Acer AC511 SERIES User manual

SERVICE GUIDE
COLOR MONITOR
ACER AC511 SERIES
41AS551-ACER-E

1
THESE DOCUMENTS ARE FOR REPAIR SERVICE INFORMATION ONLY. EVERY
REASONABLE EFFORT HAS BEEN MADE TO ENSURE THE ACCURACY OF THIS
MANUAL; WE CANNOT GUARANTEE THE ACCURACY OF THIS INFORMATION
AFTER THE DATE OF PUBLICATION AND DISCLAIMS LIABILITY FOR CHANGES,
ERRORS OR OMISSIONS,
MANUFACTURE DATA :Feb-20-03

2
TABLE OF CONTENTS
PAGE
1. SPECIFICATIONS ..................................................................................................... 3-4
2. PRECAUTION AND NOTICES ................................................................................ 5
2-1 SAFETY PRECAUTIONS .............................................................................. 5
2-2 PRODUCT SAFETY NOTICE ....................................................................... 5
2-3 SERVICE NOTES ........................................................................................... 5
2-4 HIGH VOLTAGE WARNING ....................................................................... 5-6
3. OPERATING INSTRUCTIONS ................................................................................ 6
4. ADJUSTMENT .......................................................................................................... 7
4-1 ADJUSTMENT CONDITIONS AND PRECAUTIONS ............................... 7
4-2 MAIN ADJUSTMENTS ................................................................................. 7
4-3 ADJUSTMENT METHOD ............................................................................. 7-9
5. CIRCUIT DESCRIPTION .......................................................................................... 10-12
6. TROUBLE SHOOTING CHART .............................................................................. 13
6-1 NO RASTER, CRT RELATIVE CIRCUIT PROBLEMS .............................. 13
6-2 ABNORMAL DISPLAY ................................................................................. 15
6-3 NO BLANKING .........................................................................................… 16
6-4 HOR. /OSC /DEF /HV CIRCUIT FAULT ...................................................... 16
6-5 ABNORMAL HORIZONTAL DEFLECTION .............................................. 17
6-6 ABNORMAL VERTICAL SCANNING ........................................................ 18
6-7 SIDE-PIN CUSHION DISTORTION ............................................................. 18
6-8 POOR FOCUS ................................................................................................. 19
6-9 NO SOUND (FOR AUDIO MODEL ONLY)..................................…........... 19
6-10 POWER SUPPLY TROUBLE SHOOTING CHART .................................... 20
7. MECHANICAL OF CABINET FRONT DIS-ASSEMBLY...................................... 21
8. PARTS LISTING ....................................................................................................... 22-43
9. BLOCK DIAGRAM (DEFLECTION) ....................................................................... 44
10. IC BLOCK DIAGRAMS............................................................................................ 46
11. PCB LAYOUT ............................................................................................................ 51
12. SCHEMATIC DIAGRAM ......................................................................................... 53

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1. SPECIFICATIONS FOR 5G SERIES COLOR MONITOR
1. CRT :
38cm(15V) 90 Deflection, 29mm Neck, 0.28mm Dot Pitch, Non-Glare Screen
2. Viewable image Size: 35cm (13.8") diagonal
3. Display Color: Unlimited Colors
4. External Controls:
Power On/Off, OSD key, Function knob: Contrast, Brightness, H-Size, H-Center, V-Size, V-Center, ZOOM,
Pincushion, Trapezoid, Rotation, Moire Reduce, Recall, Degaussing, Color Temperature.
5. Input Video Signal
Mode 1 Mode 2 Mode 3 Mode 4 Mode 5
R
GB Analog RGB Analog RGB Analog RGB Analog
R
GB Analog
Horiz. Sync: TTL Level TTL Level TTL Level TTL Level TTL Level
Negative Negative Negative Negative Positive
Vert. Sync: TTL Level TTL Level TTL Level TTL Level TTL Level
Positive Negative Negative Negative Positive
Horizontal: 720 (H) 640 (H) 640 (H) 800 (H) 1024 (H)
Vertical : 400 (V) 480 (V) 480(V) 600 (V) 768 (V)
Fh (KHz): 31.5 31.5 43.3 53.7 48.4
Fv(Hz) : 70 60 85 85 60
6. Display Size
Horizontal: 260 mm
Vertical: 195 mm
7. Scanning Frequencies
Horizontal: 30KHz ~54KHz
Vertical: 50 Hz ~120 Hz
8. Factory Preset Timings:7
User Timings: 8
9. Misconvergence
Center: 0.3 mm Max.
Corner: 0.4 mm Max.
10. Video Bandwidth: 65 MHz
11. Power Source:
Switching Mode Power Supply
AC 100 ~240V, 50/60Hz Universal Type
12. Operating Temperature: 0°C to 40°C Ambient
13. Humidity:
10% to 85% Relative, Non-Condensing
14. Weight: 11.5Kgs(Net), 13.0Kgs(Gross, China)
15. Dimensions Monitor:
Carton: 438(W) × 394(H) × 460(D)mm (China)
Monitor: 360(W) × 362(H) ×387(D)mm
16. External Connection:
15 Pin D-type Connector
AC Power Cord
17. Regulations:UL, CSA, FDA, FCC, TÜV/GS, CE, MPR-II,CCC

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2. PRECAUTIONS AND NOTICES
2-1 SAFETY PRECAUTIONS
1. Observe all caution and safety related notes located inside the display cabinet.
2. Operation of the display with the cover removed, may cause a serious shock hazard from the display
power supply. Work on the display should not be attempted by anyone who is not thoroughly familiar
with precautions necessary when working on high voltage equipment.
3. Do not install, remove or handle the picture tube in any manner unless shatter-proof goggles are worn.
People who are not so equipped should be kept away while handling picture tube. Keep picture tube away
from the body while handling.
4. The picture tube is constructed to limit X-RAY radiation to 0.5 MR/HR. For continued protection, use the
designated replacement tube only, and adjust the voltages so that the designated maximum rating at the
anode will not be exceeded.
5. Before returning a serviced display to the customer, a thorough safety test must be performed to verify
that the display is safe to operate without danger or shock. Always perform an AC leakage current check
on the exposed metallic parts of the cabinet, such as screw heads.
Test method for current leakage is described as follow.
(a) Plug the AC line cord directly into rated AC outlet (do not use a line isolation transformer during
this check).
(b) Use an AC voltmeter having 5000 ohms per volt or with more sensitivity in the following manner:
Connect a 1500 ohms 10 Watt resistor, paralleled by a 0.15UF, AC type capacitor between a known
good earth ground (water pipe, conduit, etc.) and the exposed metallic parts simultaneously.
Measure the AC voltage across the combination of 1500 ohms resistor and 0.15UF capacitor.
(c) Reverse the AC plug at the AC outlet and repeat AC voltage measurements for each exposed
metallic part.
(d) Voltage measured must not exceed 0.5 volts RMS. This corresponds to 0.35 milliamp AC. Any
value exceeding this limit constitutes a potential shock hazard and must be corrected immediately.
2-2 PRODUCT SAFETY NOTICE
Many electrical and mechanical parts in this chassis have special safety visual inspections and the protection
afforded by them cannot necessarily be obtained by using replacement components rated for higher voltage,
wattage, etc. Before replacing any of these components read the parts list in this manual carefully. The use of
substitute replacement parts which do not have the same safety characteristics as specified in the parts list may
create shock, fire, X-RAY radiation or other hazards.
2-3 SERVICE NOTES
1. When replacing parts or circuit boards, clamp the lead wires around terminals before soldering.
2. When replacing a high wattage resistor (more than 1/2W of metal oxide film resistor) in circuit board,
keep the resistor about 10mm (1/2 in) away from circuit board.
3. Keep wires away from high voltage or high temperature components.
4. Keep wires in their original position so as to reduce interference.
2-4 HIGH VOLTAGE WARNING
Operation of monitor outside of cabinet or with back removed may cause a serious shock hazard. Work on this
model should only be performed by those who are thoroughly familiar with precautions necessary when
working on high voltage equipment.
Exercise care when servicing this chassis with power applied. Many B plus and high voltage terminals are
exposed which, if carelessly contacted, can cause serious shock or result in damage to the chassis. Maintain
interconnecting ground lead connections between chassis and picture tube dag when operating chassis.
Certain HV failures can increase X-ray radiation. Monitor should not be operated with HV levels exceeding the
specified rating for the chassis type. The maximum operating HV specified for the chassis used in this monitor
is
24.0KV ±1KV
with a line voltage of 120/240 VAC. Higher voltage may also increase possibility of failure in HV supply.
It is important to maintain specified values of all components in the horizontal and high voltage circuits and
anywhere else in the monitor that could cause a rise in high voltage or operating supply voltages. No changes

5
should be made to the original design of the monitor. Components shown in the shaded areas on the schematic
should be replaced with exact factory replacement parts. The use of unauthorized substitute parts may create a
shock, fire or other hazard.
To determine the presence of high voltage, use accurate, high impedance, HV meter connected between second
anode lead and CRT dag grounding device. When servicing the High Voltage System, remove static charge
from it by connecting a 10K ohm resistor in series with an insulated wire (such as a test probe) between picture
tube dag and 2nd anode lead.(AC line cord disconnected from AC power outlet.)
The picture tube used in this monitor employs integral implosion protection. Replace with tube of the same
type number for continue safety. Do not lift picture tube by the neck. Handle the picture tube only after
discharging the high voltage completely.
3. OPERATING INSTRUCTIONS
This procedure gives you instructions for installing and using the 5E Color display.
1. Position the display on the desired operation and plug the power cord into a convenient AC outlet. Three-
wire power cord must be shielded and is provided as a safety precaution as it connects the chassis and
cabinet to the electrical conduit ground. If the AC outlet in your location does not have provisions for the
grounded type plug, the installer should attach the proper adapter to ensure a safe ground potential.
2. Connect the 15-pin color display shielded signal cable to your signal system device and lock both screws
on the connector to ensure firm grounding. The connector information is as follow:
15 - Pin Color Display Signal Cable
PIN NO. DESCRIPTION PIN NO. DESCRIPTION
1. RED 9. NC
2. GREEN 10. GND
3. BLUE 11. SYNC. GND
4. GND 12. SDA
5. GND 13. HORIZ. SYNC
6. GND-R 14. VERT. SYNC (＊VCLK)
7. GND-G 15. SCL
8. GND-B
3. Apply power to the display and allow about thirty seconds for display tube warm-up. The LED indicator
lights when the display is on.
4. With proper signals feed to the display, a pattern or data should appear on the screen, adjust the brightness
and contrast to the most pleasing display.
5. This monitor has power saving function following the VESA DPMS. Be sure to connect the signal cable
to the PC.
6. If your 5E Color display requires service, it must be returned with the power cord.
1
6
11 15
5
10

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4. ADJUSTMENT
4-1ADJUSTMENT CONDITIONS AND PRECAUTIONS
1. Approximately 30 minutes should be allowed for warm up before proceeding.
2. Adjustments should be undertaken only on those necessary elements since most of them have been
carefully preset at the factory.
4-2 MAIN ADJUSTMENTS
NO. FUNCTION LOCATION DESIGNATION
1. 15.0V ADJ PCB - MAIN VR901
2. B + ADJ PCB - MAIN VR902
3. SCREEN ADJ FLY BACK TRANS T402
4. FOCUS ADJ FLY BACK TRANS T402
5. ABL ADJ PCB - MAIN VR701
6. SUB-BRIGHTNESS ADJ PCB - MAIN VR702
-MENU PCB - MAIN SW103
-UP PCB - MAIN SW104
7. FUNCTION ADJ -DOWN PCB - MAIN SW103
-EXIT PCB - MAIN SW104
4-3 ADJUSTMENT METHOD
1. 15.0V, B + & HV voltage adjustment:
A. Chroma-2000 Signal generator or PC equivalent set mode2:, VGA 640X480 pattern 1.0 .
B. Connect a DC Volt meter between TP901 and ground, then adjust VR901 to be 15.0VDC.
C. Connect a DC Volt meter between TP902 and ground, then adjust VR902 to be 87 VDC.
2. Factory preset Timings Adjustment:
A. Press Encoder control Key to show OSD window then press again to switch the functional controls.
B. Select to the "ZOOM" function, then press the button While do not release until the OSD window
changed to the Factory preset window.
C. The Factory preset window contains the following functional controls. Select one of the control to adjust
its value for the optimum picture.
080
FACTORY PRESET
9300 6500
H:31.6 kHz V: 60Hz

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CONTRAST H-MOIRE REDUCE
BRIGHTNESS V-MOIRE REDUCE
H-CENTER R-GAIN
H-SIZE G-GAIN
V-CENTER B-GAIN
V-SIZE R-BIAS
ZOOM G-BIAS
PINCUSHION R-BIAS
TRAPEZOID 9300 COLOR TEMPERATURE
PIN-BALANCE 6500 COLOR TEMPERATURE
PARALLELOGRAM DEGAUSS
ROTATION OSD EXIT
RETURN
E. To switches the input signal to the other Timing Mode. Please follow step C ~ D to get the optimum
picture.
F. Select the " " RETURN function and press then the Factory Preset window will be returned to the
original OSD window.(user's operating condition)
G. The setting data of the CONTRAST, BRIGHTNESS, PIN-BALANCE, PARALLELOGRAM,
ROTATION, COLOR TEMPERATURE are common mode saved in the memory. Don't needed adjust it
individual at every timing Mode and save in the memory.
3. White Balance, Luminance adjustment:
A. Bias (Low Luminance) adjustment:
(a) Set mode 2 640×480 Fh: 31KHz full white pattern.
(b) To make the adjustment condition is under the Factory preset window.
Same as step 2-C.
(c) Warm up more than 20 minutes.
(d) Brightness set to maximum. Contrast set to min. full white pattern, then adjust FBT
screen VR to make Y= 5.0 ±0.5cd/m²
(e) Brightness set to raster just cutoff, adjust contrast to be 4FL, then adjust G-Bias , B-Bias
, R-Bias , to make the setting value is(50), then adjust the R.G.B Bias individual to
the color temperature x= 283 ±10, y= 297 ±10.
B. Gain (High light) adjustment:
(a) Set mode 2 640×480 Fh: 31.5KHz full white pattern.
(b) Brightness set to raster just cutoff and set the contrast to max.
(c) Adjust G-Gain , B-Gain , R-Gain , to make color temperature x=283 ±10,
y=297 ±10.
(d) Change to 20% window white pattern then adjust contrast to 155±2 cd/m².
C. Recheck item A&B to make sure both of them in spec. Finally select OSD function to the 9300°K
function, then press to make the setting data saved in the memory.

8
D. The adjustment of 6500°K white Balance, May follow step A ~ C , with the x=313 ±10, y=329 ±10.
E. Full white luminance:
(a) Set mode 2 640×480 Fh: 31.5KHz full white pattern.
(b) Image Size : H:260±4mm V:195±4mm.
(c) Brightness set to raster just cut off and set the contrast to max.
(d) Adjust VR701 to the luminance at 100 ±5cd/m².
4. Focus Adjustment:
A. Set mode 2 640×480 Fh: 53.8KHz with character full page.
B. Adjust brightness to center and contrast to max.
C. Then adjust focus VR to a fine vertical and horizontal line.
5. Purity Adjustment
A. Be sure that the display is not being exposed to any external magnetic fields.
B. Ensure that the spacing between the Purity, Convergence, Magnet, (PCM), assembly and the CRT stem is
29mm. (See below diagram)
C. Produce a complete, red pattern on the display. Adjust the purity magnet rings on the PCM assembly to
obtain a complete field of the color red. This is done by moving the two tabs in such a manner that they
advance in an opposite direction but at the same time to obtain the same angle between the two tabs,
which should be approximately 180'.
D. Check the complete blue and complete green patterns to observe their respective color purity. Make minor
adjustments if needed.
RELATIVE PLACEMENT OF TYPICAL COMPONENTS
Purity Magnets
Deflection Yoke
4-pole Convergence Magnets
6-pole Convergence Magnets
6. Convergence adjustment
A. Produce a magenta crosshatch on the display.
B. Adjust the focus for the best overall focus on the display.
Also adjust the brightness to the desired condition.
C. Vertical red and blue lines are converged by varying the angle between the two tabs of the 4 pole magnets
on the PCM assembly. (See above diagrams)
D. Horizontal red and blue lines are converged by varying the two tabs together, keeping the angle between
them constant.
E. Produce a white crosshatch pattern on the display.
F. Vertical green and magenta lines are converged by varying the angle between the two tabs of the 6-pole
magnets.
G. Horizontal green and magenta lines are converged by varying the two tabs together, keeping the angle
between them constant.

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5. CIRCUIT DESCRIPTION
5-1 MICRO CONTROLLER CIRCUIT
MICRO Controller
The IC101 contains a 6502 8-bit CPU core,256 bytes of RAM, 16K bytes of ROM,14 channel 8 bit PWM D/A
converters, 2 channel A/D converters for key detection, one 8 bit pre-loadable base timer, internal H-sync and
V-sync signals processor providing mode detection, watch- dog timer preventing system from abnormal operation,
and an I2C bus interface.
H/V sync signals processor
The functions of the sync processor include polarity detection, H-SYNC & V-SYNC signals counting,
Programmable SYNC signals output, free running signal generator. Pin39/Pin40 are for the H-SYNC and
V-SYNC input, Pin32/Pin33 will output the same signal as input sync signal without delay, and the polarity are
setting in the positive. When no signal input, the Pin32 will output a 61Hz V-SYNC free run signal. The Pin33
will output a 48KHz H-SYNC free run signal. for the monitor testing use.
On Screen Display Controller
The IC105 is designed for display the built-in characters or fonts onto monitor screen. The display operation is by
transforming data and control information from micro controller to RAM through a serial data interface.
Pin2 is used to control the internal oscillator frequency by DC voltage input from external low pass filter (R126,
C155) is used to regulate the appropriate bias current for internal oscillator the resonate at specific dot frequency.
Pin5 is input the horizontal fly back pulse, for PLL generator tracking.
Pin6 is left floating, I2C bus is enabled. Otherwise the SPI bus is enabled.
Pin7 the external data transfer through this pin to internal display registers and control registers
Pin8 the clock-input pin is used to synchronize the data transfer.
Pin18 is input the vertical flyback pulse for synchronizing the vertical position.
Pin20 is output a blanking signal to cut off external R.G.B signals of VGA while this chip is displaying characters
or windows.
Pin21, Pin22, Pin23 is used to output the OSD (B.G.R) video signal.

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5-2 DEFLECTION CIRCUIT
The deflection circuit is achieved by a high performance and efficient solution IC 401 (TDA9115) for this
monitor. The concept is fully DC controllable and can be used in applications with a micro-controller solutions.
The TDA9115 provides sync. Processing with full auto sync. Capability, a flexible SMPS block and an extensive
set of geometry control facilities. Further the IC generates the drive waveforms for DC coupled vertical boosters
to the TDA9302H.
Horizontal Oscillator
The oscillator is of the relaxation type and requires a capacitor of 1nF C446 at pin29. The maximum oscillator
frequency is determined by a resistor R403 4.7K form pin28 to ground.
PLL 1 Phase Detector
The phase detector is a standard one using switched current sources. It compares the middle of H-sync. with a
fixed point on the oscillator saw-tooth voltage. The PLL loop filter C401,R401,C402 is connected to Pin26.
PLL2 Phase Detector
This phase detector is similar to the PLL1 detector and compares the line flyback pulse at pin 1 with the
oscillator saw-tooth voltage. The PLL2 detector thus compensates for the delay in the external H-deflection
circuit by adjusting the phase of the HDRV output pulses. The phase between H-flyback and H-sync can be
controlled at pin30.
X-ray Protection
The X-ray protection input pin25 provides a voltage detector with a precise threshold. If the voltage exceeds this
threshold for a certain time, an internal latch switches the whole IC into protection mode. In this mode several
pins are forced into defined states:
Pin7 (BDRV) is floating
Pin6 (HDRV) is floating
Pin12, 13 ( VOUT 1, 2) are floating
Vertical Oscillator
The vertical free –running frequency is determined by the resistor R608 at pin23, with capacitor C604 at pin24.
Usually the free-running frequency should be lower than the minimum trigger frequency.

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5-3 TRANSISTOR & DIODE CIRCUIT
LOCATION CIRCUIT FUNCTION DESCRIPTION
D901 ~ D904 Bridge Rectifier for AC Source
D910 Clamp Diode for Snubber CKT
D919 Rectifier for Output Voltage
D922 Rectifier for Output Voltage
D923 Rectifier for Output Voltage
D925 Rectifier for Output Voltage
D927 Rectifier for Output Voltage
D929 Forward Bias when Q403 Turn-off to Protect B+ Block CKT
D930 B+ Feed Back Rectifier from F.B.T Pulse
Q907 Use for Off-Mode to Cut-off 6.3V Supply Voltage
Q909, Q910 Use for Standy-By or Suspend Mode to Cut-off 14.5V Supply Voltage
Q912, Q920 Push-Pull Topology to Drive Q911
Q913 Degaussing Switcher Transistor
Q921 5V Regulator Transistor
Q401 Turn-on at Power ON/OFF and Change Mode to Protect Hor.Block
Q402 HOR. Driver Transistor
Q407, Q408 As a Switcher for Horizontal s Correction CKT
Q409 H-Linear control transistor
Q411, Q410 Horizontal s correction control MOSFET
Q404, Q405 As Differential Amp. to Drive Q406
Q406 Darlington Transistor for H-Size Control
Q703 As a Switcher to Mute Screen
Q704, Q705 Brightness Control CKT
Q601, Q707 Blanking Signal output transistor

12
6.TROUBLE SHOOTING CHART
6-1 NO RASTER, CRT RELATIVE CIRCUIT PROBLEMS
REFER ITEM S.M.P.S.
BRIGHTNESS SET TO MAX. THEN
CHECK CRT G1 VOLTAGE
NG
NG
NG
NG
NG
OK
OK
OK
OK
OK
CHECK THE HIGE VOLTAGE
CHECK THE VOLTAGE OF CRT
HEATER ABOUT 6.3V
CHECK VOLTAGE OF THE CRT
CHECK BRIGHTNESS CIRCUIT
OK
CHECK POWER SAVING CIRCUIT,
"ABNORMAL DISPLAY"
H-SYNC, V-SYNC SIGNAL
CATHODE ABOUT 60V TO 70V
CHECK SCREEN VOLTAGE ABOUT
LESS THAN 300V CHECK FBT
CHECK MAIN PCB POWER SUPPLY
CHECK FAILSAFE CKT IC401
70V, 15V, 80V
Q909, Q910
CHECK CRT'S HEATER RELATIVE
CIRCUIT Q907, Q908
Q703, Q704, Q705 RELATIVE CKT.
PIN 25 RELATIVE CKT.
400V TO 600V
REFER ITEM 6-2
OF CRT ABOUT 23.5 ~ 25.5KV

13
2.ABNORMAL VIDEO LEVEL ON SCREEN
OK
NG
OK
NG
NG
OK
OK
CHECK THE VOLTAGE OF IC801
CHECK THE SIGNAL INPUT OF R.G.B.
ABOUT 0.7Vpp
CHECK THE VIDEO OUTPUT OF IC801
R.G.B. APPROACH STANDARD
CHECK SIGNAL CABLE OR
INTERFACE CARD.
CONTRAST SET MAX.
PIN 2, 16 ABOUT 8V
CHECK 8V RELATIVE CIRCUIT
CHECK THE IC801 PIN 11
RELATIVE CIRCUIT
RELATIVE CIRCUIT
CHECK IC801 PIN 11 CLAMP PULSE
PIN 13, 15, 18 ABOUT 4Vpp,
CHECK IC801 PIN 3/PIN 5/PIN 8 & PIN 10
3. ABNORMAL DDC (PLUG & PLAY)
OK
NG
CHECK IC101 PIN 5 VOLTAGE ABOUT 5V
CHECK SIGNAL CABLE
CHECK Q921 GOOD OR FAIL
OR H802 PIN 2, 3 DATA OUTPUT

14
6-2 ABNORMAL DISPLAY
1.NO SIGNAL ON SCREEN
CHECK FBT RELATIVE CIRCUIT
LESS THAN 400V
OK
NG
NG
OK
OK
NG
OK
NG
CHECK THE OUTPUT VOLTAGE
CHECK THE B+ VOLTAGE OF
CHECK THE VOLTAGE OF CRT
CATHODE ABOUT 40Vpp
CHECK THE VOLTAGE OF FBT SCREEN
CHECK THE RELATIVE CIRCUIT
CHECK THE 12V PIN
OF SMPS ON MAIN PCB
RELATIVE CIRCUIT
OF P802 CONNECTOR
ABOUT 400V TO 700V
EXCEED 700V CHECK FBT & CRT RELATIVE CIRCUIT
VIDEO PCB ABOUT 80V
CHECK THE 80V RELATIVE CIRCUIT
CHECK VIDEO IC801 VCC ABOUT 8V
OF IC801 PIN 13, 15, 18 ABOUT 3Vpp
CHECK THE IC802
OF IC801 PIN 2/PIN 16 Vcc CIRCUIT
OR REFER ITEM 6-1

15
6-3 NO BLANKING
NG
OK
CHECK THE RELATIVE
CIRCUIT OF BLANKING
CHECK THE RELATIVE CIRCUIT
CHECK G1 RELATIVE CIRCUIT
CHECK R859 ON VIDEO PCB,
FBT PIN 5 ON MAIN PCB
OF Q601, Q707
6-4 HOR./OSC/DEF/HV CIRCUIT FAULT
1. NO RASTER (DISCONNECT WITH SIGNAL CABLE)
NG
OK
OK
OK
NG
NG
NG
CHECK THE COLLECTOR VOLTAGE
CHECK THE COLLECTOR VOLTAGE
RELATIVE CIRCUIT
RELATIVE CIRCUIT
CHECK Q402, T401
CHECK T401, T402, Q402, Q403,
ABOUT 3Vpp
OF Q403 ABOUT 1200Vpp AT FH:31KHz
D408, C418, C419, H-DY, B+
CHECK IC401 PIN 26 WAVE FORM
CHECK IC401 PIN 4~7, PIN 13
CHECK IC401 PIN 29 ABOUT 12 VDC
CHECK IC401 PIN 29 RELATIVE CIRCUIT
OF Q402 ABOUT 20Vpp

16
6-5 ABNORMAL HORIZONTAL DEFLECTION
1. ABNORMAL HORIZONTAL WIDTH OF VIDEO
NG
OK
CHECK THE RELATIVE CIRCUIT
CHECK THE RELATIVE
CIRCUIT OF SMPS.
READJUST H-WIDTH FUNCTION
OF Q404, Q405, & Q406
CHECK THE HV OF
CHECK FBT B+ VOLTAGE
ABOUT 70V AT FH=31KHz
CRT ABOUT 24.5KV
2. ABNORMAL HORIZONTAL VIDEO CENTER
RELATIVE CIRCUIT
CHECK IC401 PIN 4, 7
3. ABNORMAL HORIZONTAL LINEARITY
AND IC101 PIN 28, 29
CHECK L401, Q410, Q426

17
6-6 ABNORMAL VERTICAL SCANNING
1. ABNORMAL VERTICAL SIZE
OK
NG
OK
NG
READJUST V-SIZE FUNCTION VALUE
RELATIVE CIRCUIT
CHECK VERT. OSC CIRCUIT
RELATIVE CIRCUIT
NG
READJUST V-SIZE FUNCTION VALUE
CHECK THE VOLTAGE OF IC101
RELATIVE CIRCUIT
CHECK IC401 PIN 20, 21, 22, 23
CHECK THE IC601 PIN 2 ABOUT 11.8V
PIN 4 ABOUT -12V
CHECK D601, C605
2. VERTICAL CENTER
NG
READJUST V-CENTER
RELATIVE CKT
CHECK IC401 AND IC601
6-7 SIDE-PIN CUSHION DISTORTION
NG
READJUST SIDEPIN
CHECK IC401, Q404, Q405, Q406
RELATIVE CKT.

18
6-8 POOR FOCUS
READJUST FOCUS CONTROL
NG CHECK FOCUS CONTROL UNIT,
FOCUS LEAD WIRE, CRT SOCKET & CRT
6-9 NO SOUND (OPTIONAL WITH AUDIO ONLY)
OK
OK
OK
OK
NG
ENSURE THE SOUND SOURCE
IS POWER ON
ENSURE THE SOURCE CABLE
CONNECTION
CHECK POWER
CHECK IC501
IC501 FAILURE
SPEAKER FAILURE
OK
SUPPLY CIRCUIT
ADJUST VOLUME CONTROL
NG
CHECK IC501
PIN 14 ABOUT 14V

19
6-10 POWER SUPPLY TROUBLE SHOOTING CHART
BEFORE CHECK SW.REG. PLEASE REFER TO THE POWER SUPPLY BLOCK DIAGRAM
POWER SUPPLY OUTPUT: (A) VARIABLE OUTPUT : 60.5V - 145V
(DEPENDING EPENDING UPON H.SYNC FREQUENCY)
(B) CONSTANT OUTPUT : 6.3V, 14.5V, -12V, 80V
BEAD SET ABNORMAL VARIABLE OUTPUT
NG
OK
NG
OK
OK
NG NG
NG
OK
OK
OK
NG
OK
NG
YES
NO
CHECK BRIDGE
RECTIFIED CIRCUIT
CHECK START C.K.T
CHECK IC401
CHECK D919
CHECK Q911
Q911 FAILURE
CHECK Q901
CHECK IC901
CHECK AC LINE
VOLT 120V OR 220V
CHECK F901, SW901
CHECK LINE RECTIFIED
& SMOOTHED VOLT
CHECK Q901
IC901 FAILURE
CHECK T901 O/P
MAKE SURE THAT
THE VARIABLE
OK
OUTPUT IS NOT SHORTED
R928, R932, D911, D917
CHECK THE 60V
PIN 14, 15, 16, 28, B+
DRIVER
6.3V, -12V CIRCUIT OUTPUT
IC401 29(ABOUT 11.5V)
CHECK 80V, 60V, 15V