LG LM M533 Diagram
- 1-1 -
CONTENTS
SECTION 1. GENERAL
• SERVICING PRECAUTIONS
....................................................................................................................
1-2
• ESD PRECAUTIONS
.................................................................................................................................
1-4
• SPECIFICATIONS
.....................................................................................................................................
1-5
SECTION 2. ELECTRICAL
• ADJUSTMENTS
.........................................................................................................................................
2-1
• TROUBLESHOOTING
...............................................................................................................................
2-3
• CD PART VOLTAGE SHEET ................................................................................................................... 2-21
• CD PART WAVEFORMS OF MAJOR CHECK POINT
............................................................................
2-24
• BLOCK DIAGRAM
...................................................................................................................................
2-26
• SCHEMATIC DIAGRAMS
........................................................................................................................
2-28
• WIRING DIAGRAM
..................................................................................................................................
2-36
• PRINTED CIRCUIT DIARGAMS
..............................................................................................................
2-38
• INTERNAL BLOCK DIAGRAM OF IC’s
...................................................................................................
2-49
• REPAIRS REGARDING CD MECHANISM
.............................................................................................
2-55
SECTION 3. EXPLODED VIEWS
• CABINET AND MAIN FRAME SECTION
.................................................................................................
3-1
• TAPE DECK MECHANISM: AUTO STOP DECK(OPTIONAL)
..................................................................
3-3
• TAPE DECK MECHANISM: AUTO REVERSE DECK
................................................................................
3-5
• CD MECHANISM
........................................................................................................................................
3-7
SECTION 4. SPEAKER
..................................................................................................................
4-1
SECTION 5. REPLACEMENT PARTS LIST
..................................................................................
5-1
SECTION 1. GENERAL
❏ SERVICING PRECAUTIONS
NOTES REGARDING HANDLING OF THE PICK-UP
1. Notes for transport and storage
1) The pick-up should always be left in its conductive bag until immediately prior to use.
2) The pick-up should never be subjected to external pressure or impact.
2. Repair notes
1) The pick-up incorporates a strong magnet, and so should never be brought close to magnetic materials.
2) The pick-up should always be handled correctly and carefully, taking care to avoid external pressure and
impact. If it is subjected to strong pressure or impact, the result may be an operational malfunction and/or
damage to the printed-circuit board.
3) Each and every pick-up is already individually adjusted to a high degree of precision, and for that reason
the adjustment point and installation screws should absolutely never be touched.
4) Laser beams may damage the eyes!
Absolutely never permit laser beams to enter the eyes!
Also NEVER switch ON the power to the laser output part (lens, etc.) of the pick-up if it is damaged.
5) Cleaning the lens surface
If there is dust on the lens surface, the dust should be cleaned away by using an air bush (such as used
for camera lens). The lens is held by a delicate spring. When cleaning the lens surface, therefore, a
cotton swab should be used, taking care not to distort this.
6) Never attempt to disassemble the pick-up.
Spring by excess pressure. If the lens is extremely dirty, apply isopropyl alcohol to the cotton swab. (Do
not use any other liquid cleaners, because they will damage the lens.) Take care not to use too much of
this alcohol on the swab, and do not allow the alcohol to get inside the pick-up.
- 1-2 -
Storage in conductive bag
Drop impact
NEVER look directly at the laser beam, and don’t let
contact fingers or other exposed skin.
Magnet
How to hold the pick-up
Pressure
Pressure
Cotton swab
Conductive Sheet
NOTES REGARDING COMPACT DISC PLAYER REPAIRS
1. Preparations
1) Compact disc players incorporate a great many ICs as well as the pick-up (laser diode). These
components are sensitive to, and easily affected by, static electricity. If such static electricity is high
voltage, components can be damaged, and for that reason components should be handled with care.
2) The pick-up is composed of many optical components and other high-precision components. Care must
be taken, therefore, to avoid repair or storage where the temperature of humidity is high, where strong
magnetism is present, or where there is excessive dust.
2. Notes for repair
1) Before replacing a component part, first disconnect the power supply lead wire from the unit
2) All equipment, measuring instruments and tools must be grounded.
3) The workbench should be covered with a conductive sheet and grounded.
When removing the laser pick-up from its conductive bag, do not place the pick-up on the bag. (This is
because there is the possibility of damage by static electricity.)
4) To prevent AC leakage, the metal part of the soldering iron should be grounded.
5) Workers should be grounded by an armband (1MΩ)
6) Care should be taken not to permit the laser pick-up to come in contact with clothing, in order to prevent
static electricity changes in the clothing to escape from the armband.
7) The laser beam from the pick-up should NEVER be directly facing the eyes or bare skin.
CLEARING MALFUNCTION
You can reset your unit to initial status if malfunction occur(button malfunction, display, etc.).
Using a pointed good conductor(such as driver), simply short the RESET jump wire on the inside of the
volume knob for more than 3 seconds.
If you reset your unit, you must reenter all its settings(stations, clock, timer)
NOTE: 1. To operate the RESET jump wire, pull the volume rotary knob and release it.
2. If you wish to operate the RESET jump wire, it is necessary to unplug the power cord.
- 1-3 -
Armband
Conductive
Sheet
Resistor
(1 Mohm)
Resistor
(1 Mohm)
VOLUME KNOB
UP
DOWN
VOLUME
RESET jump wire
❏ ESD PRECAUTIONS
Electrostatically Sensitive Devices (ESD)
Some semiconductor (solid state) devices can be damaged easily by static electricity. Such components
commonly are called Electrostatically Sensitive Devices (ESD). Examples of typical ESD devices are integrated
circuits and some field-effect transistors and semiconductor chip components. The following techniques should
be used to help reduce the incidence of component damage caused by static electricity.
1. Immediately before handling any semiconductor component or semiconductor-equipped assembly, drain off
any electrostatic charge on your body by touching a known earth ground. Alternatively, obtain and wear a
commercially available discharging wrist strap device, which should be removed for potential shock reasons
prior to applying power to the unit under test.
2. After removing an electrical assembly equipped with ESD devices, place the assembly on a conductive
surface such as aluminum foil, to prevent electrostatic charge buildup or exposure of the assembly.
3. Use only a grounded-tip soldering iron to solder or unsolder ESD 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 ESD devices.
5. Do not use freon-propelled chemicals. These can generate electrical charges sufficient to damage ESD
devices.
6. Do not remove a replacement ESD device from its protective package until immediately before you are ready
to install it. (Most replacement ESD devices are packaged with leads electrically shorted together by
conductive foam, aluminum foil or comparable conductive materials).
7. Immediately before removing the protective material from the leads of a replacement ESD device, touch the
protective material to the chassis or circuit assembly into which the device will by installed.
CAUTION : BE SURE NO POWER IS APPLIED TO THE CHASSIS OR CIRCUIT, AND OBSERVE ALL OTHER
SAFETY PRECAUTIONS.
8. Minimize bodily motions when handing unpackaged replacement ESD devices. (Otherwise harmless motion
such as the brushing together of your clothes fabric or the lifting of your foot from a carpeted floor can
generate static electricity sufficient to damage an ESD device).
CAUTION. GRAPHIC SYMBOLS
THE LIGHTNING FLASH WITH APROWHEAD SYMBOL. WITHIN AN EQUILATERAL TRIANGLE, IS
INTENDED TO ALERT THE SERVICE PERSONNEL TO THE PRESENCE OF UNINSULATED
“DANGEROUS VOLTAGE” THAT MAY BE OF SUFFICIENT MAGNITUDE TO CONSTITUTE A RISK OF
ELECTRIC SHOCK.
THE EXCLAMATION POINT WITHIN AN EQUILATERAL TRIANGLE IS INTENDED TO ALERT THE
SERVICE PERSONNEL TO THE PRESENCE OF IMPORTANT SAFETY INFORMATION IN SERVICE
LITERATURE.
- 1-4 -
- 1-5 -
Power supply Refer to the back panel of the unit
General
Power consumption 75W
Net weight 7.7kg
Extemal dimensions(WxHxI) 273x330x360
Frequency Response 40Hz ~ 18000Hz
CD Signal-to-noise ratio 70dB
Dynamic range 70dB
Tuning Range FM1 87.50MHz ~108MHz or 65 ~ 74MHZ
FM
Intermediate Frequency 10.7MHz
Signal-to-noise ratio MONO : 60dB STEREO: 55dB
Frequency Response 60Hz ~ 10000Hz
Tuning Range 522KHz~1611kHz
(530kHz ~1610kHz)
AM Intermediate Frequency 450MHz
Signal-to-noise ratio 35dB
Frequency Response 100Hz ~ 1800Hz
OUtput Power 50W + 50W
AMP
T.H.D 0.15%
Frequency Response 40Hz ~ 25000Hz
Signal-to-noise ratio 80dB
Tape Speed 4.75(+2%, -1%)
Wow flutter 0.25%
F.F/REW Time 120sec(LIMIT)
Tape Frequency Response 125Hz ~ 8000Hz
Signal-to-noise ratio 43dB
channel separation 50dB
Erase Ratio 55dB
Type 5Way 5Speaker
Impedance 5Ω
Frequency Response 60~20000Hz
SPEAKER
Sound Pressure Level 5dB/W(1m)
Rated Input Power 50W
Max.Input Power 100W
net Dimension(WxHxD) 200x326x228mm
net weigh 2.92kg
NOTE : Specification are subject to change without notice in the course of product improvement.
❏ SPECIFICATIONS
- 1-6 -
- 2-1 -
TAPE DECK ADJUSTMENT
1. AZIMUTH ADJUSTMENT
Figure 1. Azimuth Adjustment Connection Diagram
CH1 CH2
Speaker Out
Playback Mode
Head
Test Tape
MTT-114
L ch
R ch
GND
Dual-trace
synchroscope
Electronic
Voltmeter
L out
R out
Unit
SECTION 2. ELECTRICAL
❏ ADJUSTMENTS
This set has been aligned at the factory and normally will not require further adjustment. As a result, it is not
recommended that any attempt is made to modificate any circuit. If any parts are replaced or if anyone tampers
with the adjustment, realignment may be necessary.
IMPORTANT
1. Check Power-source voltage.
2. Set the function switch to band being aligned.
3. Turn volume control to minimum unless otherwise noted.
4. Connect low side of signal source and output indicator to chassis ground unless otherwise specified.
5. Keep the signal input as low as possible to avoid AGC and AC action.
Deck Mode Test Tape Test Point Adjustment Adjust for
A Deck Playback MTT-114 Speaker Out
DECK Screw
Maximum
Azimuth Screw
B Deck Playback MTT-114 Speaker Out Azimuth Screw Maximum
2. MOTOR SPEED ADJUSTMENT
Figure 2. Motor Speed Adjustment Connection Diagram
Head
Playback Mode
Unit
Speaker Out
GND
L out
R out
Record/Playback
head
Test Tape
MTT-111
Frequency Counter
Deck Mode Test Tape Test Point Adjustment Adjust for Remark
Normal Speed MTT-111 Speaker Out VR201 3kHz ± 1% A Deck
HI-Speed MTT-111 Speaker Out more than 5.4kHz HI-Speed Dubbing Mode
- 2-2 -
3. RECORD BIAS ADJUSTMENT
Head
Unit
PN202
GND
Record/Playback
head
Test Tape
MTT-5511
Record/Playback
and Pause Mode
Frequency Counter
Deck Mode Test Tape Test Point Adjustment Adjust for
Rec/Pause MTT-5511
ERASE HEAD
L203
60kHz±5kHz (Auto stop)
WIRE(PN202) 85kHz±5kHz(Auto Reverse)
Figure 3. Record Bias Adjustment Connection Diagram
- 2-3 -
❏ TROUBLESHOOTING
TURN ON CD
CONNECTOR CHECK ( PN808,PN807 )
CHECK POWER SUPPLY CIRCUIT( PN808 )
CHECK MICOM INTERFACE CIRCUIT( PN807 )
CHECK MICOM INTERFACE CIRCUIT( PN807 )
CONNECTOR CHECK(PN801,PN802)
CHECK PICKUP MOVEMENT
CHECK BA5810FP (IC803)
CHECK MN6627933CG (IC801)
CHECK AN22004 (IC802)
CONNECTOR CHECK (PN808)
CONNECTOR CHECK
( PN808,PN807,PN802,PN801 )
OPEN CLOSE CHECK
“ READING ”
DISPLAY CHECK
READING OK CHECK
IF PLAY, AUDIO
OUTPUT CHECK
OK
NO
NO
NO
NO
YES
YES
YES
YES
YES
• CD PART
- 2-4 -
• OPEN CLOSE NG
CONNECTOR LOCKING CHECK ( PN808,PN807 )
DEFECTIVE MAIN
POEWR SUPPLY
DEFECTIVE MICOM
DEFECTIVE IC803
DEFECTIVE
MECHANISM
CHECK POWER SUPPLY CIRCUIT( PN808 ,PN807)
PN808 PIN 5 = 6.2V, PIN 7 = 5V
PN807 PIN 1 = 5V
CHECK VOLTAGE CHANGE OF OPEN CLOSE ,
AND BTLMUTE VOLTAGE(= 5V)
(PN807 PIN 20:OPEN, 19:CLOSE, 4:BTLMUTE)
CHECK VOLTAGE CHANGE LO+, LO- OF IC803
(PN807, PIN OPEN:20, CLOSE:19)
YES
YES
YES
NO
NO
NO
NO
- 2-5 -
• “ READING ” DISPLAY CHECK
(= ONLY “CD “DISPLAY)
CONNECTOR LOCKING CHECK
(PN808,PN807,PN802,PN801 )
DEFECTIVE CONNECTOR OR
MAIN POWER SUPPLAY
DEFECTIVE IC805
DEFECTIVE MICOM OR
CONNECTOR
DEFECTIVE MICOM OR
CONNECTOR
DEFECTIVE IC801
CHECK VOLTAGE THE PIN 2 OF IC805
IC805 PIN2 : 3.3V
CHECK RESET SIGNAL OF PN807
PN807 PIN12 : 5V
CHECK POWER SUPPLY
PORT( PN808 ,PN807)
PN808 PIN 5 = 6.2V, PIN 7 = 5V
PN807 PIN 1 = 5V
CHECK POWER SUPPLY
PORT( PN808 ,PN807)
PN808 PIN 5 = 6.2V, PIN 7 = 5V
PN807 PIN 1 = 5V
CHECK MICOM INTERFACE
CIRCUIT( PN807 )
PN807 PIN 11,13,14,15 SIGNAL CHECK
(11: STAT, 13: MDATA, 14:MCLK, 15:MLD)
CHECK THE WAVE FORM #1
YES
YES
YES
YES
YES
NO
NO
NO
NO
NO
- 2-6 -
• READING OK CHECK
(= “NO DISC” DISPLAY)
AAAA
BBBB
CCCC
DDDD
EEEE
CONNECTOR LOCKING
CHECK(PN801,PN802)
DOES SLED MOVE ?
CHECK PN802 PIN 3,4( SL+,SL-)
DEFECTIVE PICKUP OR
IC803 OR IC801 OR IC802
DEFECTIVE PICKUP OR
IC803 OR IC801 OR IC802
DEFECTIVE PICKUP OR
IC803 OR IC801
DEFECTIVE PICKUP OR
IC802
DEFECTIVE PICKUP OR
IC803
DEFECTIVE PICKUP OR
IC803 OR IC801 OR IC802
CHECK PN802 PIN 10( LD )
CHECK PN801 PIN 14,15
(TA- ,TA+)
CHECK PN802 PIN
5,6( SP+,SP-)
CHECK PN801 PIN 13,16
( FA-, FA+)
DOES LENSE MOVE ?
(= UP & DOWN)
DOES LASER LIGHT ?
DOES SPINDLE ROTATE ?
IS READING OK ?
YES
YES
YES
YES
YES
NO
NO
NO
NO
NO
- 2-7 -
CHECK PN802 CONNECTOR LINE
DEFECTIVE IC801
DEFECTIVE IC803
DEFECTIVE PN802
CONNECTOR
DEFECTIVE PICKUP
SLED MOTOR
• READING OK CHECK #A
(= “NO DISC” DISPLAY)
AAAA
DOES SL+ WAVEFORM APPEAR AT
( IC803 PIN14 AND PN802 PIN3)
WAVEFORM #2
SLED MOTOR WAVE
DOES SLIN WAVEFORM
APPEAR AT
( IC803 PIN 5)
WAVEFORM #2
SLED DRIVE WAVE
YES
YES
NO
NO
NO
NO
NO
- 2-8 -
CHECK PN801 CONNECTOR LINE
DEFECTIVE IC801
DEFECTIVE IC803
DEFECTIVE PN801
CONNECTOR
DEFECTIVE PICKUP
FOCUS ACTUATOR
• READING OK CHECK #B
(= “NO DISC” DISPLAY)
BBBB
DOES FA+ WAVEFORM APPEAR AT
( IC803 PIN15 AND PN801 PIN16)
WAVEFORM #3
FOCUS COIL DRIVE WAVE
DOES FAIN- WAVEFORM
APPEAR AT
( IC803 PIN 26)
WAVEFORM #3
FOCUS DRIVE WAVE
YES
YES
NO
NO
NO
NO
NO
- 2-9 -
CHECK PN801 CONNECTOR LINE
DEFECTIVE IC805
DEFECTIVE IC802
DEFECTIVE Q801 OR
D811
DEFECTIVE PN801
CONNECTOR
DEFECTIVE PICKUP
LASER PART
• READING OK CHECK #C
(= “NO DISC” DISPLAY)
CCCC
IS ?V APPLIED TO PIN10 OF
PN801
LASER SUPPLY VOLTAGE CHECK
IS 3.3 V APPLIED TO
PIN3 OF IC802
RF IC SUPPLY VOLTAGE
CHECK
IS 2.0 V PIN2 OF IC802
LASER CONTROL
VOLTAGE CHECK
YES
YES
NO
NO
NO
NO
NO
NO
- 2-10 -
CHECK PN802 CONNECTOR LINE
DEFECTIVE IC801
DEFECTIVE IC803
DEFECTIVE PN802
CONNECTOR
DEFECTIVE PICKUP
SPINDLE MOTOR
• READING OK CHECK #D
(= “NO DISC” DISPLAY)
DDDD
DOES SP+ WAVEFORM APPEAR AT
( IC803 PIN12 AND PN802
PIN6)WAVEFORM #4
SPINDLE MOTOR DRIVE WAVE
DOES SPIN WAVEFORM
APPEAR AT( IC803 PIN 6)
WAVEFORM #4
SPINDLE DRIVE WAVE
YES
YES
NO
NO
NO
NO
- 2-11 -
CHECK PN802 CONNECTOR LINE
DOES ARF SIGNAL APPEAR?
(IC802 PORT 8)
WAVEFORM #6
DOES FE, TE SIGNAL APPEAR?
(IC802 PORT FE:23, TE:21)
WAVEFORM #6
DEFECTIVE IC801
DEFECTIVE IC803
DEFECTIVE PN802
CONNECTOR
DEFECTIVE PICKUP OR
IC802
DEFECTIVE PICKUP OR
IC802
DEFECTIVE IC801
• READING OK CHECK # E
(= “NO DISC” DISPLAY)
EEEE
DOES TA+ WAVEFORM APPEAR AT
( IC803 PIN17 AND PN801 PIN15)
WAVEFORM #5
TRACKING COIL DRIVE WAVE
DOES TAIN- WAVEFORM
APPEAR AT
( IC803 PIN 23)
WAVEFORM #5
TRACKING DRIVE WAVE
YES
YES
YES
NO
NO
NO
NO
NO
NO
NO
VKK PART
Does DC - 33V appear at
CN302 Pin .
Check the Voltage of IC301
pin51
Dose -33V appear at
ZD902(-)
Check the Q903
TURN ON
Check the PATTERN
Replace the ZD902
Replace the Q903
Refer to power circuit
END
Check the -33V(LOWER)
of C916
Replace the D704,
D705
YES
YES
NO
NO
P-SENS PART
Does +5V appear at ZD901?
Check the pattern of
IC301 Pin .
Check the waveform
of D913(cathod).
Check the R768 and
replace ZD901.
Replace the D703
YES
YES
NO
NO
26
28
• AUDIO PART
- 2-12 -
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