LG FFH-8900 Service manual
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.
SERVICING PRECAUTIONS
- 3 -
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
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 object(such as driver), simply press the RESET button 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.
NOTES REGARDING COMPACT DISC PLAYER REPAIRS
- 4 -
Armband
Conductive
Sheet
Resistor
(1 Mohm)
Resistor
(1 Mohm)
VOLUME
VOLUME KNOB
DOWN
RESET button
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).
ESD PRECAUTIONS
- 5 -
SPECIFICATIONS
1. AMP SECTION
① Power Output (6 Ω, 2 channel, T.H.D. 10%)
....................................................................
100W+100W
② T.H.D
...........................................................................................................................................
0.15%
③ Frequency Response (-3dB down)
...................................................................................
30Hz~20kHz
④ Signal-to-noise Ratio
....................................................................................................................
81dB
⑤ Input Sensitivity AUX
...........................................................................................................
300±50mV
⑥ Channel Difference 1kHz
................................................................................................................ 2dB
2. TUNER SECTION
1) FM/OIRT
① Frequency Range.................................................................................................... 87.5MHz~108MHz
................................................................................................or 65.0MHz~74.0MHz & 87.5MHz~108MHz
② Intermediate Frequency.......................................................................................................... 10.7MHz
③ Sensitivity (69MHz/70MHz/71MHz/90.1MHz/98.1MHz/106.1MHz).............................................. 14dB
④ Signal-to-noise Ratio 98.1MHz(Mono/Stereo)..................................................................... 63dB/58dB
⑤ Image Rejection 106.1MHz .......................................................................................................... 38dB
⑥ IF Rejection 90MHz...................................................................................................................... 85dB
⑦ Distortion 98MHz(Mono/Stereo).......................................................................................... 0.7%/1.2%
⑧ Frequency Response (-3dB)............................................................................................ 60Hz~14kHz
⑨ Stereo Separation (100Hz/1kHz/10kHz).................................................................... 28dB/28dB/23dB
2) AM(MW)
① Frequency Range.................................... 522kHz~1,611kHz,530kHz~1,720kHz or 530kHz~1,610kHz
② Intermediate Frequency............................................................................................................ 450kHz
③ Usable Sensitivity ......................................................................................................................... 56dB
④ Image Rejection 1404kHz............................................................................................................. 25dB
⑤ IF Rejection 603kHz ..................................................................................................................... 45dB
⑥ Selectivity 1008kHz ...................................................................................................................... 38dB
⑦ Signal-to-noise Ratio 1008kHz..................................................................................................... 37dB
⑧ Distortion 1008kHz........................................................................................................................ 1.6%
⑨ Frequency Response (-6dB)........................................................................................ 100Hz~2000Hz
3) SW(OPTIONAL)
① Frequency Range......................................................................................................... 5.8MHz~18MHz
② Intermediate Frequency............................................................................................................ 450kHz
③ Usable Sensitivity ......................................................................................................................... 40dB
④ Signal-to-Noise Ratio.................................................................................................................... 37dB
⑤ Distortion ......................................................................................................................................... 2%
4) LW(OPTIONAL)
① Frequency Range........................................................................................................ 153kHz~281kHz
② Intermediate Frequency............................................................................................................ 450kHz
③ Usable Sensitivity ......................................................................................................................... 62dB
④ Signal-To-Noise Ratio (200kHz)................................................................................................... 30dB
⑤ Distortion (200kHz) ......................................................................................................................... 3%
- 6 -
3. TAPE DECK SECTION
① Tape Speed (MTT-111) / Normal Speed............................................................................... 3kHz±1.5%
② Wow Flutter (MTT-111) .................................................................................................................. 0.25%
③ Fast Forward and Rewind Time (C-60)......................................................................................... 130sec
④ Frequency Response (6dB range) ....................................................................................... 125Hz~8kHz
⑤ Signal-to-noise Ratio (Playback/Record) ................................................................................ 48dB/43dB
⑥ Distortion (Playback/Record).................................................................................................... 2% / 3.5%
⑦ Crosstalk (Playback: 1kHz)..................................................................................................... 55dB/53dB
⑧ Channel Separation (Playback: 1kHz) .................................................................................... 50dB/43dB
⑨ Erase Ratio....................................................................................................................................... 55dB
4. COMPACT DISC PLAYER SECTION
① Frequency Response (40Hz-18kHz)...................................................................................... +0.5/-3.5dB
② Signal-to-noise Ratio (1kHz)............................................................................................................. 73dB
③ Dynamic Range (1kHz)..................................................................................................................... 70dB
④ T.H.D. (1kHz).................................................................................................................................... 0.4%
⑤ Separation (100Hz/1kHz/10kHz) ................................................................................... 42dB/48dB/40dB
⑥ Access Time Short / Long......................................................................................................... 2sec/5sec
5. GENERAL
① Power requirement.................................................................................... Refer to the back panel of unit
② Power consumption......................................................................................................................... 410W
③ Dimension (W x H x D)........................................................................................... 360 x 362 x 374 (mm)
④ Weight (net).................................................................................................................................... 10.0kg
NOTE : Specification are subject to change without notice in the course of product improvement.
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- 17 -
BLOCK DIAGRAM
FFH-8900A/S.JA5SSSR_A3 1996.2.7 11:7 AM 페이지17
- 8 -
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
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.
ADJUSTMENTS
Deck Mode Test Tape Test Point Adjustment Adjust for
A Deck Playback MTT-114 Speaker Out DECK Screw Maximum
B Deck Playback MTT-114 Speaker Out Azimuth Screw Maximum
2. MOTOR SPEED ADJUSTMENT
Figure 1. Azimuth Adjustment Connection Diagram
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%
Hi-Speed MTT-111 Speaker Out more than 5.4kHz High-Speed Dubbing Mode
TAPE DECK ADJUSTMENT
1. AZIMUTH ADJUSTMENT
- 9 -
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 Wire(PN202) L203 90kHz±5kHz
Figure 3. Record Bias Adjustment Connection Diagram
Figure 4. Tuner(S curve) Adjustment Connection Diagram
4. TUNER ADJUSTMENT
Unit
Signal Generator
GND
Electronic
OSCILLOSCOPE
FM Antenna
Terminal
Speake
Item Test Point Adjustment Adjust for
DC Voltage Checker Pin TP1, TP2 L106 0V±50mV
- 38 -
EXPLODED VIEW/PARTS LIST
••
CABINET
FFH-8900A/S.JA5SSSR_A3 1996.2.7 11:8 AM 페이지38
- 40 -
400
011
503
401
401
009
010
501
502
507
508
013
406
409
410
036
032
038
034
035
039
029
040
031
028
027
026
014
015
403
504
024
025
023
405
A01
402
022
016
017
018
019
020
021
505
007
008
003
004
005
001
002
404
400
400
506
037
006
••
TAPE DECK MECHANISM: AUTO REVERSE DECK
LOCA.NO. PART NO. SPECOFOCATION
A01 6768R-UP01A 50-093-4249 PCB AS
001 6768R-BP01B 02-084-4202 BELT/FELT
002 6768R-BP01A 02-084-4204 BELT/FELT
003 6768R-AP01D 50-239-4027 CWL44
004 6768R-AP01E 50-239-4026 ARM
005 6768R-SP01E 01-082-4645 SPRING
006 6768R-QP01A 50-093-4316 MOTOR
007 6768R-GP01A 50-093-4603 GEAR
008 6768R-SP01F 01-082-4598 SPRING
009 6768R-MP01C 50-219-4014 MOLD
010 6768R-SP01C 01-082-4652 SPRING
011 6768R-SP01A 01-081-4601 SPRING
013 6768R-SP01B 01-082-4651 SPRING
014 6768R-SP01G 0-082-4597 SPRING
015 6768R-AP01A 50-268-3016 ARM
016 6768R-GP01C 50-093-4069 GEAR
017 6789R-AP01C 50-239-4072 ARM
018 6768R-GP01D 50-222-4007 GEAR
019 6768R-SP01H 01-081-4657 SPRING
020 6768R-BP01C 02-083-4188 BELT/FELT
021 6768R-LP01A 50-223-4254 PULLEY
022 6768R-VP01A 50-093-4125 SOLENOID
023 6768R-GP01B 50-221-3009 GEAR
024 6768R-AP01B 50-139-4292 ARM
025 6768R-JP01B 50-093-3361 PULLEY
026 6768R-SP01D 01-080-4609 SPRING
027 6768R-DP01A 50-259-3342 LEVER
028 6768R-RP01A 22-027-41054 ROLLER
029 6768R-MP01A 50-219-4033 MOLD
031 6768R-SP01L 01-080-4649 SPRING
032 6768R-EP01A 50-093-4070 HEAD AY
033 6768R-JP01A 50-093-3360 PULLEY
034 6768R-SP01K 01-082-4650 SPRING
035 6768R-PP01A 50-119-4046 PRESS
036 6768R-PP01B 50-160-4108 PRESS
037 6768R-JP01C 50-093-3315 PULLEY
038 6768R-MP01D 50-219-4034 MOLD
040 6768R-SP01M 01-080-4607 SPRING
400 6768R-CP01A GRE10A2003 SCREW
401 6768R-CP01B GRE20A2005 SCREW
402 6768R-CP01C GSE10A1704 SCREW
403 6768R-CP01D GSL10A2004 SCREW
404 6768R-CP01E GSP10A2603 SCREW
405 6768R-CP01F GSP11A2012 SCREW
406 6768R-CP01G GSE20A2004 SCREW
409 6768R-CP01L GSD10A2018 SCREW
410 6768R-CP01M 03-300-4056 SCREW
501 6768R-WP01A GWM19S035035 WASHER
502 6768R-WP01B GWM17S0500035S WASHER
503 6768R-WP01C GWM40X075010 WASHER
504 6768R-WP01D GWP21X045020 WASHER
505 6768R-WP01E GWM12X030040S WASHER
506 6768R-WP01H GWM23X040020 WASHER
507 6768R-WP01F GWM21X040040 WASHER
508 6768R-WP01G GWM19X055035S WASHER
FFH-8900A/S.JA5SSSR_A3 1996.2.7 11:8 AM 페이지40
- 41 -
••
CD MECHANISM
416
101
102
105
134
135
134
A35
421
A30
421
118
417
417
103
109
A26
119
104
108
107
106
418
416
419
115
112
116
420
117
127
126
114
113
125
120
121
124
416
123
122
417
A30 3040SB0004A BASE PU ASSY(CDM-H1303)
A35 4405SCB001A MECHANISM ASSY KSM-213CCM SONY HI-FI FRONT LO
101 3390SB0002A TRAY DISC(CDM-H1303)
102 4470SB0011A GEAR TRAY B(CDM-H1303)
103 4470SB0010A GEAR TRAY A(CDM-H1303)
104 4400SB0001B BELT TRAY(CDM-H1303)
105 4680SBP002A MOTOR(MECH) ASSY TRAY
106 6871SF21RAD PWB(PCB)ASSY 3CH M/D SENSOR PWB ASSY
107 4794SB0003A GUIDE WCRM(CDM-1303)
108 4371SB0002A SHAFT ASSY TRAY(CDM-H1303)
109 3390SB0001A TRAY LOADING(CDM-H1303)
112 4400SB0001A BELT MAIN(CDM-H1303)
113 4470SB0003A GEAR PULLEY(CDM-H1303)
114 4470SB0004A GERA LOADING(CDM-H1303)
115 6871SB21RAD PWB(PCB)ASSY 3CH M/D U/D/O/C PWB ASSY
116 4470SB0006A GEAR PU DOWN(CDM-H1303)
117 4470SB0008A GEAR PU UP-B(CDM-H1303)
118 4471SB0001A GEAR ASSY GEAR CAM ASSY
119 4860SB0002A CLAMP CLAMP ASSY
120 4974SB0001A GUIDE CAM(CDM-H1303)
121 4970SBN002A SPRING CAM(CDM-H1303)
122 3040SB0002A BASE MAIN(CDM-H1303)
123 6871SD21RAD PWB(PCB)ASSY 3CH M/D CAM PWB ASSY
124 6871SC21RAD PWB(PCB)ASSY 3CH M/D OPEN PWB ASSY
125 4680SBP001A MOTOR(MECH) PULLEY ASSY(CDM-H1303)
126 4470SB0007A GEAR PU UP-A(CDM-H1303)
127 4470SB0005A GEAR MAIN(CDM-H1303)
134 4900SB0001A DAMPER DAMPER RUBBER
135 3040SB0003A BASE PU(CDM-H1303)
416 88H-0004 CD MECHA PARTS 3X12X12FNM
417 88H-0002 CD MECHA PARTS 3X9X12FZMY
418 353-025BAAA SCREW D3.0 L8.0 MSWR3/(BK)
419 88H-0003 CD MECHA PARTS 3X12X10FZMY
420 353S353F SCREW D2.6 L4.0 MSWR3/(BK)
421 6756SBX001A
CD MECHANISM PARTS SCREW 2.6X10X10XFZMY CDM-H813
REF.NO. PART NO. DESCRIPTION SPECOFOCATION
FFH-8900A/S.JA5SSSR_A3 1996.2.7 11:8 AM 페이지41
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