LG OJ98 Service manual

SERVICE MANUAL

CAUTION

BEFORE SERVICING THE UNIT, READ THE “SAFETY PRECAUTIONS” IN THIS MANUAL.

Internal Use Only

MINI HI-FI SYSTEM

APRIL, 2017P/NO : AFN77912846

MODEL: OJ98

CONTENTS

SECTION 1 ........ GENERAL

SECTION 2 ........ CABINET & MAIN CHASSIS

SECTION 3 ........ ELECTRICAL

SECTION 4 ........ MECHANISM (DM19D)

SECTION 5 ........ REPLACEMENT PARTS LIST

1-1

SECTION 1

SUMMARY

CONTENTS

SERVICING PRECAUTIONS ............................................................................................................................ 1-3

ESD PRECAUTIONS ......................................................................................................................................... 1-5

HIDDEN KEY MODE ......................................................................................................................................... 1-6

1. HIDDEN KEY MODE TABLE .................................................................................................................... 1-6

2. HIDDEN KEY MODE DESCRIPTION ....................................................................................................... 1-7

SERVICE INFORMATION FOR EEPROM ........................................................................................................ 1-9

PROGRAM DOWNLOAD GUIDE .................................................................................................................... 1-10

FOTA UPDATE STEP USING BT APP .......................................................................................................... 1-13

SPECIFICATIONS ........................................................................................................................................... 1-15

1-2

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.

Storage in conductive bag

Drop 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.

NEVER look directly at the laser beam, and don’t allow contact with fingers or other exposed skin.

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 lens.

Pressure

Magnet

How to hold the pick-up

Cotton swab

Conductive Sheet

6) Never attempt to disassemble the pick-up. Spring has 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.

1-3

Pressure

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 or 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 (1 M)

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.

Armband

Resistor (1 M)

Conductive Sheet

1-4

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.

1-5

HIDDEN KEY MODE

1. HIDDEN KEY MODE TABLE

HIDDEN MODE ENTRANCE KEY(Audio) EXIT KEY

Version Check

EEPROM INITIAL

Option EDIT

APD Test Display

Disc Lock On/Off

Power Disc Lock On/Off

Demo ALL Key Lock

BT Auto Power On/Off Front/Remote Control Key ‘Power’ for 5s

ChildSafe On/Off Volume 0(Min) + Front ‘OK’ for 3s Volume 0(Min) + Front ‘OK’ for 3s

Measure

Front ‘Stop’  + Remote Control Key ‘Play’ for 5s

Front ‘Stop’  + Remote Control Key ‘ ‘ for 5s

Front ‘Stop’  + Remote Control Key ‘3’ for 5s

Front ‘Stop’  + Remote Control Key ‘Stop’  for 5s

Front ‘Stop’  + Front ‘Open’ for 5s Front ‘Stop’  + Front ‘Open’ for 5s

Front ‘Stop’  + Remote Control Key ‘9’ for 5s

Front ‘Stop’  + Remote Control Key ‘1’ for 5s

Remote Control Key ‘Play’ for 1.5s

Auto exit

Front ‘Stop’  + Remote Control Key ‘ ‘

Auto exit

Front ‘Stop’  + Remote Control Key ‘Stop’  for 5s

Front ‘Stop’  + Remote Control Key ‘9’ for 5s

Front/Remote Control Key ‘Power’ SET Power Off

Remote Control Key ‘SOUND EFFECT’

1-6

2. HIDDEN KEY MODE DESCRIPTION

2-1. Version Check

- Function : Version Check.

- Entrance Key : Front ‘Stop’ + Remote Control Key ‘Play’ for 5s.

- Exit Key : Remote Control Key ‘Play’ for 1.5s.

- Operation explanation : Remote Control Key OR .

VFD Display (Example) Result

MCS Version

MICOM Version

OPTION Version

DEMO Version

DJ PRO Version

EQ Version

EQ Check sum Version

2-2. EEPROM Initial

- Function : Initialize data stored in EEPROM and BACKUP RAM data.

- Entrance Key : Front ‘Stop’ + Remote Control Key ‘ ‘ for 5s.

- Exit Key : Auto exit.

- Explanation : ‘E2P CLR’ is displayed on the VPD and turn off the power automatically.

2-3. OPTION EDIT (EEPROM)

- Refer to the page 00.

2-4. APD Test Display

- Function : Auto Power Down timer is displayed on VFD.

- Entrance Key : Front ‘Stop’ + Remote Control Key ‘3’ for 5s.

- Exit Key : Auto Exit.

- Explanation : display APD Timer HH=(hour) MM=(min), SS=(sec).

1-7

2-5. Disc Lock On/Off

- Function : Lock Open Key.

- Entrance Key : Front ‘Stop’ + Remote Control Key ‘Stop’ for 5s.

- Exit Key : Front ‘Stop’ + Remote Control Key ‘Stop’ for 5s.

- Operation Explain : Open Key Block ‘LOCKED’.

2-6. Power Disc Lock On/Off

- Function : Lock Power / Open / Front Volume Key.

- Entrance Key : Front ‘Stop’ + Front ‘Open’ for 5s.

- Exit Key : Front ‘Stop’ + Front ‘Open’ for 5s.

2-7. Demo All Key Lock

- Function : All key is blocked on Demo Mode.

- Entrance Key : Front ‘Stop’ + Remote Control Key ‘9’ for 5s.

- Exit Key : Front ‘Stop’ + Remote Control Key ‘9’ for 5s.

- Operation Key : In demo mode, all key blocks. (only the volume key is effective when All Key Lock is enabled.) To release Demo Mode, it is available after All Key Lock Off.

2-8. BT Auto Power On/Off

- Function : Ability to disable BT Auto Power On function by network shutdown regulation.

- Entrance Key : Front/Remote Control Key ‘Power’ for 5s.

- Exit Key : SET Power Off with Front / Remote Control Key ‘Power’.

2-9. ChildSafe On/Off

- Function : Power off Fade-in to previous volume.

- Entrance Key : Volume 0(Min) + Front ‘OK’ for 3s.

- Exit Key : Volume 0(Min) + Front ‘OK’ for 3s.

2-10. Measure

- Function : Change to EQ for Measure mode, Down algorithm operation Disable, Change to output setting value for measure mode.

- Entrance Key : Front ‘Stop’ + Remote Control Key ‘1’ for 5s

- Exit Key : Remote Control Key ‘SOUND EFFECT’

1-8

SERVICE INFORMATION FOR EEPROM

POWER ON

VFD “NO DISC” status

It is possible at any function. (ex. It is possible at VFD “NO USB” status, too.) This is an example.

Front ‘Stop’ + Remote control ‘ ’

push same timing during 5 s

FLD “OP00-…..”

Move to appropriate position

And make changes with remote control

“ , , REPEAT, ” key.

Press ‘PLAY ( )’ Key

VFD “WRITE OK”

DETECT NEW EEPROM (OPTION EDIT SCREEN)

NAME

OPT0 OPT1 OPT2 OPT3 OPT4 OPT5 OPT6 OPT7 OPT8 OPT9 OPT10 OPT11 OPT12 OPT13 OPT14

HEX

01 31

26 05 00

00 4F 4A

Front ‘Stop’ + Remote control ‘ ’

push same timing during 5 s

VFD “E2P CLR”

Completed

1-9

PROGRAM DOWNLOAD GUIDE

1. AUDIO PROGRAM

Download program file name must be MICOM_OJ98_YYMMDDX.HEX

If security program(Water Wall) is activated on PC, you must save the file to the USB storage device and disable the security software, then download the file to your set. Downloading file proceeds in the same way at USB1 function and USB2 function.

Caution:

When downloading the file, you should neither unplug the USB device, change to the other function, nor power off the device. USB device must be unplugged when the downloading process is completed.

ON VFD DISPLAY SCREEN

NO USB

Insert USB device at USB function.



MICOM UP



FINISH



AUTO POWER OFF

1) (Fast) Format USB device.

2) Copy Firmware file to USB device.

1-10

2. CD PROGRAM

Download program file name must be HG790_OJ98_YYMMDDX.bin

Caution:

When downloading the file, you should neither unplug the USB device, change to the other function, nor power off the device. USB device must be unplugged when the downloading process is completed.

ON VFD DISPLAY SCREEN

NO USB

Insert USB device at USB function.



FIRMWARE



FINISH



AUTO POWER OFF

1) (Fast) Format USB device.

2) Copy Firmware file to USB device.

1-11

3. EQ & DEMO PROGRAM

Download program file name must be EQ_DEMO_PRG_OJ98_XXXX.BIN

Caution:

When downloading the file, you should neither unplug the USB device, change to the other function, nor power off the device. USB device must be unplugged when the downloading process is completed.

ON VFD DISPLAY SCREEN

NO USB

Insert USB device at USB function.



EQDEMOUP



FINISH



AUTO POWER OFF

1) (Fast) Format USB device.

2) Copy Firmware file to USB device.

1-12

FOTA UPDATE STEP USING BT APP

Step1 : App connecting

(Check FW version)

After connecting the BT App with SET, the user could ﬁ nd the “Device Version info” on Setting tab.

Step2 : Device version info

When touch the “Device Version info” button, user could ﬁ nd the current and latest SET version on pop-up menu.

Step3 : Select update button

When touch the “Update” button, user could update the SET ﬁ rmware using FOTA.

Step4 : Conﬁ rm update

Select the OK button on the caution message.

1-13

Step5 : Download from CDN server

Step6 : Transfer FW

1st step is download from CDN server to smart phone. The progress bar is displayed on BT App.

After completed the download from server, smart phone start to transfer the ﬁ rmware to the SET. The progress bar is displayed on BT App.

Step7 : FW Flash Writing Step8 : FOTA complete

After completed the download from the smart phone, the SET overwrite the ﬁ rmware to ﬂ ash memory.

When ﬁ nishing the ﬂ ash memory writing, pop-up message about ﬁ nish is displayed and the SET auto power off.

1-14

SPECIFICATIONS

 GENERAL

Power requirements Refer to the main label on the unit. Power consumption Refer to the main label on the unit. Networked standby : 0.5 W (If all network ports are activated.) Dimensions (W x H x D) Approx. 380 mm x 1095 mm x 375 mm Operating temperature 5 °C to 35 °C (41 °F to 95 °F) Operating humidity 60 %

 INPUTS / OUTPUTS

Analog audio in (AUX IN) 2.0 Vrms (1 kHz, 0 dB), 600 Ω, RCA jack (L, R) Analog audio out (AUX OUT) 2.0 Vrms (1 kHz, 0 dB), 600 Ω, RCA jack (L, R) Portable in (PORT. IN) 1.0 Vrms (3.5 mm stereo jack) x 1 Microphone (MIC 1/2) Sensitivity 20 mV (1 kHz), 6.3 mm jack x 2

 TUNER

FM Tuning Range 87.5 to 108.0 MHz or 87.50 to 108.00 MHz

 SYSTEM

Frequency Response 40 to 20,000 Hz Signal-to-noise ratio More than 75 dB Dynamic range More than 80 dB Bus Power Supply (USB) 5 V 500 mA

 AMPLIFIER (RMS Output power)

Total output 1,800 W RMS HIGH 450W RMS × 2 (6Ω at 1 kHz, 15% THD) LOW 450W RMS × 2 (6Ω at 200 Hz, 15% THD)

 Design and specifications are subject to change without notice.

1-15

1-16

SECTION 2

CABINET & MAIN CHASSIS

CONTENTS

EXPLODED VIEWS ........................................................................................................................................... 2-3

1. CABINET AND MAIN FRAME SECTION ................................................................................................. 2-3

2. DECK MECHANISM SECTION ................................................................................................................ 2-5

3. PACKING ACCESSORY SECTION ......................................................................................................... 2-7

DISASSEMBLY INSTRUCTIONS ..................................................................................................................... 2-8

2-1

2-2

RMC

TOP

A51

475

476

475

270

269

521

475

521

272

CABLE3

MAIN

SMPS

464

254

CABLE2

255

464

256

258

259

464

256

475

A44

475

257

262

261

475

A46

475

265

476

264

A60

475

263

271

475

273

274

464

255

476

475

464

250

464

277

464

253

251

260L

260R

475

A41

CABLE4

CABLE5

475

A47

CABLE1

475

A50

EXPLODED VIEWS

1. CABINET AND MAIN FRAME SECTION

2-42-3

NOTES) THE EXCLAMATION POINT WITHIN AN

EQUILATERAL TRIANGLE IS INTENDED TO ALERT THE SERVICE PERSONNEL TO THE PRESENCE OF IMPORTANT SAFETY INFORMATION IN SERVICE LITERATURE.

2. DECK MECHANISM SECTION (DM19D)

2-62-5

1439

A001

1005

1001

1049

1437

1024

1003

1011

1437

1004

1026

1016

1013

1015

1020

1012

A006

1018

1019

1030

A005

1045

1043

1439

1002

3. PACKING ACCESSORY SECTION

801 Owner’s manual

808 Batteries

826 Filter, Ferrite Core

900 Remote Control

803 Packing

825 FM Wire Antenna

300 Power Cord

802 Box

804 Bag

803 Packing

2-7

1) Remove the 6 screws.

DISASSEMBLY INSTRUCTIONS

Figure 1. Panel Side L/R disassembly - 1

2) Remove the 4 screws on the left and right sides, and pull Cover Side Ass’y L / R backward.

Figure 2. Panel Side L/R disassembly - 2

2-8

3) Remove the 3 screws.

Figure 3. Panel Top disassembly - 1

4) Remove the 2 screws on the left and right, and remove the top panel.

Figure 4. Panel Top disassembly - 2

2-9

5) Remove 7 screws, and remove Panel Rear.

6) Remove the 4 screws.

Figure 5. Panel Rear disassembly

Figure 6. Main Set disassembly - 1

2-10

7) Remove the 5 screws.

Figure 7. Main Set disassembly - 2

8) Remove the sparkling LED connector, speaker connector and power cables. And lift it upwards.

Figure 8. Main Set disassembly - 3

2-11

9) Complete removal of the Main Set.

Figure 9. After detaching the Main Set

2-12

+ 62 hidden pages

LG OJ98 Service manual

Specifications and Main Features

Frequently Asked Questions

User Manual