.
SW206
SW205
SW204
SW203
SW202
VR201
SW201
Ref. No.
VR901
VR702
VR701
VR501
SW701
VR302
VR301
Control Function
POWER SWITCH
CONTRAST INCREASE
CONTRAST DECREASE
BRIGHTNESS INCREASE
BRIGHTNESS DECREASE
OSD SELECT
ENTER
Control Function
B+ADJUSTMENT
H-LIN. ADJUSTMENT
HIGH-VOLTAGE ADJUSTMENT
SUB-BRIGHT ADJUSTMENT
H-RASTER CENTER SW.
R CUT-OFF (R-BIAS)
G CUT-OFF (G-BIAS)
- 7 -
CONTROL LOCATIONS

P901 P501
Signal Cable
AC Socket
P403
P401
P402
P404
W3 W2
P601
P701
P201 P202 P203
SW701
P304
P305
P303
FBT
P302
P301
- 8 -
WIRING DIAGRAM

P901 P501
Signal Cable
AC Socket
P403
P401
P402
P404
W3 W2
P601
P701
P702
P201 P202 P203
SW701
P304
P305
P303
FBT
P302
P301
- 9 -
WIRING DIAGRAM (TCO-92)

- 10 -
DISASSEMBLY
1. TILT/SWIVEL REMOVAL
Set the monitor face down.
Pressing the latch , carefully remove the Tilt/Swivel
by pulling it upward.
2. BACK COVER REMOVAL
Remove four screws from the Back Cover.
Slide the Back Cover away from the Front Cabinet
of the monitor.
3. TOTAL CHASSIS ASSEMBLY REMOVAL
Disconnect P901 (Degaussing pin), P701
(H-DY pin), and P601 (V-DY pin).
Remove two screws from the Rear Bracket to
remove the Ground Wire of the CRT.
Remove two screws from the Main Bracket to
separate it from the Front Cabinet.

4. CRT BOARD ASSEMBLY REMOVAL
Remove three pins .
Remove CRT ground connector
Carefully separate the CRT Board Assembly from
the CRT neck.
Discharge the remaining static electricity by shorting
between the Anode Cap and the CRT ground.
Disconnect the Anode Cap from the CRT.
Anode Cap

- 11 -
5. BOTTOM BRACKET REMOVAL
Remove five screws .
Remove the Bottom Bracket.
6. MAIN BOARD ASSEMBLY REMOVAL
Remove five screws .
Remove three screws .
Release four latches from the Main Board
Assembly.
Bottom Bracket

BLOCK DIAGRAM
- 12 -

DESCRIPTION OF BLOCK DIAGRAM
1. Line Filter & Associated Circuit.
This is used for suppressing noise of the 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
(TH902), and the relay (RL901).
This circuit eliminates abnormal color of the screen
automatically by degaussing the shadow mask in the CRT
when turning on the power switch.
When you need to degauss while using the monitor, select
(DEGAUSS) on the OSD menu.
3. SMPS (Switching Mode Power Supply).
This circuit is working in the condition of 110-240VAC
(50/60Hz).
The operation procedure is as follows:
1) AC input voltage is rectified and smoothed by the
bridge diode (D901) and the capacitor (C907).
2) The rectified voltage (DC voltage) 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 the 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 (D909, D912~D916) and operate the other
circuits. (Deflection, Video Amplifier, etc.)
4. Over Voltage Protection Circuit.
This circuit consists of the photo-coupler (IC902), the
programmable shunt regulator diode (IC903), and the
associated circuit. If the secondary voltage exceeds the
specified voltage, the current of the photo-coupler LED
flows excessively.Then, collector current of the photo-
coupler flows excessively and stops the oscillation of the
control IC (IC901). Consequently, the secondary voltage
drops to zero volts.
5. X-ray Protection.
If the high voltage of the FBT reaches up to 30kV
(abnormal state), OP amp (IC702) pin 7 comes to high
level. It charges high level at the X-ray protection pin of
IC701 (TDA4855) then, B-DRV (Pin 6) function of this IC
will be shut down, so high voltage will not be generated.
(In the normal state, the high voltage is about 25kV.)
6. Micom (Microprocessor) Circuit.
The operating procedure of the 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 from the H and V sync
signal.
3) The Micom controls each OSD function signals.
(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 itself automatically.
7. 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 TDA4855 (IC701) and the
associated circuit.
8. Oscillating Circuit for D/D Converter.
This circuit generates the saw-tooth wave which has the
horizontal period by taking the output of the TDA4855
(IC701).
9. D/D (DC to DC) Converter.
This circuit supplies DC voltage to the horizontal
deflection output circuit by decreasing DC 175V which is
the secondary voltage of the SMPS in accordance with
the input horizontal sync signal.
10. Side-Pincushion & Trapezoid Correcting Circuit.
This circuit improves the Side-pincushion and the
Trapezoid distortion by mixing parabola and saw-tooth
wave to the D/D converter which is used for the supply
voltage source (B+) of the horizontal deflection circuit.
11. Horizontal Deflection Output Circuit.
This circuit makes the horizontal deflection by supplying
the saw-tooth current to the horizontal deflection yoke.
12. High Voltage Output & FBT (Flyback Transformer).
The high voltage output circuit is used for generating
pulse wave to the primary coil of the FBT (Flyback
Transformer; T701). A boosted voltage (about 25kV)
appears at the secondary circuit of the FBT and it is
supplied to the anode of CRT. And there are other output
voltages such as the dynamic focus and the screen
voltage.
13. H-Linearity Correction Circuit.
This circuit corrects the horizontal linearity for each
horizontal sync frequency.
- 13 -

14. H-Raster Centering Circuit.
This circuit makes that the back raster stay in center of the
screen by adjusting the SW701.
15. Vertical Output Circuit.
This circuit takes the vertical ramp wave from the
TDA4855 (IC701) and performs the vertical deflection by
supplying the saw-tooth wave current to the vertical
deflection yoke.
16. Dynamic Focus Output Circuit.
This circuit takes H and V parabola waves from the
TDA4855 (IC701) and amplifies these waves to offer to
the FBT (T701).
17. H & V Blanking and Brightness Control.
This circuit eliminates the retrace line by supplying a
negative pulse wave to the G1 of the CRT. This circuit is
used for control of the screen brightness by changing the
DC level of G1.
18. Image Rotation Circuit.
This circuit corrects the tilt of the screen by supplying the
image rotation signal to the tilt coil which is attached to the
CRT near the deflection yoke.
19. OSD Circuit.
This circuit is used for performing the OSD (On Screen
Display) function.
When a user selects the Enter button and OSD
Select/Adjust control, the adjustment status displays on
the screen.
20. Video Pre-Amp Circuit.
This circuit amplifies the analog video signal from 0-0.7V
to 0-4V. This circuit is operated by taking the clamp, R, G,
B drives, and contrast signals from the Micom (IC401).
21. Video Output Amp Circuit.
This circuit amplifies the video signal which comes from
the video pre-amp circuit and amplified video signal is
applied to the CRT cathode.
- 14 -

GENERAL INFORMATION
All adjustments are thoroughly checked and corrected when
the monitor leaves the factory. Therefore, the monitor
should operate normally and produce proper color and
pictures upon installation.
However, several minor adjustments may be required,
depending on the particular location in which the monitor is
operated.
Carefully draw out the monitor from the carton and remove
all packing materials. Check and adjust all the customer
controls such as Brightness and Contrast to obtain a normal
picture.
Alignment appliances and tools.
- IBM compatible PC & Monitor.
- Programmable Signal Generator (eg. VG-819 made
by Astrodesign Co.)
- E(E)PROM with saved each mode data.
- Oscilloscope with probe.
- Alignment cable with adaptor.
- Digital Voltmeter.
- Software (Alignment program for this monitor).
- White Balance Meter.
- Luminance Meter.
AUTOMATIC DEGAUSSING / MANUAL DEGAUSSING
The degaussing coil is mounted around the CRT so that
external degaussing is normally unnecessary after turn on
the monitor. The monitor should be degaussing properly
upon installation.
If the monitor is moved or faced in a different direction, or
the chassis or parts of the cabinet become magnetized to
cause poor color purity, press (DEGAUSSING) on the
OSD menu.
ADJUSTMENT PROCEDURE & METHOD
Install the cable for adjustment such as figure 1 and run
the alignment program on the DOS for the IBM compatible
PC.
1. Adjustment for the B+ Voltage
Display cross hatch pattern at Mode 7.
Adjust D914 cathode voltage to 175 0.2V with
VR901.
2. Adjustment for the HIGH-VOLTAGE
Display cross hatch pattern at Mode 7.
Adjust D713 cathode voltage to 41 0.5V with
VR701.
3. Adjustment for the Horizontal Raster Center
Display cross hatch pattern at Mode 7.
Adjust the raster should be center of the screen with
SW701.
4. Adjustment for the Screen Image
Display cross hatch pattern at Mode 1.
Adjust H-SIZE as arrow keys to 300 2mm.
Adjust H-POSITION as arrow keys to center of the
screen.
Adjust V-SIZE as arrow keys to 225 2mm.
Adjust V-POSITION as arrow keys to center of the
screen.
Adjust S-PCC (Side-Pincushion) as arrow keys to
be the best condition.
Adjust TRAPEZOID as arrow keys to be the best
condition.
Display from Mode 2 to Mode 7 and repeat the
adjustments from no. to no. as stated above.
5. Adjustment for the White Balance and Luminance.
Set the White Balance Meter.
Press the (DEGAUSSING) on the OSD menu for
demagnetized CRT.
Display color 0,0 pattern at Mode 7.
Set Brightness and VR501 (Sub-Bright) volume to
max position.
Set Contrast to max and Sub-Contrast to center
position.
Set VR301 R-Bias) and VR302 (G-Bias) to min
position.
Adjust Screen control on the FBT to 0.1FL of the
raster luminance.
Adjust VR301 (R-Bias) and VR302 (G-Bias) to white
balance x=0.281 0.015 and y=0.311 0.015.
Adjust VR501 (Sud-Bright) to 0.3 0.1FL of the
raster luminance.
Display color 15,0 box pattern (70 70mm) at Mode 7.
Adjust R-DRIVE 1, G-DRIVE 1, and B-DRIVE 1 to
white balance x=0.281 0.003 and y=0.311 0.003
with arrow keys.
Save in the COLOR 1.
Adjust SUB-CONTRAST 1 to 55 1FL of the box
pattern luminance.
Adjust R-DRIVE 2, G-DRIVE 2, and B-DRIVE 2 to
white balance x=0.297 0.003 and y=0.320 0.003
with arrow keys.
Save in COLOR 2.
- 15 -
ADJUSTMENT

Parallel Port
Failed Monitor
IBM
Compatible PC
Adapter
Video
Signal Generator
Control Line
A
B
C
13
25
1
14
1
5
11
10 15
5V
61
5
11
10 15
6
A
B
C
4.7K
74LS06
4.7K
5V
4.7K
74LS06
4.7K
- 16 -
Figure 1, Cable Connection
Adjust SUB-CONTRAST 2 to 55 1FL of the box
pattern luminance.
Display color 15,0 full white patten at Mode 7.
Adjust ABL to 30 1FL of the luminance.
Exit from the program.
6.Adjustment for the Focus.
Set the Brightness and Contrast to max position.
Display H character in full screen at Mode 7.
Adjust Focus control on the FBT that focus should
be the best condition.

1. NO POWER
NO POWER
(POWER INDICATOR OFF)
TROUBLE IN
D901
TROUBLE IN FUSE
(F901)
TROUBLE IN
IC901, IC902
Q901 or Q902
TROUBLE IN
D909, D912~D916
TROUBLE IN
IC904 or IC905
CHECK
FUSE OK?
CHECK
C907 VOLTAGE?
(AC120V : 170VDC,
AC220V : 310VDC)
NO
YES
YES
YES
YES
NO
NO
NO
- 17 -
CHECK
IC901 PIN 1 WAVEFORM
(SQUARE WAVE COMES
OUT?)
CHECK
D909, D912, D913,
D914, D915, D916
VOLTAGE?
TROUBLE-SHOOTING GUIDE

- 18 -
2. NO CHARACTER
NO CHARACTER
CHECK
IC301 PIN 1 3, 5,
8, 10, 12,
9, 17 (8V)?
CHECK
IC301 PIN 2, 4, 6 ?
CHECK
IC301 PIN 15, 19, 22 ?
CHECK
R, G, B CATHODE
VOLTAGE?
CHECK
IC302 PIN 1, 6, 8 ?
TROUBLE IN
P303,
12V LINE
TROUBLE IN
PC SIGNAL,
P302,
SIGNAL CABLE
TROUBLE IN
IC301
TROUBLE IN
Q301, Q302, Q303
TROUBLE IN
D307 D312,
Q304 Q307
TROUBLE IN
CRT SOCKET
NO
YES
NO
NO
YES
YES
YES
YES
NO
NO

NO VIDEO
(POWER INDICATOR ON)
CHECK
POWER INDICATOR
GREEN or ORANGE
BLINKING?
CHECK
D713 CATHODE
VOLTAGE ?
(41V)
CHECK
G1 VOLTAGE?
(10 20V)
TROUBLE IN
Q712
TROUBLE IN
Q503
TROUBLE IN
Q501, Q502
NO DPM MODE
(NO H and/or V Sync)
ORANGE OR BLINKING
NO
GREEN
YES
YES
NO
- 19 -
3. NO RASTER

- 20 -
NO H-DEFLECTION
(ONE VERTICAL LINE)
CHECK
Q708
CHECK
B+ VOLTAGE
(175V)?
CHECK
Q510 EMITTER
WAVE FORM?
CHECK
T702 PIN 4
B+ VOLTAGE?
TROUBLE IN
Q708, D705
TROUBLE IN
175V LINE
TROUBLE IN
Q509, Q510
TROUBLE IN
Q511
TROUBLE IN
L502, T702, P701
NO
NO
YES
YES
YES
YES
NO
NO
4. NO HORIZONTAL DEFLECTION

UNBALANCED OF H-LIN.
- 21 -
CHECK
IC401 PIN 7, 8, 9?
CHECK
Q716, Q717, Q718, Q719,
Q720, Q721?
CHECK
Q722 EMITTER
VOLTAGE?
TROUBLE IN
IC401 (MICOM)
TROUBLE IN
Q716~Q721
TROUBLE IN
IC703, Q722, R762
TROUBLE IN
L703, D717
NO
NO
YES
YES
YES
NO
5. TROUBLE IN H-LINEARITY
HORIZONTAL Cs 0 Cs 1 Cs 2
FREQUENCY(f )
30~33kHz L L L
33.1~43kHz L H L
43.1~52kHz H H L
52.1~60kHz H L H
60.1~67kHz H H H
Cs SIGNAL TABLE
H