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ORDER NO. MD0703022CE CD Stereo System SA-AK750PL Colour (K)... Black Type Notes: This model’s CD mechanism changer unit is CRS1. Please refer to the original Service Manual (Order No. MD0509368C0) for this mechanism. Specifications n AMPLIFIER SECTION Frequency range 87.9 to 107.9 MHz (200 kHz...
SA-AK750PL Motor DC servo motor Supported audio file format Recording system AC bias 100 kHz MP3 bit rate Erase system AC erase 100 kHz USB memory port Tape speed 4.8 cm/s Maximum current 500 mA Overall frequency response (+3, -6 dB) at DECK OUT...
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SA-AK750PL 9.3. Reliability Test Mode (CRS1 Mechanism) 15.5. Main P.C.B. 9.4. Error code Table Display 15.6. Deck P.C.B. 10 Assembling and Disassembling 15.7. Waveform Chart 10.1. Caution 16 Wiring Connection Diagram 10.2. Disassembly flow chart 17 Block Diagram 10.3. Main Parts Location 17.1.
SA-AK750PL 1 Safety Precautions 1.1. General Guidelines 1. When servicing, observe the original lead dress. If a short circuit is found, replace all parts which have been overheated or damaged by the short circuit. 2. After servicing, ensure that all the protective devices such as insulation barriers and insulation papers shields are properly installed.
SA-AK750PL 1.3. Protection Circuitry The protection circuitry may have operated if either of the following conditions are noticed: · No sound is heard when the power is turned on. · Sound stops during a performance. The function of this circuitry is to prevent circuitry damage if, for example, the positive and negative speaker connection wires are “shorted”, or if speaker systems with an impedance less than the indicated rated impedance of the amplifier are used.
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SA-AK750PL semiconductor “chip” components. The following techniques should be used to help reduce the incidence of component damage caused by electro static discharge (ESD). 1. Immediately before handling any semiconductor component or semiconductor-equiped assembly, drain off any ESD on your body by touching a known earth ground.
SA-AK750PL 3 Handling Precautions For Traverse Deck The laser diode in the traverse deck (optical pickup) may break down due to potential difference caused by the static electricity of clothes or our human body. So, be careful of electrostatic breakdown during repair of the traverse deck (optical pickup).
SA-AK750PL 4 Precaution of laser diode CAUTION: This unit utilizes a class 1 laser diode in the optical pickup unit . Invisible laser radiation is emitted from the optical pickup lens. Wavelength: 780nm When the unit is turned on: 1. Do not look directly into the optical pickup lens.
SA-AK750PL 5 Warning 5.1. Service caution based on legal restrictions 5.1.1. General description about Lead Free Solder (PbF) The lead free solder has been used in the mounting process of all electrical components on the printed circuit boards used for this equipment in considering the globally environmental conservation.
SA-AK750PL 8 New Features 8.1. Using the Music Port & Connecting and Playing a USB Mass Storage Class Device This feature enables you to enjoy music from a portable audio equipment.
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SA-AK750PL With reference to page 15 of the operating instruction manual.
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SA-AK750PL With reference to page 16 of the operating instruction manual.
SA-AK750PL 9 Self diagnosis and special mode setting This unit is equipped with functions for checking and inspecting namely: Self-Diagnostic and Test Mode. 9.1. Service Mode Summary Table The service modes can be activated by pressing various button combination on the main unit and remote control unit. Below is the...
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SA-AK750PL Item FL Display Key Operation Mode Name Description Front Key Doctor Mode To enter into Doctor (Display 1) In any mode: Mode for checking of 1. Press [ ] button on main unit various items and follow by [4] and [7] on remote control.
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SA-AK750PL Item FL Display Key Operation Mode Name Description Front Key Tape Eject Test To check on the tape In doctor mode: eject function (For deck 1. Press [0] button on remote control. 1/2) FL Display Test To check In doctor mode:...
SA-AK750PL Note: Microprocessor firmware refers to version number for microprocessor IC located on PANEL P.C.B.. It is subject to change which would be updated accordingly. ROM correction checksum refers to the HEX code that is displayed upon key buttons pressed if an EEPROM is loaded in the unit.
SA-AK750PL 9.4. Error code Table Display Self-Diagnosis Function (refer Section 9.2) provides information on any problems occuring for the unit and its respective components by displaying the error codes. These error code such as U**, H** and F** are stored in memory and held unless it is...
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SA-AK750PL The error code is automatically display after entering into self-diagnostic mode. 9.4.1. Error Code Table for Deck Mechanism Error Code Diagnosis Contents Description of error Automatic FL Display Remarks Mode SW, plunger Normal operation during For deck mechanism unit.
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SA-AK750PL Error Code Diagnosis Contents Description of error Automatic FL Display Remarks HOME Cam gear/gear Cam gear does not move to For CD changer unit (CRS1). assembly abnormal “HOME” position under Press [SINGLE CHANGE] on main unit following conditions for next error.
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SA-AK750PL · Only the first 5 errors will be memorized (in backup memory). The subsequence error shall be ignored and not memorize. For system with EEPROM as memory backup,memory space in EEPROM is neccesary. 2. To display all error code memorized In CRS1 Self-Diagnostic mode, press [SINGLE CHANGE] to display subsequence error code.
SA-AK750PL 10 Assembling and Disassembling 10.1. Caution Special Note: This model uses a new CD changer unit CRS1. In this following section does not contain the necessary disassembly & assembly information for the CD changer unit (CRS1) except the disasembly & assembly of traverse unit. Kindly refer to the original service manual for the CD changer unit.
SA-AK750PL 10.2. Disassembly flow chart The following chart is the procedure for disassembling the casing and inside parts for internal inspection when carrying out the servicing. To assemble the unit, reverse the steps shown in the chart as below.
SA-AK750PL 10.4. Disassembly of Top Cabinet Step 1 Remove 3 screws on both sides on top cabinet. Step 2 Remove 5 screws at the rear. Step 3 Lift the sides of top cabinet outwards. Step 4 Push the top cabinet backwards to release catches.
SA-AK750PL Step 4 Lift the CD changer unit upwards to remove it. · Disassembly of Mecha Chassis Step 5 Remove 2 screws. Step 6 Remove the Mecha Chassis. Note: For disassembly & assembly of traverse unit, please refer to section 10.16 of this service manual.Please refer to original Service Manual for the Disassembly and Assembly of the CD Changer Unit (CRS1).
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SA-AK750PL Step 2 Detach cable CN2810 at Main P.C.B.. Step 3 Detach FFC cables (CN2801 & CN2805) at Main P.C.B.. Step 4 Remove rear panel.
SA-AK750PL 10.9. Disassembly of Power P.C.B. · Follow the (Step 1) - (Step 5) of Item 10.4 · Follow the (Step 1) - (Step 4) of Item 10.5 · Follow the (Step 1) - (Step 4) of Item 10.6 · Follow the (Step 1) - (Step 3) of Item 10.7 Step 1 Remove the 5 screws on Power P.C.B..
SA-AK750PL Step 3 Remove up the heat sink sub assembly (with IC5501). Step 4 Remove screw and IC clip. Step 5 Remove IC5501 from the sub assembly. Caution: During assembly of the heat sink sub assembly (with IC5501) all soldering points is touch-up to avoid dry- joints.
SA-AK750PL Step 5 Remove the front panel unit. Note: Ensure 2 claws located at the bottom chassis is seated into the 2 slots at bottom of front panel at 2 catches (one on each side) of bottom chassis to be aligned to front panel’s slot.
SA-AK750PL Step 3 Remove Deck P.C.B. Step 2 Desolder wire at deck motor terminals. 10.16. Disassembly of Traverse Unit · Follow the (Step 1) - (Step 5) of Item 10.4 · Follow the (Step 1) - (Step 4) of Item 10.5 Important notes: Ensure all the trays are in the “STOCK”...
SA-AK750PL Step 3: Remove the traverse unit as arrow shown. · Assembly of Traverse Unit Step 2: Push the traverse slide plate as arrow shown to lock the traverse unit. Step 1: Turn over the unit and install the traverse unit.
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SA-AK750PL 10.17.1. Replacement of Pinch Roller and Head Block...
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SA-AK750PL 10.17.2. Replacement of Motor, Capstan Belt A, Capstan Belt B, and Winding Belt...
SA-AK750PL 10.19. Disassembly of cassette lid · Follow the (Step 1) - (Step 4) of Item 10.4 · Follow the (Step 1) - (Step 4) of Item 10.5 · Follow the (Step 1) - (Step 5) of Item 10.10 · Follow the (Step 1) - (Step 3) of Item 10.14 Step 1 Lift up the lever upward, open the cassette deck.
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SA-AK750PL Step 2 Push the lever upward and open the cassette lid. Remove the cassette tape. Note: Follow 10.19 Disassembly of cassette lid (Step1) to (Step 3). Remove the cassette tape.
SA-AK750PL 11 Service Fixture and Tools Service Tools Extension FFC (A) Deck P.C.B. - Main P.C.B. REEX0485 (14 Pins) 12 Service Positions Note: For description of the disassembly procedures, see the Section 10. 12.1. Checking and Repairing of Main P.C.B.
SA-AK750PL 13 Procedure for Checking Operation of Individual Parts of Deck Mechanism Unit 13.1. Operation Check with Cassette Tape 1. Pull up the EJECT lever using a rubber band. (Fig. 6) 2. Supply DC5V to MOTOR. (→ MOTOR rotates.) (Fig. 5) 3.
SA-AK750PL 14 Measurement And Adjustments 14.1. Cassette Deck Section 14.1.1. Requirements · Test tape (QZZCFM) (QZZCWAT) · Normal blank cassette tape (QZZCRA) · Digital frequency counter · Oscilloscope · Electrical voltmeter · Headphone jack output jig (Fig 8) 14.1.2. Setting of Unit ·...
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SA-AK750PL Fig. 10 Fig. 11 14.1.5. Bias Voltage Check 1. Connect an electrical voltmeter. (fig 12) (Fig 9 for location of test points) 2. Set the function to “TAPE” position. 3. Insert a normal blank cassette tape (QZZCRA). 4. While pressing and holding down [REC( )] button, press [TAPE( )] button to pause the recording mode.
SA-AK750PL 15 Voltage and Waveform Chart Note: Circuit voltage and waveform described herein shall be regarded as reference information when probing defect point, because it may differ from an actual measuring value due to difference of Measuring instrument and its measuring condition and product itself.
SA-AK750PL 16 Wiring Connection Diagram JK2803 9 ..1 CN3601 H5104 CN2810 TUNER MOTOR PACK CN2809 POWER P.C.B. SOLDER SIDE CN2801 MAIN P.C.B. SOLDER SIDE RIGHT SPEAKERS TO CRS1 JK5101 CN3200 (CN1) LEFT SPEAKERS CN2808 SUBWOOFER...
SWITCH PROCESSOR/ TO MAIN CN7002 CN2801 (1/2) DIGITAL FILTER 3.3V 3.3V 3.3V 3.3V D/A CONVERTER MUTE PC1 4 CN7002 CN2801 [CH1] LCH OUT 3.3V TO MAIN CN7002 CN2801 (2/2) RCH OUT MUTE PC2 2 [CH2] SA-AK750PL CD SERVO BLOCK DIAGRAM...
: AM SIGNAL LINE : FM/AM SIGNAL LINE : USB SIGNAL LINE : FM SIGNAL LINE : AUX SIGNAL LINE : TAPE PLAYBACK SIGNAL : TAPE RECORD SIGNAL LINE ( ) Indicates the Pin No. of Right Channel. SA-AK750PL DECK/DECK MECHANISM BLOCK DIAGRAM...
FROM DECK Q2501 D2503 LM.1 LEVEL METER CONTROL SWITCH ASPDA ASPCLK IDCDET Q2942 FAN MOTOR ON/OFF SWITCH TO FAN D2947 Q2943 FAN SUPPLY FROM POWER CONTROL SWITCH Q2949 Q2948 D2946 DC DETECT DC DETECT SWITCH SWITCH SA-AK750PL MAIN 1/2 DIAGRAM...
Q6502 VR6511 VOLUME TO MAIN (1/2) JK6751 M.PORT S6201-S6207 TO MAIN (2/2) JK6551 HEADPHONE TO MAIN (1/2) SUB PANEL CIRCUIT S6301-S6309 VR6491 +VREF MIC VOLUME +VREF TO MAIN (2/2) S6106-S6109 S6101-S6105 QR6457 MOT10V DRIVE SUB PANEL P.C.B SA-AK750PL PANEL DIAGRAM...
FAN ON/OFF SWITCH SWITCH D5126 TO MAIN (1/2) Q5111 Q5101,Q5110 +15V REGULATOR Q5102 Q5108,Q5109 CURRENT CONTROL SWITCH TO TRANSFORMER Q5112,Q5114 Q5113 CURRENT STABLISER CURRENT LMIITER 11V REGULATOR SWITCH IC5101 TO MAIN C0DAZYY00005 (2/2) REGULATOR IC D5130 5.6V 3.3V SA-AK750PL POWER DIAGRAM CTRL...
SA-AK750PL 18 Notes Of Schematic Diagram (All schematic diagrams may be modified at any time with : Tape Record Signal line the development of new technology) : Tape Playback Signal line Notes: S971: Mode switch. : FM/ AM Signal line S972: Half switch.
SA-AK750PL 19.2. (B) Main Circuit SCHEMATIC DIAGRAM - 2 MAIN CIRCUIT : TAPE PLAYBACK SIGNAL LINE : FM/AM SIGNAL LINE : MAIN SIGNAL LINE : AUX SIGNAL LINE : MIC SIGNAL LINE : +B SIGNAL LINE : CD SIGNAL : TAPE RECORD SIGNAL LINE...
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SA-AK750PL SCHEMATIC DIAGRAM - 4 MAIN CIRCUIT : +B SIGNAL LINE : CD SIGNAL LINE : FM/AM SIGNAL LINE : MAIN SIGNAL LINE : AUX SIGNAL LINE : USB SIGNAL LINE W658 D2811 B0ADCJ000020 R2894 R2121 3.3k TO MAIN SECTION (1/4) C2121 +3.3V...
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W615 Q2937 Q2936 28 27 25 24 21 20 12 11 11 12 13 14 B1ACKD000006 CD SUPPLY CONTROL SWITCH Q2937 B1GBCFJJ0051 CHANGER PLUNGER CN2806 CN2805 ON/OFF SWITCH TO CRSI (CN1) PANEL CIRCUIT (CN6601) IN SCHEMATIC DIAGRAM-6 SA-AK750PL MAIN CIRCUIT...
SA-AK750PL 20.4. (D) Sub Panel P.C.B., & (I) USB P.C.B. (Side A & B) SUB PANEL P.C.B (REPV0131B) USB P.C.B (REPV0101A) JW6001 D6462 (VOL. LED) S6304 S6305 R 6 3 0 2 R 6 3 0 3 ( T U N E R )
SA-AK750PL 22 Terminal Function of IC's 22.1. IC7001 (MN6627954MA) Servo Processor,Digital Signal Processor/Digital filter and D/A Converter Pin No. Mark Function Pin No. Mark Function DRAM address signal O/P 11 IREF Reference I/P DRAM address signal O/P 9 PLLF PLL Loop Filter Terminal (Phase...
SA-AK750PL 22.2. IC7002 (BA5948FPE2) IC 4CH Drive Pin No. Mark Function Pin No. Mark Function Motor Driver 92 Input Motor Drive (3) reverse - action output Turntable Motor Drive Signal (“L”:ON) Motor Drive (3) forward - action output Motor Drive (1) Input...
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SA-AK750PL Pin No. Mark Function /Reset_SW CD Limit Switch Input for the most Inner Point (Active Low) HOME_SW Home Switch for CRS1 CD_RST CD Reset output CLOSE_SW CLOSE switch for CRS1 OPEN_SW Open switch for CRS1 CRS1 motor CW CRS1 motor CCW...
SA-AK750PL 24 Replacement Parts List Notes: · Important safety notice: Components identified by mark have special characteristics important for safety. Furthermore, special parts which have purposes of fire-retardent (resistors), high-quality sound (capacitors), low noise (resistors), etc are used. When replacing any of these components, be sure to use only manufacturer’s specified parts shown in the parts list.
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SA-AK750PL Ref. No. Part No. Part Name & Description Remarks Ref. No. Part No. Part Name & Description Remarks RMC0061 PACK SPRING Q1317 B1ABGC000005 TRANSISTOR RXF0061-1 FLYWHEEL F ASS’Y Q2142 B1ABCF000176 TRANSISTOR RXG0040 FF RELAY GEAR ASS’Y Q2242 B1ABCF000176 TRANSISTOR...
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SA-AK750PL Ref. No. Part No. Part Name & Description Remarks Ref. No. Part No. Part Name & Description Remarks D2946 B0ADCJ000020 DIODE S6105 EVQ21405RJ SW USB D3101 B0EAKM000117 DIODE S6106 EVQ21405RJ SW STOP/-DEMO D5101 B0BA01100004 DIODE S6108 EVQ21405RJ SW H.BASS/ SUBWOOFER...
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SA-AK750PL Ref. No. Part No. Part Name & Description Remarks Ref. No. Part No. Part Name & Description Remarks JK6551 K2HC103A0024 JK HP LB840 J0JAC0000021 CHIP INDUCTOR JK6751 K2HC1YYA0002 JK MUSIC PORT LB841 J0JAC0000021 CHIP INDUCTOR LB843 J0JAC0000021 CHIP INDUCTOR...
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SA-AK750PL Ref. No. Part No. Part Name & Description Remarks Ref. No. Part No. Part Name & Description Remarks W641 ERJ6GEY0R00V CHIP JUMPER W7001 D0GDR00JA017 CHIP JUMPER W642 ERJ6GEY0R00V CHIP JUMPER W7002 D0GDR00JA017 CHIP JUMPER W643 ERJ6GEY0R00V CHIP JUMPER W7003...
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SA-AK750PL Ref. No. Part No. Part Name & Description Remarks Ref. No. Part No. Part Name & Description Remarks R1101 D0GB330JA008 33 1/16W R2196 D0GB103JA008 10K 1/16W R1102 D0GB152JA008 1.5K 1/16W R2202 D0GB152JA008 1.5K 1/16W R1103 D0GB183JA008 18K 1/16W R2203 D0GB222JA041 2.2K 1/16W...
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SA-AK750PL Ref. No. Part No. Part Name & Description Remarks Ref. No. Part No. Part Name & Description Remarks R2445 D0GB152JA008 1.5K 1/16W R2836 D0GB101JA007 100 1/16W R2446 D0GB332JA007 3.3K 1/16W R2837 D0GB101JA007 100 1/16W R2447 D0GB1R0JA007 1 1/16W R2838...
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SA-AK750PL Ref. No. Part No. Part Name & Description Remarks Ref. No. Part No. Part Name & Description Remarks R5107 D0GB561JA007 560 1/16W R5512 D0GB274JA007 270K 1/16W R5108 D0GB470JA008 47 1/16W R5513 D0GB334JA007 330K 1/16W R5109 D0GB102JA008 1K 1/16W R5514...
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SA-AK750PL Ref. No. Part No. Part Name & Description Remarks Ref. No. Part No. Part Name & Description Remarks R6756 D0GB102JA008 1K 1/16W C1201 F2A1H1R0A145 1 50V R6757 D0GB332JA007 3.3K 1/16W C1202 F1H1H471A219 470P 50V R6758 D0GB682JA008 6.8K 1/16W C1203...
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SA-AK750PL Ref. No. Part No. Part Name & Description Remarks Ref. No. Part No. Part Name & Description Remarks C2281 F1H1A105A025 1 10V C2803 F1H1A105A025 1 10V C2282 F1H1A105A025 1 10V C2821 ECJ1VC1H101K 100P 50V C2283 F1H1H473A783 0.047 50V C2853 F1H1C104A041 0.1 16V...
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SA-AK750PL Ref. No. Part No. Part Name & Description Remarks Ref. No. Part No. Part Name & Description Remarks C5201 F1H1H471A219 470P 50V C5432 F1H1H221A748 220P 50V C5202 ECJ1VC1H101K 100P 50V C5433 F1H1H221A748 220P 50V C5203 ECJ1VC1H101K 100P 50V C5434 F1H1H153A219 0.015 50V...