ORDER NO. MD0704056CE CD Stereo System SA-AK250GCP Colour (S)... Silver 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 Sensitivity 100 mV, 4.7 kΩ...
SA-AK250GCP (1) CD-Audio (CD-DA) Power supply (2) CD-R/RW (CD-DA, MP3* formatted disc) AC 110 to 127/220 to 240 V, 50/60Hz (3) MP3* Power consumption 95 W *MPEG-1 Layer 3, MPEG-2 Layer 3 Power consumption in standby 0.7 W (Approx.) mode...
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SA-AK250GCP 14 Measurement And Adjustments 19.5. (E) Power Circuit 14.1. Cassette Deck Section 19.6. (F) Deck Circuit 15 Voltage and Waveform Chart 19.7. (H) Transformer Circuit 15.1. CD Servo P.C.B. 20 Printed Circuit Board 15.2. Deck P.C.B. & Deck Mechanism P.C.B.
SA-AK250GCP 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-AK250GCP · 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-AK250GCP Caution Be sure no power is applied to the chassis or circuit, and observe all other safety precautions. 8. Minimize body motions when handling unpackaged replacement ES 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 (ESD) sufficient to...
SA-AK250GCP 3 Handling Precautions For Traverse Unit The laser diode in the traverse unit (with 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 unit (with optical pickup).
SA-AK250GCP 4 Precaution of Laser Diode Caution : This product utilizes a laser diode with the unit turned "ON", invisible laser radiation is emitted from the pick up lens. Wavelength : 780 nm Maximum output radiation power from pick up : 100 µW/VDE Laser radiation from pick up unit is safety level, but be sure the followings: 1.
SA-AK250GCP 5 About Lead Free Solder (PbF) 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-AK250GCP 6 Accessories Note: Refer to “Replacement Parts List” (Section 24) for part number. Remote Control FM Antenna Wire AC Cord AM Loop Antenna Power Plug Adapter...
SA-AK250GCP 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-AK250GCP 9.2.1. EEPROM Checksum (ROM Correction) Purpose: To check for microprocessor firmware version and EEPROM checksum (ROM correction).
SA-AK250GCP Below are the procedures for this mode. Step 1: Enter into Doctor mode (for more information, refer to section 9.2 on the key operation to enter into this mode. Step 2: Check for firmware version and EEPROM checksum (By pressing STOP button on main unit followed by “4” and “7” on remote control).
SA-AK250GCP 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 cleared.
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SA-AK250GCP 9.4.2. Error Code Table For CD Changer Block...
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SA-AK250GCP 9.4.3. Error Code Table For Power Supply 9.4.4. CRS1 Error Code display CRS1 Error Code display 1. The errors that occured in CRS1 Mechanism can be recalled and displayed, in the order of the occurence under self-diagnostic for procedures to enter this mode.
SA-AK250GCP 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-AK250GCP 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-AK250GCP 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-AK250GCP Step 4 Lift the CD changer unit upwards to remove it. Step 5 Remove 2 screws. · Disassembly of Mecha Chassis Step 6 Remove the Mecha Chassis. Note: For disassembly & assembly of traverse unit, please refer to section 10.15 of this service manual. Please refer to original Service Manual for the Disassembly and Assembly of the CD Changer Unit (CRS1).
SA-AK250GCP 10.7. Disassembly of Main 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 Step 1 Detach FFC cables at connectors (CN2803 & CN2806) on Main P.C.B..
SA-AK250GCP 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 Flip the Power P.C.B.
SA-AK250GCP Step 4 Release 2 claws outwards. Step 3 Bent the front panel unit slightly forward as arrow shown. 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-AK250GCP Step 1 Remove 2 screws. Step 2 Desolder wire at deck motor terminals. Step 3 Remove Deck P.C.B. 10.15. 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-AK250GCP 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-AK250GCP 10.16.1. Replacement of Pinch Roller and Head Block...
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SA-AK250GCP 10.16.2. Replacement of Motor, Capstan Belt A, Capstan Belt B, and Winding Belt...
SA-AK250GCP 10.18. 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 10.13 Step 1 Open the cassette lid.
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SA-AK250GCP Note: Follow 10.18 Disassembly of cassette lid (Step1) to (Step 3). Remove the cassette tape.
SA-AK250GCP 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-AK250GCP 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-AK250GCP 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-AK250GCP 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-AK250GCP 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-AK250GCP 16 Wiring Connection Diagram JK2803 9 ..1 CN3601 H5104 CN2810 TO TUNER PACK MOTOR CN2809 CN2801 POWER P.C.B. MAIN P.C.B. SOLDER SIDE SOLDER SIDE RIGHT SPEAKER TO CRS1 JK5103 (CN1) LEFT SPEAKER CN2808 CN2805 CN5103 1 .
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-AK250GCP CD SERVO BLOCK DIAGRAM...
SWITCH Q2511 QR2501, QR2502 SWITCH MUTE MUTEA MUTEA SWITCH DRIVER FROM DECK ASPDA ASPCLK IDCDET Q2942 FAN MOTOR ON/OFF SWITCH TO FAN Q2943 FAN SUPPLY CONTROL SWITCH Q2949 Q2948 D2946 DC DETECT DC DETECT SWITCH SWITCH SA-AK250GCP MAIN 1/2 DIAGRAM...
REMOTE SENSOR JK6501 Q6501 Q6502 TO MAIN (1/2) JK6751 MUSIC 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,S6108 S6101-S6104 SUB PANEL P.C.B SA-AK250GCP 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-AK250GCP POWER DIAGRAM CTRL...
: AM SIGNAL LINE : FM/AM/XM SIGNAL LINE : VIDOE SIGNAL LINE : FM SIGNAL LINE : AUX/IPOD SIGNAL LINE ) Indicates the Pin No. of Right Channel. NOTE : Signal Lines are applicable to the Left Channel only. SA-AK250GCP TRANSFORMER DIAGRAM...
SA-AK250GCP 18 Notes Of Schematic Diagram (All schematic diagrams may be modified at any time with : Main Signal line the development of new technology) : FM/AM Signal line Notes: S971: Mode switch. : Tape Record Signal line S972: Half switch.
SA-AK250GCP 19.2. (B) Main Circuit SCHEMATIC DIAGRAM - 2 MAIN CIRCUIT : +B SIGNAL LINE : CD SIGNAL : TAPE RECORD SIGNAL LINE : TAPE PLAYBACK SIGNAL LINE : FM/AM SIGNAL LINE : MAIN SIGNAL LINE : AUX SIGNAL LINE...
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SA-AK250GCP SCHEMATIC DIAGRAM - 4 MAIN CIRCUIT : +B SIGNAL LINE : CD SIGNAL LINE : FM/AM SIGNAL LINE : MAIN SIGNAL LINE : AUX SIGNAL LINE : USB SIGNAL LINE W617 R2284 D2811 W658 B0ADCJ000020 R2285 R2894 3.3k R2121...
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Q2937 D2937 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-AK250GCP MAIN CIRCUIT...
SA-AK250GCP 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...
SA-AK250GCP 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-AK250GCP 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-AK250GCP 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-AK250GCP Ref. No. Part No. Part Name & Description Remarks Ref. No. Part No. Part Name & Description Remarks 133-2 RMM0132-1 FR ROD Q2937 B1GBCFJJ0051 TRANSISTOR REM0120 CAP MOTOR ASS’Y Q2942 B1ACKD000006 TRANSISTOR RHD26022-1 MOTOR SCREW Q2943 B1ABCF000176 TRANSISTOR XTW2+5LFJ...
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SA-AK250GCP Ref. No. Part No. Part Name & Description Remarks Ref. No. Part No. Part Name & Description Remarks D5154 B0JAME000119 DIODE CN3601 K1KA10AA0031 10P CONNECTOR D5155 B0JAME000119 DIODE CN5102 K1KA12AA0031 12P CONNECTOR D5156 B0JAME000119 DIODE CN5103 K1KA12AA0031 12P CONNECTOR...
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SA-AK250GCP Ref. No. Part No. Part Name & Description Remarks Ref. No. Part No. Part Name & Description Remarks HOLDERS W629 ERJ3GEY0R00V CHIP JUMPER W630 ERJ6GEY0R00V CHIP JUMPER H5104 K1YF09000001 9P WIRE HOLDER W631 ERJ6GEY0R00V CHIP JUMPER H6555 K1YZ09000002 CABLE HOLDER...
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SA-AK250GCP Ref. No. Part No. Part Name & Description Remarks Ref. No. Part No. Part Name & Description Remarks W913 ERJ6GEY0R00V CHIP JUMPER R972 ERDS2TJ821T 820 1/4W W914 ERJ6GEY0R00V CHIP JUMPER R973 ERDS2TJ393T 39K 1/4W W915 ERJ6GEY0R00V CHIP JUMPER R1061...
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SA-AK250GCP Ref. No. Part No. Part Name & Description Remarks Ref. No. Part No. Part Name & Description Remarks R2183 D0GB222JA008 2.2K 1/16W R2452 D0GB180JA008 18 1/16W R2193 D0GB472JA041 4.7K 1/16W R2453 D0GBR00JA008 0 1/16W R2194 D0GB104JA007 100K 1/16W R2454...
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SA-AK250GCP Ref. No. Part No. Part Name & Description Remarks Ref. No. Part No. Part Name & Description Remarks R2916 D0GB472JA008 4.7K 1/16W R5206 D0GB105JA007 1M 1/16W R2918 D0GB102JA008 1K 1/16W R5207 D0GB682JA008 6.8K 1/16W R2921 D0GB472JA041 4.7K 1/16W R5209...
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SA-AK250GCP Ref. No. Part No. Part Name & Description Remarks Ref. No. Part No. Part Name & Description Remarks R6509 D0GB101JA007 100 1/16W C1304 F2A1H4R7A014 4.7 50V R6601 D0GB471JA041 470 1/16W C1305 F2A1C330A234 33 16V R6602 D0GB471JA041 470 1/16W C1307...
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SA-AK250GCP Ref. No. Part No. Part Name & Description Remarks Ref. No. Part No. Part Name & Description Remarks C2343 ECJ1VB1A474K 0.47 10V C3706 F1H1H470A230 47P 50V C2344 ECJ1VB1A474K 0.47 10V C3707 F1H1H470A230 47P 50V C2401 F1H1A224A007 0.22 10V C3708...
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SA-AK250GCP Ref. No. Part No. Part Name & Description Remarks Ref. No. Part No. Part Name & Description Remarks C5331 F1H2A221A009 220P 100V C7218 ECJ1VB1C823K 0.082 16V C5332 F1H2A221A009 220P 100V C7223 F2A1H4R70037 4.7 50V C5333 F1H2A221A009 220P 100V C7225...