LG-LPCBM340-pr-sm 电路图维修手册.pdf

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1、- 1-1 - CONTENTS SECTION 1. GENERAL SPECIFICATIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-2 SECTION 2. ELECTRICAL ADJUSTMENTS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

2、 . . . . . . 2-1 TROUBLESHOOTING GUDIE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-2 IC VOLTAGE SHEET . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-17 BLOCK DIAGRAM . . . . . . . . . . . . .

3、 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-21 SCHEMATIC DIAGRAM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-23 PRINTED CIRCUIT DIARGAMS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

4、. . . . . . . . . . . . . 2-31 WIRING DIAGRAM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-43 SECTION 3. EXPLODED VIEWS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-1 SECTION 4. REPLACEMENT PARTS LIST . . . .

5、 . . . . . . . . . . . . . . . . . . . . . . . 4-1 RadioFans.CN 收音机爱好者资料库 - 1-2 - SECTION 1. GENERAL SPECIFICATIONS MODELLPC-LM340A/X, LPC-BM340A/X SECTIONLPC-LM345A/X, LPC-BM345A/X Power supplyRefer to the back panel of the unit. Power consumption13W Mass3.24kg External dimensions (W x H x D)360 x

6、 170 x 260mm Output Power 2.5W x 2 Speakers8 x 2 Battery OperationDC 12V, eight “C”(R14) and four “AA”(R6) batteries (not supplied) Fequency response100 18000Hz Signal-to-noise ratio59dB T.H.D0.7% Tuning Range 6574MHz, 87.5108MHz or 87.5 108MHz Intermediate Frequency 10.7MHz AntennaTelescopic antenn

7、a Tuning Range5221611kHz or 530 1610kHz Intermediate Frequency450kHz AntennaFerrite bar antenna Recording System4 Tracks 2 channel stereo Frequency Response125 8000Hz Signal to Noise Ratio40/45dB (REC/PLAY) GeneralCDTAPE TUNER AM (MW)FM * Designs and specifications are subject to change without noti

8、ce. Remote Control Operation Range Point the remote control at the remote sensor and press the buttons. Distance: About 23 ft (7 m)from the front of the remote sensor. Angle: About 30 in each direction of the front of the remote sensor. RadioFans.CN 收音机爱好者资料库 - 2-1 - SECTION 2. ELECTRICAL ADJUSTMEN

9、TS 1.TAPE DECK ADJUSTMENT DECK MODE TEST TAPE TEST POINTADJUSTMENTADJUST FORDECKADJUST PLAY BACKMTT-114SPEAKER Output Azimuth adjusting screw STOPFWD: LEFT L/R Maximum RVSFWD: RIGHT RVS: LEFT 2. RECORD BIAS ADJUSTMENT DECK MODE TEST TAPETEST POINTADJUSTMENTDECKADJUST FOR REC MODEMTT-5511C241L201 AUT

10、O-RVS85kHz5kHz AUTO-STOP60kHz5kHz RadioFans.CN 收音机爱好者资料库 - 2-2 - TROUBLESHOOTING GUIDE 1. CD - 2-3 - OPEN COLOSE NG CONNECTOR LOCKING CHECK DEFECTIVE MAIN POWER SUPPLY CHECK THE(SW502) DEFECTIVE IC503 DEFECTIVE MICOM MECHANISM CHECK LOING CHECK (CN605, CN302) CHECK VOLTAGE CHANGE LO+, LO- OF IC503

11、CHECK POWER SUPPLY CIRCUIT (CN603, CN302) PN508 PIN8 = 6.2V, PIN7 = 5V, PN507 PIN1=5V YES YES YES NO NO NO NO - 2-4 - “READING” DISPLAY CHECK (=ONLY “CD” DISPLAY) - 2-5 - READING OK CHECK (= “ NO DISC ” DISPLAY) CONNECTOR LOCKING CHECK(PN501 ,PN503) DOES SLED MOVE? DOSE LENSE MOVE? (UP&DOWN) DOSE LA

12、SER LIGHT? DOES SPINDLE ROTATE? IS READING OK? CHECK PN501 PIN 14,15 (TA+,TA-) CHECK PN503 PIN5.6 (SP+,SP-) CHECK PN501 PIN 10(LD) CHECK PN501 PIN 15, 16 (FA-,FA+) CHECK PN503 PIN3, 4 (SL+,SL-) DEFECTIVE PICKUP OR IC503 OR IC501 OR IC502 DEFECTIVE PICKUP OR IC503 OR IC501 DEFECTIVE PICKUP OR IC502 D

13、EFECTIVE PICKUP OR IC503 DEFECTIVE PICKUP OR IC503 OR IC501 OR IC502 A B C D E NO NO NO NO NO NO NO NO NO NO YES YES YES YES YES - 2-6 - READING OK CHECK #A(=“NO DISC” DISPLAY) DOSE SL+ WAVEFORM APPEAR AT(IC503 PIN 14 AND PN503 PIN3)WAVEFORM #2 SLED MOTOR WAVE DOSE SLIN WAVEFORM APPEAR AT (IC503 PIN

14、5) WAVEFORM #2 SLED DRIVE WAVE CHECK PN503 CONNECTOR LINE DEFECTIVE IC501 DEFECTIVE IC503 DEFECTIVE PN503 CONNECTOR DEFECTIVE PICUP SLED MOTOR A YES NO NO NO NO NO - 2-7 - READING OK CHECK #B(=“NO DISC” DISPLAY) DOSE FA+ WAVEFORM APPEAR AT(IC503 PIN 1 5 AND PN50 1 PIN 16)WAVEFORM #3 FOCUS COIL DRIVE

15、 WAVE DOSE FAIN WAVEFORM APPEAR AT (IC503 PIN26) WAVEFORM #3 FOCUS DRIVE WAVE CHECK PN50 1 CONNECTOR LINE DEFECTIVE IC50 1 DEFECTIVE IC503 DEFECTIVE PN501 CONNECTOR DEFECTIVE PICUP FOCUS ACTUATOR B YES NO NO NO NO NO - 2-8 - READING OK CHECK #C(=“NO DISC” DISPLAY) IC ?V APPLIED TO PIN 10 OF PN501 LA

16、SER SUPPLY VOLTAGE CHECK IS 3.3V APPLIED TO PIN3 OF IC502 RF IC SUPPLY VOLTAGE CHECK CHECK PN501 CONNECTOR LINE DEFECTIVE IC501 IS 2.0V PIC2 OF IC502 LASER CONTROL VOLTAGE CHECK DEFECTIVE IC501 DEFECTIVE IC503 DEFECTIVE PICUP FOCUS ACTUATOR DEFECTIVE PN501 CONNECTOR C YES YES NO NO NO NO NO NO - 2-9

17、 - READING OK CHECK #D(=“NO DISC” DISPLAY) DEFECTIVE IC501 DEFECTIVE IC503 DEFECTIVE PN503 CONNECTOR DEFECTIVE PICUP SPINDLE MOTOOR CHECK PN503 CONNECTOR LINE D NO NO NO NO DOSE SP+ WAVEFORM APPEAR AT(IC503 PIN 12 AND PN503 PIN6)WAVEFORM #4 SPINDLE MOTOR DRIVE WAVE DOSE SPIN WAVEFORM APPEAR AT (IC50

18、3 PIN6) WAVEFORM #4 SPINDLE DRIVE WAVE YESYES - 2-10 - READING OK CHECK #E(=“NO DISC” DISPLAY) E DOSE TA+ WAVEFORM APPEAR AT(IC503 PIN17 AND PN503 PIN 15)WAVEFORM #5 TRACKING COIL DRIVE WAVE DOSE TAIN WAVEFORM APPEAR AT (IC503 PIN23) WAVEFORM #5 TRACKING DRIVE WAVE CHECK PN503 CONNECTOR LINE DEFECTI

19、VE IC501 DEFECTIVE IC503 DEFECTIVE PN503 CONNECTOR DEFECTIVE PICKUP OR IC502 DEFECTIVE PN503 CONNECTOR DEFECTIVE PICUP SPINDLE MOTOOR DOSE ARF SIGNAL APPEAR? (IC502 PORT8) WAVEFORM#6 DOSE FE, TE SIGNAL APPEAR? (IC502 PORT FE:23,RE:21) WAVEFORM#6 NO NO NO NO NO NO NO YES YES YES - 2-11 - 2. MAIN POWE

20、R Main Power input (AC-cord in) LCD Display “Hello”Check the Voltage-selector 110V/230V (Duble Voltage only) Check the DC out of C813(+)Check the FuseReplace the Fuse Replace the ZD805 Replace the Q810 Check the ZD805 of +13V Replace the IC801 Check the D602, D604, D605 Check the ZD803, Q807 Check t

21、he Q601 Replace the X601, X602 Check the Q810 “E ” DC Power-output Check the D901,D902,D903,D904 Check the DC power output of IC801 pin3 +5.2V Check the power-output IC601 pin17,54,90? Check the DC +5.2V output of Q808 “C” Check the Reset of IC601 pin11, Q601 “C” Check the Oscillation of X601,X602 R

22、eplace the IC601 NO NO NO NO NO NO NO NO NO YES YES YES YES YES YES YES YES YES YES YES - 2-12 - 3. MUTING CIRCUIT(MUTE) 4. FUNCTION MODE AUDIO ABNORMAL Dose “ HIGH ” appear at Q305, Q306 “ B ” Check the “LOW ” of Q305, Q306 “E ” MUTE TAPE CD TUNER Check the signal input of IC301 pin2, 5 Check the s

23、ignal input of IC301 pin1, 6 Check the signal input of IC301 pin3,4 Refer to “Tuner Pack Trouble Shooting ” Check the signal input of PN302 “R-CH ”“L-CH” Refer to “TAPE Trouble Shooting ” Check the “HIGH” of the IC601 pin9 Check the pattern Replace the Q305, Q306 Check the IC601 NO NO NO YES YES YES

24、 YES YES YES YES YES - 2-13 - 5. IC301 Check the IC601 Function Selector Check the Pattern Replace the IC301 Check the IC601 END Check the Power supplying to IC301 pin24 Check the +8.2V DC output ZD302 Check the Data of IC601 pin 6, 7 (CD TAPE Function) Check the CLK Data of IC301 pin 21,22 NO NO NO

25、 NO YES YES YES YES - 2-14 - 6.TUNER PACK Check the Tuner Power of PN101 “Tu- B+” Check the DC output of “HIGH” Q818 “C” Check the “high” Q819 “B ” Check the DC output Q802 “E”, pattern Replace Tuner pack CE : Chip Emable DI : Data Input(From u-com) DO : Data Output(to u-com) CLK :Tuner Mode Clock C

26、heck the PN301 of CE, DI, DO, CLK (PLL) Is the normal? END YES YES YES YES NO NO NO - 2-15 - 7.TAPE DECK Check the power supplying to IC201 pin18 Check the signal output of IC201 pin5,20 Check the “LOW” of Q210, 211 “B ” Check the DC output Q815 “C” Check the “high” IC601 pin92 Replace the Deck Mech

27、a Check the pattern Check the Deck Mecha Replace the IC201 YES YES YES YES NONO NONO Play - 2-16 - REC Check signal supplied to IC201 pin 11, 14 Check the “LOW ” of Q208, 209 ”B” Check the “LOW ” of IC601 pin32 Check the Oscillation of L201 pin1, 3 Replace the deck Check the power supplying to C245(

28、+) Check the “LOW ” Q813 “C” Check the IC601 pin87 Check the DC output of Q811 “C” Check the Oscillation of Q202 “E ” Check the signal of R239, R240 Check the pattern Check the 0.6V of Q203 “B ” Replace the L201 Replace Q208, 209 YES YES YES YES YES YES YES NO NO NO NO NO NO NO - 2-17 - VOLTAGE SHEE

29、T 1 2 3 4 5 6 7 8 9101112 0V 0V 1.3V 1.3V 1.4V 1.7V 0V 4.5V 2V 1.3V 0V 0V 13 14 15 16 17 18 19 20 21 22 23 24 0.8V 0V 1.3V 2V 1.4V 7.8V 7.5V 4V 1.3V 1.3V 0V 0V 1 2 3 4 5 6 7 8 0V 0V 0V 5V 0V 7.8V0V 0V IC201 1 2 3 4 5 6 7 8 9101112 3.9V 4.1V 4.1V 4.1V 4.1V 3.9V 4.1V 4.1V 4.1V 4.1V 4.1V 4.1V 13 14 15

30、16 17 18 19 20 21 2223 24 4.1V 4.1V 4.1V 0V 0V 4.1V 4.1V 0V 0V 0V 4.1V8.2V 25 26 27 28 0V 3.4V 3.4V 4.1V IC301 1 2 3 4 5 6 7 8 9101112 0V 0V 0V 0V 3.3V 0V 0V 0V 0V 0V 0V 0V 13 14 15 16 17 18 19 20 21 22 23 24 0V 3.3V 3.3V 0V 0V 0V 0V 0V0V 0V 0V 0V 25 26 27 28 29 30 31 32 33 34 35 36 0V 0V 0V 1.5V 1.

31、5V 0V 0V 0V 0V 0V 1.6V 0V 37 38 39 40 41 4243 44 45 46 47 48 1.7V 0V 3.3V 1.6V 1.6V 1.6V 1.6V 1.6V 1.6V 3.2V0V 0V 49 50 51 52 53 54 55 56 57 58 59 60 0V 3.2V 0.8V 1.6V 1.6V 3.2V 1.4V 1.4V 0V 1.6V 0V 1.6V 61 62 63 64 65 66 67 68 69 70 71 72 3.2V 0V 0V 0V 0V 0V 1.5V 0V0V 0V 0V 2.5V 73 74 75 76 77 78 7

32、9 80 81 82 83 84 0.25V 2.7V 0.25V 0V 0V 0V 1.6V 0V 2.7V 3.2V 0V 1.2V 85 86 87 88 89 90 91 92 93 94 95 96 1.6V 3.2V 1.6V 0V 0V 0V 0V 0V 0V 0V 0V 0V 97 98 99 100 0V 3.2V 0V 0V IC501 1 2 3 4 5 6 7 8 9101112 10.7V 6.1V 11V 5.8V 0.4V 0V 0V 0.7V 0V 9.1V 10.8V 12V IC302 IC202 - 2-18 - 1 2 3 4 5 6 7 8 91011

33、12 0V 2.1V 3.2V 0V 2.3V2V 1.6V 1.5V 1.5V 1.5V2V 1V 13 14 15 16 17 18 19 20 2122 23 24 0V 0V 0V 3.2V 0V 1.6V 1.6V 1.6V 1.6V 1.6V 1.6V 0V 25 26 2728 29 30 31 32 1.6V 1.6V 1.6V 1.6V 1.6V 1.6V 1.6V 1.6V IC502 1 2 3 4 5 6 7 8 9101112 0V 0V 1.2V 3.5V 1.6V 1.5V 6.3V6.3V 0V 0V 3.6V 3V 13 14 15 16 17 18 19 2

34、0 21 22 23 24 3.3V 3.3V 2.9V 3.5V 3.2V 3.2V 0V 6.3V 3.5V 1.6V 1.6V 1.6V 25 26 27 28 1.6V 1.6V 1.6V 1.6V IC503 1 2 3 4 5 6 7 8 9101112 3.2V 0V 0V 0V 0V 0V 3.2V 0V 0V 0V 0V 0V 13 14 15 16 17 18 19 20 21 22 23 24 3.2V 3.2V 3.2V 3.2V 3.2V 3.2V 0V 0V 0V 0V 0V 0V 25 26 2728 29 30 31 3233 34 35 36 3.2V 0V

35、0V 0V 0V 0V 0V 0V 0V 3.2V 0V 3.2V 37 38 39 40 41 42 43 44 45 46 47 48 0V 3.2V 0V 0V 0V 0V 0V 3.2V 0V 0V 0V 0V 49 50 0V 0V IC504 1 2 3 4 5 6 7 8 9101112 4.4V 4.8V 4.8V 4.7V 4.7V 5.4V 0V 4.8V 4.8V 4.8V 2.3V 2.5V 13 14 15 16 17 18 19 20 21 22 23 24 0V 2.3V 2.4V 4.8V 4.8V 4.8V 0V 4.8V 4.8V 4.8V 0.3V 0.3

36、V 25 26 27 28 29 30 31 32 33 34 35 36 0V 0.4V 0V 0V 0V 0V 0V 4.9V 0.1V 4.8V 0V 4.9V 37 38 39 40 41 42 43 44 45 46 47 48 0V 0V 0V 4.7V0V 0V 0.4V 4.9V 0V 4.9V 0V 0V 49 50 51 52 53 54 55 56 57 58 59 60 4.7V 0V 0V 4.8V0V 0V 4.9V 0V 0V 0V 0V 0V 61 62 63 64 65 66 67 68 69 70 71 72 0V 4.8V 4.8V 0V 0V 0V 0V

37、 0V 0V 0V 4.8V 0V 73 74 75 76 77 78 79 80 0V 0.2V 0.7V0.1V 0V 0V 0V 4.8V IC601 - 2-19 - E CB 0V 0V 13.7V Q201 E CB 14V 14.3V 14.3V Q202 E CB 0V 13.9V0V Q203 E CB 12.5V 12.5V 11.6V Q308 E CB 0V 3.8V 11.7V Q309 E CB 1.4V 6.4V 6.4V Q802 E CB 12.5V 12.5V 11.6V Q307 E CB 0V 4.9V 0V Q310 E CB 0V 4.9V 4.9V

38、 Q311 E CB 0V 6.4V 4.3V Q803 E CB 6.5V 9.9V 7V Q804 E CB 0V 0V 0.6V Q807 E CB 5.2V 5.2V 4.6V Q808 E CB 10V 13V 10.6V Q810 E CB 11.6V 12.3V 12.3 Q811 E CB 0V 0V 0.6V Q813 E CB 8.8V 9.5V11.8V Q814 E CB 8.2V 8.9V 8.9V Q815 E CB 8.3V 9V 9V Q818 E CB 0V 0V 4.3V Q819 E CB 8.7V 9V8V Q820 E CB 0V 14.4V 14.4

39、V Q204 E CB 14.4V 14.4V 13.6V Q205 E CB 0V 0V 3.8V Q206 E CB 0V 14V 0V Q207 E CB 0V 0V 0.6V Q208 E CB 0V 0V 0.6V Q209 E CB 0V 0V 0.6V Q210 E CB 0V 0V 0.6V Q211 - 2-20 - E CB 1.9V 2.85V 2.2V Q501 E CB 3.3V 3.3V 2.5V Q502 E CB 3.3V 0V 4.4V Q503 E CB 0V 4.8V 0V Q601 E CB 0V 0V 0.6V Q602 E CB 0V 0.2V 4.

40、7V Q603 E CB 3.9V 4.5V 4.5V Q604 E CB 0V 0V 4.5V Q605 E CB 5.5V 5.5V 0V Q606 E CB 0V 0V 0V Q504 E CB 0V 0V 0V Q505 E CB 0 0 0.6V Q607 E CB 0.2V 10V 5V Q801 BLOCK DIAGRAM 2-212-22 2-232-24 SCHEMATIC DIAGRAMS 1. MAIN SCHEMATIC DIAGRAM (POWER/EQ/AMP) 2-252-26 2. FRONT/MICOM SCHEMATIC DIAGRAM 2-272-28 3

41、. DECK SCHEMATIC DIAGRAM 2-292-30 4. CDP SCHEMATIC DIAGRAM 2-312-32 PRINTED CIRCUIT DIAGRAM 1. MAIN P.C. DIAGRAM (SOLDER SIDE) 2-332-34 1. MAIN P.C. DIAGRAM (COMPONENT SIDE) 2-352-36 2. FRONT P.C. DIAGRAM (SOLDER SIDE) 2-372-38 2. FRONT P.C. DIAGRAM (COMPONENT SIDE) 2-392-40 3. BATTERY/POWER P.C. DI

42、AGRAM 2-412-42 4. CD-MP3 P.C. DIAGRAM 2-432-44 WIRING DIAGRAM 3-13-2 SECTION 3. EXPLODED VIEWS A46 282 290 291 351 355 A41 450 268 A26 268 268 268 267 270 A43 280 253 252 251 250272 254 255 256 257A00 258 271 263 262 266 264 260 261 261 260 265 NOTE) Refer to “SECTION 4 REPLACEMENT PARTS LIST” in order to look for the part number of each part. MEMOMEMO