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ORDER NO. MD0005090C3 CD Stereo System SA-AK78 Colour (S)... Silver Type Area (GC)... Asia, Latin America, Africa and Middle Near East TAPE SECTION AR2 MECHANISM SERIES CD SECTION RAE0152Z-3 TRAVERSE DECK SERIES Specification Amplifier Section Input impedance Front speaker power output AUX 1, AUX 2 10 kΩ...
SA-AK78 • • 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.
SA-AK78 5 Handling Precautions For Traverse Deck The laser diode in the traverse deck (optical pickup) may break down due to potential difference caused by static electricity of clothes or human body. So, be careful of electrostatic breakdown during repair of the traverse deck (optical pickup).
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SA-AK78 abgestrahlt. Wellenlänge : 780nm Maximale Strahlungsleistung der Lasereinheit :100W/VDE Die Strahlung an der Lasereinheit ist ungefährlich, wenn folgende Punkte beachtet werden: 1. Die Lasereinheit nicht zerlegen, da die Strahlung an der freigelegten Laserdiode gefährlich ist. 2. Den werkseitig justierten Einstellregler der Lasereinhit nicht verstellen.
SA-AK78 8 Self-Diagnostic Display Function 8.1. Self-diagnostic display This unit is equipped with a self-diagnostic display function which, if a problem occurs, will display an error code corresponding to the problem. Use this function when performing maintenance on the unit.
SA-AK78 10 CD Test Mode Function This CD test mode is provided to check CD unit without connecting to changer loading mechanism. This mode shall operate CD PLAY with CD unit being connected only and CD Automatic Alignment result is shown on FL display.
SA-AK78 11.1.3. Bias and Erase Voltage Check 1. Set the unit to “AUX” position. 2. Insert the Normal blank tape (QZZCRA) into DECK 2 and the unit to “REC” mode (use “ REC/STOP” key). 3. Measure and make sure that the output is within the standard value.
SA-AK78 12 Terminal Function of IC’s 12.1. IC701 (AN8839NSBE2) Servo Amplifier Pin No. Mark Function Pin No. Mark Function Tracking signal input 1 /RFDET NRFDET output (“L” : detection) Tracking signal input 2 PDOWN Power-down input Power supply OFTR OFTR output Focus signal input terminal 1 N.C.
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SA-AK78 Mark Function Mark Function EFM signal output CLVS Spindle servo phase synchronizing signal output PLL extraction clock output ("H" : CLV, "L" : rough servo) (fPCK = 4.321 MHz during normal playback) Sub-code checked output (“H’ :OK, “L” :NG) VCOF2 VCO Loop filter for 33.8688...
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SA-AK78 Mark Function MIC SW MIC detect SW input(L:NO MIC H:MIC) PHONE PHONE detect input (L:NO PHONE H:PHONE) SER7 Serial 7 output (EEPROM IC CS) SER6 Serial 6 output (DSP MPU CS) SER5 Serial 5 output (PLL IC CE) Remote control input...
SA-AK78 13 Block Diagram CD CHANGER SECTION • AN8839NSBE2 (RF) OPTICAL PICKUP IC701 TJ701 SERVO AMP SEMICONDUCTOR RFIN CSBRT LASER OFTR RFENV TENV Q701 DET. Vref. Laser OFTR power Vref. drive DET. /RFDET Vref. /RFDET DET. FE IN Vref. SUBTRACTER...
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SA-AK78 MN662790RSC IC702 SERVO PROCESSOR / DIGITAL SIGNAL PROCESSOR DIGITAL FILTER / D/A CONVERTER 79 80 IOSEL CLVS OUTR BLKCK BLKCK R ch /CLDCK SBCK SUBC OUTL DEMPH SSEL FLAG SQCK SQCK IPFLAG SUBQ SUBQ DIGITAL AUDIO INTERFACE PLLF DIGITAL AUDIO...
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SA-AK78 Note: : CD SIGNAL LINE CD P.B.signal M REQ M CS M CK To MAIN SECTION M SI M SO M RST X451 (8MHz) SW5V /RST MCLK M38503M4254F IC451 MDATA SYSTEM CONTROL SQCK Q451, S701 TC74HCT7007A PLUNGER (REST) DRIVE...
SA-AK78 MAIN SECTION • FM ANT AM ANT +B(FM) RF AMP FM MIXER COIL COIL +B(FM) FM IF +B(FM) BUFFER LOCAL OSC +B(FM) LA1833MN FM / AM I F AMP, DET / AM OSC, MIX / FM MPX DECODER BUFF.
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SA-AK78 To Main section CD P.B.signal M51167AFP-TB Q1153 IC1101 (1/2) (Q1154) P.B. EQ / TPS AMP BUFFER [ DECK 1 ] 36(1) PLAYBACK TP9( TP10 HEAD 33(4) 30(7) (L ch) 32(5) Q1103 (Q1104) [ DECK 2 ] (TP4) 31(6) HEAD SELECT...
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SA-AK78 HEADPHONES R ch RSN311W64A-P IC501 POWER AMP D202 Q503 SWITCHING (REMOTE) D601 POWER CONTROL CIRCUIT HIGH RLY505 (25) SPEAKERS (6 Ω) (22) D503 RLY503 (18) (12) SURROUND SPEAKERS (8 Ω) RLY504 POWER CONTROL/ PROTECTION CIRCUIT Q501,502 OVER Q504 LOAD DET.
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SA-AK78 Notes : CD SIGNAL LINE : FM SIGNAL LINE : FM OSC SIGNAL LINE : AM SIGNAL LINE : AM OSC SIGNAL LINE : TAPE PLAYBACK SIGNAL LINE : TAPE RECORDING SIGNAL LINE STK470-050 : SUB WOOFER/FRONT LOW SP DRIVE SIGNAL LINE...
SA-AK78 14 Schematic Diagram (All schematic diagrams may be modified at any time with Tray open switch the development of new technology) CD offset detect switch Spindle bottom position detect switch Note : • • The voltage value and waveforms are the reference voltage...
SA-AK78 SCHEMATIC DIAGRAM-1 : + B Line : CD Signal Line CD SERVO CIRCUIT OPTICAL PICKUP PLAY CIRCUIT 0.6V C701 6.3V33 R701 C703 0.5us. 0.2V/DIV 6.3V100 Q701 2.7V Q701 3.2V LASER DIODE ((2.3V)) 2SA1037AKSTX C704 CN701 LASER POWER DRIVE 0.9V...
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SA-AK78 SCHEMATIC DIAGRAM-2 : + B Line : CD Signal Line R717 C727 50V1 C725 1000P R721 C726 1000P C728 R718 50V1 C743 PLAY 2.2V CN702 Lch OUT 1KHz, 0dB A.GND C731 C753 Rch OUT 470P 6.3V220 +3.3V D.GND C730...
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SA-AK78 SCHEMATIC DIAGRAM-3 :NEGATIVE VOLTAGE LINE :TAPE PLAYBACK SIGNAL LINE MECHANISM CIRCUIT :POSITIVE VOLTAGE LINE : RECORDING SIGNAL LINE 14.8V R1103 C1193 C1101 1000P 1000P R1102 Q1101 ((0V)) 100K ((4.2V)) 2SJ498CDTA DECK1 HEAD SELECT ((0V)) (REC:ON) L ch CS1101 PLAYBACK...
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SA-AK78 SCHEMATIC DIAGRAM-4 :NEGATIVE VOLTAGE LINE :TAPE PLAYBACK SIGNAL LINE :POSITIVE VOLTAGE LINE : RECORDING SIGNAL LINE 14.8V C1133 50V4.7 Q1107 DTC144TKA146 P.B EQ/ REC EQ (CrO / H.SPEED) R1121 ((4.8V)):CrO ((0V)) ((0V)) C1129 C1131 C1135 C1146 820P 820P 1000P...
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SA-AK78 SCHEMATIC DIAGRAM-5 :NEGATIVE VOLTAGE LINE :TAPE PLAYBACK SIGNAL LINE MECHANISM CIRCUIT :POSITIVE VOLTAGE LINE : RECORDING SIGNAL LINE 14.8V R1106 2.2K Q1151,1152 DTC144TKA146 R1151 C1165 SWITCHING(PLAY:ON) 16V10 ((8.8V)) ((2.6V)) Q1153 0.1V ((0V)) ((3.8V)) Q1151 ((2.1V)) Q1153,1154 2SC2412KT96R MUTING 0.1V ((3.8V))
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SA-AK78 SCHEMATIC DIAGRAM-6 :NEGATIVE VOLTAGE LINE :TAPE PLAYBACK SIGNAL LINE :POSITIVE VOLTAGE LINE : RECORDING SIGNAL LINE 14.8V H1100 M.GND MO.GND MO +B 14.2V MAIN CIRCUIT D.GND R1144 (CN100) +B(3) on SCHEMATIC Rch IN DIAGRAM-12 Lch IN R1143 A.GND Rch OUT...
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SA-AK78 SCHEMATIC DIAGRAM-7 :MIC SIGNAL LINE OPERATION(1) CIRCUIT :POSITIVE VOLTAGE LINE R930 R929 R928 R927 R926 R925 R924 R923 R922 R921 6.8K 4.7K 2.7K 2.2K 1.8K 1.2K H603B H603A Q608 D615-619 2SB621ARSTA SLR325MCT31W POWER SUPPLY 6.8V 6.1V 6.8V R637 FL CIRCUIT...
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SA-AK78 SCHEMATIC DIAGRAM-9 :MIC SIGNAL LINE :POSITIVE VOLTAGE LINE :NEGATIVE VOLTAGE LINE :CD SIGNAL LINE -28.4V FL601(RSL0296-F) FL DISPLAY 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43...
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SA-AK78 SCHEMATIC DIAGRAM-10 :POSITIVE VOLTAGE LINE LOADING MOTOR CIRCUIT TA7291P MOTOR DRIVE 0.01 CLAMP SW (LOADING MOTOR) CIRCUIT MTZJ4R7BTA PLUNGER (CLAMP) (TRAY POSITION 2 DET.) (TRAY POSITION 1 DET.) BOTTOM SW (OPEN DET.) CIRCUIT RVTDTC143EST MOTOR DRIVE (BOTTOM) 4.7K 4.7K...
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SA-AK78 SCHEMATIC DIAGRAM-11 :MIC SIGNAL LINE MAIN CIRCUIT :POSITIVE VOLTAGE LINE :NEGATIVE VOLTAGE LINE :CD SIGNAL LINE R213 JK202 R225 R227 2.7K C201 R229 4.7K 0.01 FRONT C235 R233 4.7K R214 -7.7V R217 JK202 8.2K IC201 NJU7313AMT2 SURROUND INPUT SELECTOR...
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SA-AK78 SCHEMATIC DIAGRAM-12 :POSITIVE VOLTAGE LINE :NEGATIVE VOLTAGE LINE :CD SIGNAL LINE IC453 TC74HCT7007A INTERFACE 4.7V 3.2V C452 0.01 3.2V R471 R467 R489 R473 R474 5.1V R470 1.5K R468 100K R475 R476 R477 C453 0.022 R478 X451 R479 (8MHz) R480 L452 2.1V...
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SA-AK78 SCHEMATIC DIAGRAM-13 :MIC SIGNAL LINE MAIN CIRCUIT :POSITIVE VOLTAGE LINE :NEGATIVE VOLTAGE LINE :CD SIGNAL LINE R406 R440 DOK2 DSP2 DSP1 R420 CNVss EXP11 4.9V RESET EXP12 DRST2 EXP13 P40 NC 2.3V X IN AVss R407 2.4V X OUT...
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SA-AK78 SCHEMATIC DIAGRAM-14 :SUB WOOFER/FRONT LOW SP DRIVE SIGNAL LINE :POSITIVE VOLTAGE LINE :NEGATIVE VOLTAGE LINE :CD SIGNAL LINE :SURROUND/HIGHT SP DRIVE SIGNAL LINE R841 R840 R811 100K R827 4.7K C893 R833 0.022 4.7K CKO1 C810 2.5V TST0 CKO0 L805 2200P 2.5V...
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SA-AK78 SCHEMATIC DIAGRAM-15 :NEGATIVE VOLTAGE LINE :SUB WOOFER/FRONT LOW SP DRIVE SIGNAL LINE MAIN CIRCUIT :POSITIVE VOLTAGE LINE :CD SIGNAL LINE :SURROUND/HIGHT SP DRIVE SIGNAL LINE R890 R861 100K R828 4.7K C895 R883 0.022 4.7K L806 CKO1 C860 TST0 CKO0...
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SA-AK78 SCHEMATIC DIAGRAM-16 :SUB WOOFER/FRONT LOW SP DRIVE SIGNAL LINE :POSITIVE VOLTAGE LINE :NEGATIVE VOLTAGE LINE :CD SIGNAL LINE :SURROUND/HIGHT SP DRIVE SIGNAL LINE C262 R268 R270 50V4.7 3.3K R266 7.7V -5.3V -5.3V -5.3V -5.3V C264 C266 R276 C270 100P 16V10 -5.3V...
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SA-AK78 SCHEMATIC DIAGRAM-17 :NEGATIVE VOLTAGE LINE :SUB WOOFER/FRONT LOW SP DRIVE SIGNAL LINE MAIN CIRCUIT :POSITIVE VOLTAGE LINE :CD SIGNAL LINE :SURROUND/HIGHT SP DRIVE SIGNAL LINE C330 R337 JK204 16V10 SUB WOOFFER R332 C329 C331 16V10 0.01 Q307 2SD2144STA -5.7V MUTING -5.7V...
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SA-AK78 SCHEMATIC DIAGRAM-18 :NEGATIVE VOLTAGE LINE :SUB WOOFER/FRONT LOW SP DRIVE SIGNAL LINE POWER CIRCUIT :POSITIVE VOLTAGE LINE :CD SIGNAL LINE :SURROUND/HIGHT SP DRIVE SIGNAL LINE IC501 RSN311W64A-P POWER AMP(HIGH,MID,LOW) -65V 64.6V -32.1V 31.6V 0V -31.9V 31.4V -65V 64.6V 0V R529 31.6V...
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SA-AK78 SCHEMATIC DIAGRAM-19 :NEGATIVE VOLTAGE LINE :SUB WOOFER/FRONT LOW SP DRIVE SIGNAL LINE :POSITIVE VOLTAGE LINE :CD SIGNAL LINE :SURROUND/HIGHT SP DRIVE SIGNAL LINE IC502 RSN35H1 POWER AMP(CENTER) JK501 RLY504 HIGHT MUTE LATCH -15.3V -4.2V -15V -32.1V 31.6V 0V R545...
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SA-AK78 SCHEMATIC DIAGRAM-20 :NEGATIVE VOLTAGE LINE :POSITIVE VOLTAGE LINE AC TRANS CIRCUIT CN501 SYNC FL CIRCUIT(H602) on SCHEMATIC DIAGRAM-9 / ECO SYS5.8V 5.8V Q593 KTC3199GRTA REGULATOR 5.8V 10.4V 6.4V D597 R596 RVD1SS133TA 820K SUB-TRANS CIRCUIT C593 Q592 16V1000 2SC3940AQSTA REGULATOR...
SA-AK78 18 Parts Location and 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.
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SA-AK78 18.1. Mecanismo do Deck Montado: RD-JMD034-Z 18.1.1. Deck Mechanism Parts Location...
SA-AK78 18.1.2. Deck Mechanism Parts List Ref. Part No. Part Name & Description Remarks RMM0131 BRAKE ROD Ref. Part No. Part Name & Description Remarks RMM0133-1 EJECT ROD RMQ0519 REEL HUB CASSETTE DECK RMS0398-1 MOVING CORE RSJ0003 PLUNGER RED0050 R/P HEAD BLOCK UNIT...
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SA-AK78 18.2. CD Loading Mechanism (RD-DAC024-Z) 18.2.1. CD Loading Mechanism Parts Location...
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SA-AK78 Ref. Part No. Part Name & Description Remarks 18.2.2. CD Mechanism Parts List RMX0140 DISC SPACER Ref. Part No. Part Name & Description Remarks RME0261 FRONT LOCK SPRING RMQ0742 SPINDLE BASE TRAVERSE DECK RML0517 TIMING LEVER RML0516 PLUNGER LEVER...
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SA-AK78 18.3. Cabinet 18.3.1. Cabinet Parts Location...
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SA-AK78 Ref. Part No. Part Name & Description Remarks Ref. Part No. Part Name & Description Remarks Q384 2SC2412KT96R TRANSISTOR D386 UDZSTE175R1B DIODE Q385 DTA114EKA146 TRANSISTOR D451 RL1N4003N02 DIODE Q451 2SB621ARSTA TRANSISTOR D453 RL1N4003N02 DIODE Q452 DTC114YKA146 TRANSISTOR D454 RL1N4003N02...
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SA-AK78 Ref. Part No. Part Name & Description Remarks Ref. Part No. Part Name & Description Remarks D658 MTZJ4R7BTA DIODE S953 RSH1A019-2U SW LEAF D665 RVD1SS133TA DIODE S971 RSH1A018-3U LEAF SWITCH D666 RVD1SS133TA DIODE S972 RSH1A019-2U SW LEAF D668 RVD1SS133TA...
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SA-AK78 Ref. Part No. Part Name & Description Remarks Ref. Part No. Part Name & Description Remarks W500 REXX0206 STANDBY BY WIRE COMPONENT COMBINATION W502 REX1003 12P WIRE UNIT W506 REX1004 10P WIRE UNIT Z501 ERZV10V511CS W601 RWJ0208155RX 8P PANEL TO DECK...
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SA-AK78 Ref. Part No. Part Name & Description Remarks Ref. Part No. Part Name & Description Remarks R258 ERJ6GEYJ102V 1K 1/10W R358 ERJ6GEYJ563V 56K 1/10W R259 ERJ6GEYJ103V 10K 1/10W R359 ERDS1FVJ180T 18 1/2W R260 ERJ6GEYJ103V 10K 1/10W R360 ERJ6GEYJ472V 4.7K 1/10W...
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SA-AK78 Ref. Part No. Part Name & Description Remarks Ref. Part No. Part Name & Description Remarks R459 ERJ6GEYJ272V 2.7K 1/10W R550 ERDS2TJ563T 56K 1/4W R460 ERJ6GEYJ272V 2.7K 1/10W R551 ERDS2TJ334T 330K 1/4W R462 ERJ6GEYJ103V 10K 1/10W R552 ERDS2TJ223T 22K 1/4W...
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SA-AK78 Ref. Part No. Part Name & Description Remarks Ref. Part No. Part Name & Description Remarks R627 ERDS2TJ222T 2.2K 1/4W R727 ERJ6GEYJ392A 3.9K 1/10W R628 ERDS2TJ272T 2.7K 1/4W R728 ERJ6GEYJ392A 3.9K 1/10W R629 ERDS2TJ473T 47K 1/4W R729 ERJ6GEYJ392A 3.9K 1/10W...
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SA-AK78 Ref. Part No. Part Name & Description Remarks Ref. Part No. Part Name & Description Remarks R865 ERJ6GEYJ222V 2.2K 1/10W R961 ERDS2TJ102T 1K 1/4W R866 ERJ6GEYJ223V 22K 1/10W R962 ERDS2TJ122T 1.2K 1/4W R867 ERJ6GEYJ561V 560 1/10W R963 ERDS2TJ182T 1.8K 1/4W...
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SA-AK78 Ref. Part No. Part Name & Description Remarks Ref. Part No. Part Name & Description Remarks R1167 ERJ6GEYJ470A 47 1/10W C267 ECUV1H102KBN 1000P 50V R1170 ERJ6GEYJ102A 1K 1/10W C268 ECUV1H102KBN 1000P 50V R1172 ERJ6GEYJ331A 330 1/10W C269 ECEA1CKA100B 10 16V...
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SA-AK78 Ref. Part No. Part Name & Description Remarks Ref. Part No. Part Name & Description Remarks C506 ECBT1H471KB5 470P 50V C614 ECEA1HKA2R2B 2.2 50V C507 ECBT1H180JC5 18P 50V C615 ECBT1H150JC5 15P 50V C508 ECBT1H180JC5 18P 50V C616 ECBT1H180JC5 18P 50V...
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SA-AK78 Ref. Part No. Part Name & Description Remarks Ref. Part No. Part Name & Description Remarks C732 ECEA0JKA221I 220 6.3V C856 ECEA1HKAR47B 0.47 50V C733 ECUZ1E104MBN 0.1 25V C857 ECUVNE104KBN 0.1 25V C734 ECEA1AKA221I 220 10V C858 ECUVNE104KBN 0.1 25V...
6Ω Specifications are subject to change without notice. 6Ω Weight and dimensions are approximate. 6Ω System : SC-AK78 (GC) Music Center : SA-AK78 (GC) Input power Front Speaker : SB-AK78 (GC) HIGH 60W (Music) Center Speaker : SB-PC70 (GC) 60W (Music)
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SB-AK78 1 Connection of the Speaker Cables • Be sure to connect speaker cables before connecting the AC power supply cord. • The load impedance of any speaker used with this unit must be 6Ω. • Be sure to connect the cable from the right speaker to the roght terminal and the cable from the left speaker to the left terminal.
SB-AK78 3 Cabinet Parts Location Ref. No. Part No. Part Name & Description Remarks 4 Replacement Parts List RGQ0230-K CORD CLIPPER RMQ0941 BUSH TERMINAL Notes : RKA0072-KJ • Important safety notice : RMQ0938 PORT PACKING RYQ0296-S FRONT PANEL (L) Components identified mark have...
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SB-AK78 Ref. No. Part No. Part Name & Description Remarks XTB3+10G SCREW (EXTEND PORT) RGK0985B-H ORNAMENT CAP RKA0072-KJ RGQ0260-S PANEL SPACER RYQ0297-H ORNAMENT ASS’Y (L) RYQ0297A-H ORNAMENT ASS’Y (R) RGK0500-K DUST CAP RMR1208-K TWEETER SPACER REE0981 WIRE RMQ0931C CAB PACKING RMQ0931LK CABINET PACKING CAPACITORS...