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LX-221A/D/X, LXS-221
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[CONTENTS]
SECTION 1. GENERAL
SERVICING PRECAUTIONS ..................................................................................................... 1-2 ESD PRECAUTIONS ................................................................................................................. 1-4 SPECIFICATION ........................................................................................................................ 1-5
SECTION 2. TROUBLESHOOTING
ADJUSTMENTS ......................................................................................................................... 2-1 TROUBLESHOOTING ............................................................................................................... 2-3 WAVEFORMS OF MAJOR CHECK POINT ............................................................................... 2-7 BLOCK DIAGRAM .................................................................................................................... 2-16 SCHEMATIC DIAGRAMS ........................................................................................................ 2-18 WIREING DIAGRAM ................................................................................................................ 2-26 PRINTED CIRCUIT DIAGRAMS .............................................................................................. 2-28 INTERNAL BLOCK DIAGRAM OF ICs .................................................................................... 2-39 PRINTED CIRCUIT DIAGRAMS .............................................................................................. 2-53
SECTION 3. EXPLODED VIEWS
CABINET AND MAIN FRAME SECTION ................................................................................... 3-1
SECTION 4. SPEAKER SECTION
SPEAKER SECTION................................................................................................................... 4-1
SECTION 5. REPLACEMENT PARTS LIST
REPLACEMENT PARTS LIST .................................................................................................... 5-1
- 1-1 -
SECTION 1. GENERAL
SERVICING PRECAUTIONS
[NOTES REGARDING HANDLING OF THE PICK-UP]
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
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!
NEVER look directly at the laser beam, and dont let contact fingers or other exposed skin.
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
Magnet Pressure Pressure
How to hold the pick-up Cotton swab
Conductive Sheet
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 - 1-2 -
[NOTES REGARDING COMPACT DISC PLAYER REPAIRS]
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.
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 (1M ) 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 Mohm)
Conductive Sheet
Resistor (1 Mohm)
CLEARING MALFUNCTION
You can reset your unit to initial status if malfunction occur(button malfunction, display, etc.). Using a pointed good conductor(such as driver), simply short the RESET jump wire 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.
VOLUME RESET jump wire
2. If you wish to operate the RESET jump wire, it is necessary to unplug the power cord.
UP
VOLUME KNOB
DOWN
- 1-3 -
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.
- 1-4 -
SECTION 2. ELECTRICAL SECTION
ADJUSTMENTS
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.
TAPE DECK ADJUSTMENT
1. AZIMUTH ADJUSTMENT
Deck Mode Palyback Test Tape MTT-114 Test Tape Speaker Out
Electronic Voltmeter Head L ch Test Tape MTT-114 R ch Unit Playback Mode L out Speaker Out CH1 CH2 GND R out
Adjustment DECK Screw Azimuth Screw
Dual-trace synchroscope
Adjust for Maximum
Figure 1. Azimuth Adjustment Connection Diagram
2. MOTOR SPEED ADJUSTMENT
Deck Mode Rec/Pause Test Tape MTT-5511
Head Test Tape MTT-5511 Record/Playback head
Test Tape ERASE HEAD WIRE(PN201)
Record/Playback and Pause Mode
Adjustment L201
PN202
Adjust for 60kHz±5kHz (Auto stop) 85kHz±5kHz(Auto Reverse)
Frequency Counter
Unit GND
Figure 2. Motor Speed Adjustment Connection Diagram
- 2-1 -
3. TUNER ADJUSTMENT
(FM)
Item DC Voltage Test Point Check Point TP1, TP2
FM Antenna Terminal
Adjustment L101
Adjust for 0V±50mV
Electronic OSCILLOSCOPE
Signal Generator
Speaker
Unit GND
Figure 3. Tuner(S curve) Adjustment Connection Diagram
- 2-2 -
TROUBLESHOOTING
CD PART
Turn power on.
Is power on?
NO
Check power supply circuit. PN508 PIN8, 6.2V PN508 PIN7, 5V IC503 PIN2, 3.3V
NO
Does initial read work?
NO
Check the DISK circuit YES Check the Laser YES Check the focus circuit YES Check the TRAKING servo. NO
NO
Check the connector PN503, PN504, PN507
NO
Does it play?
Check the tracking servo.
NO
Does it output audio? NO
NO
Check the PN508 PIN1, 3
OK
- 2-3 -
FAILS TO INITIAL READ Disc motor turns YES Does RF waveform appear? IC501 Pin3 NO NO Check the Voltage change of PN 507 PIN2(OPEN, CLOSE) YES Check the Data transferred from PN507 pin8 to CD DSP
5V 0V
NO
Defective connector PN507
NO
Defective connector PN507, Defective MICOM
YES Check the Data transferred from PN507 pin6 to MICOM
5V 0V
NO
Defective connector PN507, Defective IC501
YES SLDO Voltage (IC501 pin23) YES YES Check the change of SL +, SL - Voltage (IC502 pin 18, 19)
2V 1V 0V
NO
Defective IC501
1.2V 0V 0.8V
NO
Defective IC502
YES Does laser light? YES Does FA+ waveform appear at IC502 pin18? focus coil drive wareform. YES Does TE waveform appear at IC501 pin15? TRACKING ERROR wareform YES Is rotation normal? NO YES Is there no dropout of RF signal? YES
A
Defective contact PN503 Defective PICK-UP
B
Defective IC501 Defective PICK-UP
- 2-4 -
Laser does not light.
Is 3.5V applied to pin80 of IC801? YES NO Did pickup return to innermost circular? YES NO Is data transferred from MICOM IC ? YES Does voltage appear at IC 502 pin18, 19? NO
Defective MICOM.
NO
Defective IC501, 502
YES
Defective slide motor and/or connector.
Does it stop at inner pick circular after shift? YES
Is defect output from LM SW applied to pin 5 of PN503? OPEN CLOSE YES
NO
Defective LMT SW and/or connector.
Defective MICOM.
YES Is power supplied to laser Q501? (Q501 collector: about 1.8V) YES Does laser current flow? (R508s voltage are 1.0V) NO Defective connector. YES
R508 »1.0V
Defective Q 501 and/or laser. Defective laser and/or connector.
R508 «1.0V
YES
- 2-5 -
B
Laser lights
Does lens move up/down? YES
NO Check the signal of FOCUS SEARCH (IC501 Pin 21)
NO
Defective IC501
YES Chekc the signal of PN502 pin 13, 14 NO
Defective IC502
YES
Open activator and/or connector
Does FE signal appear? (IC501 pin 13) YES
NO
Defective IC501
Does DRF signal appear? (IC501 pin67)
NO
Degraded laser diode Defective PICK-UP
- 2-6 -
WAVEFORMS OF MAJOR CHECK POINT
1. HF signal (RF signal ) waveform (IC501 pin4) during normal play 2. EFM signal (IC501 pin 3)waveform during Normal Play
( 0.5V/Div. 500nS/Div.
OV
( 0.5V/Div. 5µS/Div.
OV
3. Focus coil drive waveform(IC502 pin13) When focus search failed or there is no disc on the tray
Focus coil drive waveform(FDO: IC501 pin21) and DRF(IC501 pin67) when focus search is accomplished
( 1S/Div. 1V/Div.
OV
OV (CH1)
OV (CH2) CH1 : FOCUS COIL DRIVE SIGNAL 2V/Div. CH2 : DRF (2) When time division 1mS/Div, 1V/Div (During forward track traverse)
4. Tracking coil drive waveform and TE during track traverse (1) When time division is 20mS/Div.1V/Div.
(
OV (CH1) OV (CH2)
OV (CH1) OV (CH2)
(
CH1 : TRACKING COIL DRIVE (IC502 pin27) CH2 : TRACKING ERROR (TE: IC501 pin15)
(
CH1 : TRACKING COIL DRIVE (IC502 pin27) SIGNAL 2V/Div. CH2 : TRACKING ERROR (TE: IC501 pin15) 1V/Div.
(3) When time division is 0.5nS/div. (During backward Track Traverse)
5. Feed motor drive waveform(IC 502 pin18) During normal play
( 1mS/Div. 1V/Div.
OV OV (CH2) CH1 : TRACKING COIL DRIVE SIGNAL 2V/Div. (IC502 pin27) CH2 : TRACKING ERROR(TE: IC501 pin15) 1V/Div.
( 2S/Div. 0.5V/Div.
OV
(
- 2-7 -
P-SENS PART
Does +5V appear at ZD702? YES Check the pattern of IC301 Pin 26 . NO Check the waveform of D706(+). YES NO Replace the D706
Check the R718 and replace ZD 702
VKK PART
Does DC - 27V appear at PN303 Pin 20 . YES NO Dose -27V appear at ZD601(-) YES NO
OK
Check the TURN ON Check the -27V(Lower) of C603(-)
Replace the D601, D602
Replace the Q601 Refer to power circuit OK
- 2-8 -
POWER CIRCUIT
Check the Fuse YES Check the DC output of C715(+), C716(-) YES Check the DC 12V Input of IC702 YES NO NO Replace the Fuse Check the power YES Replace the D701, D702, 703, 704 NO Replace the Transformer
Check the DC 6.2V output of IC704 YES Check the DC 12V Output of IC703 YES Check the Collector (5.6V) of Q704 (CD FUNCTION) NO Check the Pattern of IC702 and IC704
NO
Check the High of IC703 pin4 YES Replace the IC703 Refer to IC401 TROUBLESHOOTING
Check the LOW of IC401 pin8
OK
- 2-9 -
MUTING CIRCUIT (MUTE)
Dose High appear at Q701, Q751 B NO YES NO Refer to IC203 Troubleshooting (ONLY Q201/Q251) Check the High of Q702 E YES check the LOW Q701, Q751, C YES MUTE NO Refer to IC301 Troubleshooting
Replace the Q702 Replace the TR
AUDIO ABNORMAL
Check the output of IC701 Pin 2, 4 YES Check the input of IC701 pin7, 11 YES Check the DC 10V of IC400 PIN24 YES Check the DC 12V Output of IC702 YES Power check NO Check the FUNCTION input terminal NO Check the speaker connector
- 2-10 -
FUNCTION MODE AUDIO ABNORMAL
TAPE
AUX
Check the signal input of IC400 pin 7, 28
Chekc the signal input of IC400, pin 1, 6
Refer to IC200 Troubleshooting
Check the signal input of JK400
CD
TUNER
CHECK THE SIGNAL INPUT OF IC400 PIN 3, 4
Check the signal input of IC400 pin 2, 5
Check the signal CN500 Pin 1, 3 or Refer to CD Troubleshooting
Refer to IC102 Troubleshooting
IC301 TROUBLESHOOTING
Check the power supplying IC301 Pin 17, 46, 90? YES NO Refer to Power Circuit Troubleshooting
Check the High of IC301 pin26 YES Check the oscillation of X301 YES NO Replace the X301 NO Check the P-SENS
When power supplying to IC301 pin12. (Low High) NO YES Replace the IC301 Check the RESET circuit
- 2-11 -
IC203 TROUBLESHOOTING
Check the power supplying to IC400 pin24 YES NO Refer to Power Circuit Troubleshooting
Check the CLK Data of IC400 pin 21, 22 YES NO Check the Data of IC301 Pin 9, 10 (CD TAPE FUNCTION) Refer to IC301 Troubleshooting
Check the CONTROLL function NO YES END Replace the IC400 Check the pattern of (IC301, IC400)
FM (TUN101)
Check the 12V input of TUN101 B+ 6 YES Check the 12V of Q102 E YES NO Refer to Power Circuit Trouble-shooting
Check the GND of IC103 Pin 7 Check the High Voltage of TUN101 VT 5 YES Replace the Q102 YES Replace the TUN101 NO Refer to IC103 Troubleshooting
Check the OSC waveform of TUN101 Pin 8 YES Refer to IC102 Troubleshooting Replace the TUN101
- 2-12 -
IC102 TROUBLESHOOTING
Is power supplied to pin8 YES NO Refer to Power Circuit Troubleshooting
Check the waveform of Pin 20, 21 NO YES Check the output of Pin 16, 17 NO YES Check the FM(TUN101) & AM(L107) NO Replace the IC102
Check the Low of Pin 13 NO YES Refer to IC103 Troubleshooting
END
Replace the IC102
IC103 TROUBLESHOOTING
Check the power supplying to pin 17 YES NO Refer to Power Circuit Troubleshooting
Check the oscillation of X104 YES NO Replace the X104 Check the line or refer to IC 301 Troubleshooting CE: Chip Enable DI: Data Input(from u-com) DO: Data Output(to u-com) CLK: Tuner mode clock Replace the IC103
Check the waveform of CE, DI, DO, CLK NO YES Is the normal ? YES END NO
- 2-13 -
AMCOIL TROUBLESHOOTING
Check the High of L107 Pin 2 NO YES Check the oscillation of L107 Pin 13 NO YES Refer to IC102 Troubleshooting Replace the L107 Refer to IC103 Troubleshooting
Play
Check the VCC supplying to IC201 pin 4 NO YES Check the signal output of IC201 pin 3, 6 NO YES Check the Low of Q201, 251 B Check the Deck Mecha YES NO Replace the Deck Mecha. Refer to Power Circuit Troubleshooting
Replace the IC201
- 2-14 -
REC (Q252, Q202 ON / R273, R223 High)
Check signal supplied to IC203 pin 2, 8? NO YES Check the Low of Q202, Q252 B YES Replace the Q202, Q252 Check the output of IC203 Pin3, 7 NO YES Check the High of IC203 pin6 NO YES Check the oscillation of L201 pin1, 3 YES Replace the DECK YES Check the oscillation of Q204, E NO Check the 0.6V of Q205 B NO Check the power supplying to C227(+) NO Refer to Power Circuit Troubleshooting Check the power or Refer to IC203 Troubleshooting Check the Vcc power of IC203 Pin6
NO
Refer to IC203 Troubleshooting
YES
Check the 0.6V of Q205 B NO YES OK Check the IC401 pin12 or Replace the L203
- 2-15 -
CD MAIN P.C. BOARD (SOLDER SIDE)
- 2-36 -
CD MAIN P.C. BOARD (COMPONENT SIDE)
- 2-37 -
POWER P.C. BOARD
- 2-38 -
INTERNAL BLOCK DIAGRAM OF ICs
BU1923F (IC 302)
FEATURES
RDS / RBDS compatible FM receivers for American and European markets, car stereos, high-fidelity stereo systems and components, and FM pagers.
Low Dropout Voltage Regulator
EQIALENT CIRCUIT
- 2-39 -
Pin descriptions
LA1837 (IC 102)
Single-Chip Home stereo IC with Electronic Tuning Support
The LA1837 is a single-chip AM/FM IF and MPX IC that supports electronic tuning and was developed for use in home stereo systems. It is optimal for use in automatic station selection systems that use the SD and IF counting techniques.
Block Diagram
FM SD ADJ
3 rd 5 th DECODER ANTI-BIRDIE
- 2-40 -
FM
LC72131 (IC 103)
AM/FM PLL Frequency Synthesizer
BA3126N (IC 201)
2-channel head switch for radio cassette recorders
BA3308 (IC203) Dual preamplifier with ALC
APPLICATIONS
Stereo radio cassette recorders, cassette decks and home stereo systems and music centers
- 2-41 -
TDA7440D (IC 701)
DESCRIPTION
TONE CONTROL DIGITALLY CONTROLLED AUDIO PROCESSOR
The TDA7440D is a volume tone (bass and treble) balance (Left/Right) processor for quality audio applications in Hi-Fi systems.
BLOCK DIAGRAM
- 2-42 -
BU2090F (IC401) 12-bit, serial IN, parallel OUT driver
APPLICATIONS
Radio casstte players, telephones, compact audio systems, car stereos, and others
- 2-43 -
FAN8039BD3 (IC 802)
5-CH MOTOR DIVER DESCRIPTION
The FAN8039BD3 is a monolithic integrated circuit suitable for a 5-CH motor driver which drives the tracking actuator, focus actuator, sled motor, tray motor, spindle motor of the DVDP/CAR-CD systems.
DO 3 + DO 5+ GND3 DO 4+ VCC1 DO4VREF FIN (GND) GND2 DO 5DO 3VCC IN3 PS
28
IN4
27
2
26
2
25
24
23
22
21
10K PS RESX FUNCTION All Active Reg. Only Deactive Reg. Only Active All Deactive
20
19
2
18
2
17
16
15
Level Shift
H 10K H L L
H L H L
10K
Level Shift
Level Shift
Regulator
2.5V 10K 10K
Level Shift
TSD
COMP
Level Shift
2
2
10K
2
2
1
DO1-
2
DO1+
3
IN1
4
REGVCC
5
REB
6
REO
7
RESX FIN (GND)
8
GND1
9
CTL
10
FWD
11
REV
12
IN2
13
DO 2+
14
DO 2-
Pin Definitions
NO 1 2 3 4 5 6 7 8 9 10 11 12 13 14 Symbol DO1DO1+ IN1 REGVCC REB REO RESX GND1 CTL FWD REV IN2 DO2+ DO2Description CH1 Drive Output (-) CH1 Drive Output (+) CH1 Drive Input Regulator Supply Voltage Regulator Output Regulator Feedback Input Regulator Reset Signal Ground CH5 Motor Speed Control CH5 Forward Input CH5 Reverse Input CH2 Drive Input CH2 Drive Output (+) CH2 Drive Output (-) NO 15 16 17 18 19 20 21 22 23 24 25 26 27 28 Symbol GND2 DO5+ DO5DO3DO3+ IN3 VCC1 PS VREF VCC IN4 DO4+ DO4GND3 Description Power Ground1 (CH 2,3,5) CH5 Drive Output (+) CH5 Drive Output(-) CH3 Drive Output(-) CH3 Drive Output (+) CH3 Drive Input Supply Voltage1(CH2,CH3,CH5) Power Save Bias Voltage Supply Voltage(CH1,CH4) CH4 Drive Input CH4 Drive Output (+) CH4 Drive Output (-) Power Ground2 (CH 1,4)
- 2-44 -
KA78R33 (IC 803)
DESCRIPTION
Low Dropout Voltage Regulator
The KA78R33 is a low-dropout voltage regulator suitable for various electronic equipments. It provides constant voltage power source with TO-220 4 lead full mold package. Dropout voltage of KA78R33 is below 0.5V in full rated current(1A). This regulator has various function such as peak current protection, thermal shut down, overvoltage protection and output disable function.
INTERNAL BLOCK DIAGRAM
Vin 1 Q1 2 Vo
THERMAL SHUTDOWN
OVERVOLTAGE PROTECTION
BANDGAP REFERENCE
+ R1
SOA PROTECTION HIGH / LOW Vdis 4 + OUTPUT ON / OFF
1.4V
- CIRCUIT SHORTCIRCUIT PROTECTION
R2
3 GND
BLOCK DIAGRAM
XIN XOUT
REFERENCE DIVIDER
PHASE DETECTOR CHARGE PUMP
PD
AIN FMIN 1 2 SWALLOW COUNTER 1/16. 1/17 4bits UNLOCK DETECTOR AOUT
AMIN
12bits PROGRAMMABLE DIVIDER
CE DI CL D0 POWER ON RESET CCB I/F
DATA SHIFT REGISTER LATCH
UNIVERSAL COUNTER
IFIN
VDD VSS
B01
B02
B03
B04
I01
I02
- 2-45 -
TDA7265 (IC701) 25+25W STEREO AMPLIFIER WITH MUTE & ST-BY
DESCRIPTION The TDA7265 is class AB dual Audio power amplifer assembled in the Multiwatt package, specially designed for high quality sound application as Hi-Fi music centers and stereo TV sets.
PIN CONNECTION (TOP View)
- 2-46 -
KIA7805, 7812API (IC 703, IC 782, IC 783)
LOW DROPOUT VOLTAGE REGULATOR FEATURES
Suitable for CMOS, TTL, the Other Digital ICs Power Supply. Internal Thermal Overload Protection. Internal Short Circuit Circuit Current Limiting. Output Current in Excess of 1A Satisfies IEC65 Specification. (International Electronical Commission.)
EQIALENT CIRCUIT
- 2-47 -
SECTION 4. SPEAKER SECTION
MODEL: LXS-220
850
862 851 853 852
855 864 859 857
854 863 856
861
858
- 4-1 -
BLOCK DIAGRAM
NOTE: Warning Parts that are shaded are critical With respect to risk of fire or electrical shock.
2-16
2-17
SHEMATIC DIAGRAMS
MAIN SHEMATIC DIAGRAMS
NOTE: Warning Parts that are shaded are critical With respect to risk of fire or electrical shock.
2-18
2-19
FRONT SHEMATIC DIAGRAMS
2-20
2-21
TUNER & DECK SHEMATIC DIAGRAMS
2-22
2-23
CDP SHEMATIC DIAGRAMS
2-24
2-25
WIRING DIAGRAM
2-26
2-27
PRINTED CIRCUIT DIAGRAMS
MAIN & TUNER P.C. BOARD (SOLDER SIDE)
2-28
2-29
MAIN & TUNER P.C. BOARD (COMPONENT SIDE)
2-30
2-31
FRONT P.C. BOARD (SOLDER SIDE)
2-32
2-33
FRONT P.C. BOARD (COMPONENT SIDE)
2-34
2-35
SECTION 3. EXPLODED VIEWS
CABINET AND MAIN FRAME SECTION
NOTE) Refer to SECTION 4 REPLACEMENT PARTS LIST in order to look for the part number of each part.
A26 459
351
459 257 274 A41
459
A46
301
459
454 272
311
355 250 264
267
310 451 450 454 304 450 304 305 451 A47
260 285 A43 454 454 356 284
303 454 A00 302
286
306
278 279
3-1
3-2
TAPE DECK MECHANISM: AUTO STOP DECK(OPTIONAL)
4 00 5 05 4 04 0 20 0 19 0 18 0 16 0 17 0 21
0 06
4 00 0 02
0 03 0 04 0 05 0 07 0 22
0 08
4 02
0 14
A01
4 05 0 10 0 09 4 01 5 02 5 01 0 15 0 23
0 26
4 03
0 24 5 04 0 25
0 13
0 32 4 01 5 03 0 11 4 00 4 06 4 09 4 08 0 30 0 29 0 28 4 01 0 31 0 27
4 07
3-3
3-4
TAPE DECK MECHANISM: AUTO REVERSE DECK
400 505 404 020 019 018 016 017 021
006
400 002
003 004 005 007 506 022 037
008
402
014 508 507
A0 1
405 010 009 401 502 501 015 023
026
403
024 504 025
013
032 038 027
401 503 031 011 400 409 410 036 035 034 406 039
040
028
029
3-5
3-6
CD MECHANISM
001 002 429 003 A01
429 004 026 430 012 430 012 430 012
430 012
A03
013
014
018 020
017
A02
015 011 431
430
3-7
3-8