SERVICE MANUAL MODEL: LPX-M930A

CD/RADIO CASSETTE RECORDER SERVICE MANUAL

MODEL: LPX-M930A

[CONTENTS]
SECTION 1. GENERAL
ESD PRECAUTIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-2 SPECIFICATIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-3 IDENTIFICATION OF CONTROLS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-4

SECTION 2. ELECTRICAL
ADJUSTMENTS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-1 TROUBLESHOOTING GUDIE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-2 WAVEFORMS OF MAJOR CHECK POINT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-6 INTERNAL BLOCK DIAGRAM OF ICs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-13 VOLTAGE SHEET . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-19 BLOCK DIAGRAM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-21

SCHEMATIC DIAGRAM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-23 PRINTED CIRCUIT DIARGAMS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-31 WIRING DIAGRAM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-37

SECTION 3. EXPLODED VIEWS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-1 SECTION 4. SPEAKER SECTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-1 SECTION 5. REPLACEMENT PARTS LIST . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-1

- 1-1 -

SECTION 1. GENERAL
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 EXCLAMATION POINT WITHIN AN EQUILATERAL TRIANGLE IS INTENDED TO ALERT THE SERVICE PERSONNEL TO THE PRESENCE OF IMPORTANT SAFETY INFORMATION IN SERVICE LITERATURE.

- 1-2 -

 SPECIFICATIONS

- 1-3 -

 IDENTIFICATION OF CONTROLS
Front Panel

- 1-4 -

Rear Panel/Display Window

Remote control

- 1-5 -

MEMO

- 1-6 -

SECTION 2. ELECTRICAL
ADJUSTMENTS

- 2-1 -

 TROUBLESHOOTING

- 2-2 -

- 2-3 -

- 2-4 -

- 2-5 -

 WAVEFORMS OF MAJOR CHECK POINT

- 2-6 -

- 2-7 -

- 2-8 -

- 2-9 -

- 2-10 -

- 2-11 -

- 2-12 -

 INTERNAL BLOCK DIAGRAM OF ICs

- 2-13 -

 System Block Diagram

- 2-14 -

 Pin Assignment

- 2-15 -

- 2-16 -

I IC601 TD7440D
Pin Assignment
R_IN3 R_IN2 R_IN1 L_IN1 L_IN2 L_IN3 L_IN4 MUXOUTL IN(L) MUXOUT(R) IN(R) BIN(R) BOUT(R) BIN(L) 1 2 3 4 5 6 7 8 9 10 11 12 13 14
D98AU884

28 27 26 25 24 23 22 21 20 19 18 17 16 15

R_IN4 LOUT ROUT AGND VS CREF SDA SCL DIG-GND TREBLE(R) TREBLE(L) N.C. N.C. BOUT(L)

Block Diagram
MUXOUTL L-IN1 4 100K 5 L-IN2 100K 6 100K 7 100K 0/30dB 2dB STEP 100K 2 100K 1 VREF 100K 28 R-IN4 100K INPUT MULTIPLEXER + GAIN 10 MUXOUTR INR 11 19 TREBLE(R) 12 BIN(R) SUPPLY RB 13 BOUT(R) 23 CREF
D98AU883

INL 9

TREBLE(L) 18

BIN(L) 14 RB

BOUT(L) 15

L-IN3

VOLUME

TREBLE

BASS

SPKR ATT LEFT

27

LOUT

L-IN4

21 I CBUS DECODER + LATCHES

SCL SDA DIG_GND

R-IN1

22 20

R-IN2

VOLUME

TREBLE

BASS

SPKR ATT RIGHT

26

ROUT

R-IN3

24 25

VS AGND

- 2-17 -

I IC700 LA4631
Block Diagram

- 2-18 -

 VOLTAGE SHEET
SYSTEM CONTROL PART DECK PART.

- 2-19 -

 CD PART

- 2-20 -

 BLOCK DIAGRAM

2-21

2-22

 SCHEMATIC DIAGRAMS
1. MAIN SCHEMATIC DIAGRAM

2-23

2-24

2. FRONT/MICOM SCHEMATIC DIAGRAM

2-25

2-26

3. TUNER SCHEMATIC DIAGRAM

2-27

2-28

4. CDP SCHEMATIC DIAGRAM

2-29

2-30

 PRINTED CIRCUIT DIAGRAM

2-31

2-32

1. MAIN P.C. DIAGRAM (SOLDER SIDE)

2-33

2-34

2. CD P.C. DIAGRAM

2-35

2-36

 WIRING DIAGRAM

2-37

2-38

SECTION 3. EXPLODED VIEWS

383 387

386 388 382 305 A26

335

251 258 250 255

252 304 385 381 A41 303 451 310

257 376 253 375 254 264 275 255 451 289 451

256

351 277 278 276 284 290 291 290

A00

350

SECTION 4. SPEAKER SECTION

851

852

856 850 854

853

- 4-1 -

MEMO

- 4-2 -