SECTION 1. GENERAL ❏ SERVICING PRECAUTIONS I 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.
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I 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.
❏ ESD PRECAUTIONS I 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 integrat- ed 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.
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Signal to Noise Ratio 30 dB Frequency Response 140 - 1800 Hz [AMP]MPLIFIER(LH-W96’s) Output Power 100W +100W+150W [LM-U1560+LMS-U1560W(SUB WOOFER)] 100W+100W [LM-U1060] 50W +50W [LM-U560] 30W + 30W [LM-U360] T.H.D 0.5% Frequency Response 40 - 20000 Hz Signal-to-noise ratio 75 dB [TAPE] Tape Speed 4.75cm/sec...
SECTION 2. ELECTRICAL ❏ ELECTRICAL TROUBLESHOOTING GUIDE(AUDIO PART) I MICOM PART CHECK I Refer to SMPS P7904 6PIN P-SENS check Troubleshooting IC101 KIA7042? Check if IC101 KIA7042 input is over 5V IC101 KIA7042 relevant parts check Check if IC101 KIA7042 IC100 78KO/KF2 1 PIN input is over 4.3V Power Check...
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I MICOM PART CHECK II P7904 5PIN 5.6V check Refer to SMPS Troubleshooting D101 1SR35 both terminal power check Output 5V operation check D101 1SR35 relevant parts relevant parts check replacement Q101 EMITTER 5V check and COLLECTO normal Q102 BASE PIN 0.6V HIGH check Check if IC101 KIA7042 output...
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I IC103 KS4CD21CS CHECK IC100 78KOKF2 22,24 PIN Check Refer to MICOM 22 PIN DATA MICOM power 5V check Troubleshooting relevant parts check relevant parts replacement normal normal I FLD DISPLAY CHECK P7904 1,2,3 power check Refer to SMPS Troubleshooting F1+, F2 both terminal: 5V and above VKK: power is over 26V P7302 connection status...
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I TAPE REC PART CHECK IC604 PS9829 #49,#52 PWM Refer to PWM modulation output check part Q601 Collector waveform check P7207 #2.#4 output check Board to Board cantact check P2707 #5.#7 input check IC203 MC4580 #1,#7 check IC203 8 PIN +12V check Refer to SMPS IC201 7.24 PIN REC input Troubleshooting...
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I SMPS POWER CIRCUIT *MAIN PART Check the fuse F901 Replace the fuse Check the DC V of C905. Check BD901, LF901,902 If DC V is over 400V Chcek the DC V Of C909, Check IC901 ,902 Replace IC 901,902 C903,C921 If DC V is in 14~19V and it is steady.
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*P-SENS PART (OPTIONAL PART) Check the PIN6 OF P9702 Check power circuit Trouble If DC V is over 5.6V shooting *VKK PART Check the PIN3 OF P9702 Check power circuit If DC V is over -28V ±2 Trouble shooting - 2-12 -...
❏ ELECTRICAL TROUBLESHOOTIHG GUIDE & WAVEFORM(CD PART) I POWER CHECK GUIDE POWER ON POWER ON PUSH KARAOKE CD BUTTON DOES CD DOES AUX,FM 87.5 APPEAR AT FLD? APPEAR AT FLD? DOES IT DOES DISK1 APPEAR CD APPEAR AT FLD? ERROR AT FLD? CHECK DOES NO DISC OR CONNECTOR (P4703,P4004,...
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I CD PART TURN ON CD CONNECTOR CHECK OPEN CLOSE CHECK ( PN803, PN804 ) CHECK Voltage CN806 PIN1:12, PIN2:6.3V CHECH Vtg PN805 PIN22 : CLOSE,PIN23:OPEN “ READING ” CONNECTOR CHECK (PN802, DISPLAY CHECK PN803, PN804, CN806,PN814 ) CHECK MICOM INTERFACE CIRCUIT( PN805 ) (CE,BTL-MUTE,CD-IN,CDOUT,CLK,WRQ,FSEQ) CONNECTOR READING OK CHECK...
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I OPEN CLOSE NG CONNECTOR LOCKING CHECK ( PN803, PN804, PN814 ) CHECK POWER SUPPLY CIRCUIT ( PN805, CN806) DEFECTIVE MAIN POEWR SUPPLY CN806 PIN1:12V, PIN2:6.3V, PN805 PIN8:+5V_AD CHECK VOLTAGE CHANGE OF OPEN CLOSE IC803 INPUT VOLTAGE DEFECTIVE MICOM PIN6:12V, PIN7:6.3V (PN805 PIN2:BTL_MUTE, 23:OPEN, 22:CLOSE) CHECK VOLTAGE CHANGE LO+, LO- OF DEFECTIVE IC803 IC803 (PN805 PIN23:OPEN, PIN22:CLOSE)
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I “ READING ” DISPLAY CHECK (= ONLY “CD” DISPLAY) CONNECTOR LOCKING CHECK (PN802, PN803,PN804,PN805,CN806 ) CHECK POWER SUPPLY PORT( PN805, DEFECTIVE CONNECTOR OR CN806) CN806 PIN1: 12V, PIN2: 6.3V, MAIN POWER SUPPLAY PIN4: 5V PN805 PIN8 = 5V_AD CHECK VOLTAGE THE PIN 2 OF IC804 DEFECTIVE IC804 IC804 PIN2 : 3.3V CHECK RESET SIGNAL OF PN805...
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I READING OK CHECK (= “NO DISC” DISPLAY) CONNECTOR LOCKING CHECK(PN801,PN802) CHECK PN802 DEFECTIVE PICKUP OR DOES SLED MOVE ? PIN 3,4( SL+,SL-) IC802 OR IC801 DOES LENSE MOVE ? CHECK PN801 DEFECTIVE PICKUP OR (= UP & DOWN) PIN 13,16 ( FA+,FA-) IC802 OR IC801 DEFECTIVE PICKUP OR DOES LASER LIGHT ?
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I READING OK CHECK #A (= “NO DISC” DISPLAY) DOES SL+ WAVEFORM DOES SLIN WAVEFORM DEFECTIVE IC801 APPEAR AT ( IC802 PIN13 APPEAR AT ( IC802 PIN5) AND PN 802 PIN3) WAVE- WAVEFORM #2 SLED FORM #2 SLED MOTOR DRIVE WAVE WAVE DEFECTIVE IC802 CHECK PN802...
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I READING OK CHECK #B (= “NO DISC” DISPLAY) DOES FA+ WAVEFORM DOES FAINWAVEFORM DEFECTIVE IC801 APPEAR AT ( IC802 PIN16 APPEAR AT ( IC802 PIN 25) AND PN801 PIN13) WAVE- WAVEFORM #3 FOCUS FORM #3 FOCUS COIL DRIVE WAVE DRIVE WAVE DEFECTIVE IC802 CHECK PN801...
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I READING OK CHECK #C (= “NO DISC” DISPLAY) IS 3.3 V APPLIED TO PIN30, IS ?V APPLIED TO PIN10 OF DEFECTIVE IC804 36, 39, 41, 61, 68, 75 OF PN801 IC801 LASER SUPPLY VOLTAGE RF IC SUPPLY VOLTAGE CHECK CHECK IS 2.3 V PIN18(LDO) OF DEFECTIVE IC801...
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I READING OK CHECK #D (= “NO DISC” DISPLAY) DOES SP+ WAVEFORM DOES SPIN WAVEFORM DEFECTIVE IC801 APPEAR AT ( IC802 PIN11 APPEAR AT (IC802 PIN6) AND PN802 PIN 5) WAVE- WAVEFORM #4 FORM #4 SPINDLE MOTOR SPINDLE DRIVE WAVE DRIVE WAVE DEFECTIVE IC802 CHECK PN802...
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I READING OK CHECK #E (= “NO DISC” DISPLAY) DOES TA+ WAVEFORM DOES TAINWAVEFORM DEFECTIVE IC801 APPEAR AT ( IC802 PIN17 APPEAR AT ( IC802 PIN 22) AND PN801 PIN14) WAVEFORM #5 TRACKING WAVEFORM #5 TRACKING DRIVE WAVE COIL DRIVE WAVE DEFECTIVE IC802 CHECK PN802 DEFECTIVE PN802...
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I USB PART TURN ON USB CONNECTOR CHECK “ CHECKING ” OR “USB” DISPLAY CHECK ( PN805, CN806, PN810 ) CHECK POWER SUPPLY CIRCUIT( CN806 ) CHECK MICOM INTERFACE CIRCUIT( PN805 ) PIN13: RX (IC805 PIN49 :TXD) PIN14: TX (IC805 PIN33 : RXD) READING OK CHECK CHECK PN810 1 PIN : 5V CHECK PN810 PIN 2(D-), 3(D+)
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I WAVEFORMS OF MAKOR CHECK POINT #1. MICOM INTERFACE WAVEFORM #2. MICOM INTERFACE WAVEFORM (PN805 PIN 26, 19, 3, 15) DURING POWER ON (PN805 PIN 26, 19, 3, 15) DURING NORMAL PLAY PIN 26 : WRQ PIN 26 : WRQ PIN 19 : RESET PIN 19 : RESET PIN 3 : DI (IC801 PIN46 DATA OUT)
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I WAVEFORMS OF MAKOR CHECK POINT #2. SLED DRIVE AND MOTOR WAVEFORM #2. MICOM INTERFACE WAVEFORM (IC802 PIN 5, 13) WHEN FOCUS SEARCH (PN805 PIN 26, 19, 3, 15) DURING NORMAL PLAY PIN 26 : WRQ PIN 5 : SLIN PIN 5 : SLIN PIN 13 : SL+ PIN 13 : SL+...
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I WAVEFORMS OF MAKOR CHECK POINT #4. SPINDLE DRIVE AND MOTOR WAVEFORM #5. TRACK DRIVE AND MOTOR WAVEFORM (IC802 PIN 6, 11) WHEN TOC READING (IC802 PIN 22 , IC802 PIN 17) DURING NORMAL PLAY PIN 22 : TAO PIN 6 : SPIN PIN 17 : TA+ PIN 11 : SP+ #6.
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2. Voltages are DC-measured with a digital voltmeter MODIFIED OR ALTERED WITHOUT PERMISSION IMPLEMENTATION OF THE LATEST SAFETY AND during Play mode. FROM THE LG ELECTRONICS CORPORATION. ALL PERFORMANCE IMPROVEMENT CHANGES INTO • SMPS SCHEMATIC DIAGRAM COMPONENTS SHOULD BE REPLACED ONLY WITH...
❏ TAPE DECK MECHANISM (A/R & A/S : LEFT A/S DECK) LOCA. NO. LG PART NO. DESCRIPTION SPECIFICATION 6720AG0013A Audio Deck CWN42FR605 TOKYO PIGEON L-DOUB 6768RZUP01A Deck Mechanism Parts 50-093-4XXXX PIGEON UNIT PCB A 6768R-EP05A Deck Mechanism Parts 50-093-41234 PIGEON HEAD ASSY...
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❏ TAPE DECK MECHANISM (A/R & A/S : RIGHT A/R DECK) LOCA. NO. LG PART NO. DESCRIPTION SPECIFICATION 6720AG0013A Audio Deck CWN42FR605 TOKYO PIGEON L-DOUB 6768RZHP02A Deck Mechanism Parts ASSY B-DECK PIGEON HEAD 6768R-PP03A Deck Mechanism Parts 33-160-4309 PIGEON PRESS CASSE...