Sharp SM-SX1 Service Manual
Sharp SM-SX1 Service Manual

Sharp SM-SX1 Service Manual

1-bit amplifier
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SACD
DIGITAL1 DIGITAL2
LINE1
LINE2
IMPORTANT SERVICE NOTES (SM-SX1 FOR U.S.A. ONLY) ......................................................................................... 2
AC POWER SUPPLY CORD (SM-SX1W ONLY) ............................................................................................................... 2
SPECIFICATIONS ............................................................................................................................................................. 3
NAMES OF PARTS ........................................................................................................................................................... 3
OPERATION MANUAL ....................................................................................................................................................... 5
DISASSEMBLY .................................................................................................................................................................. 6
ADJUSTMENT ................................................................................................................................................................... 8
WIRING PROCESS DIAGRAM ....................................................................................................................................... 10
BLOCK DIAGRAM ........................................................................................................................................................... 12
SCHEMATIC DIAGRAM / WIRING SIDE OF P.W.BOARD .............................................................................................. 14
NOTES ON SCHEMATIC DIAGRAM .............................................................................................................................. 32
TYPES OF TRANSISTOR AND DIODE .......................................................................................................................... 32
WAVEFORMS OF CD CIRCUIT ...................................................................................................................................... 33
TROUBLESHOOTING ..................................................................................................................................................... 34
FUNCTION TABLE OF IC ................................................................................................................................................ 37
SERVICE MANUAL
MODEL
CONTENTS
SHARP CORPORATION
- 1 -
1-BIT AMPLIFIER
SM-SX1
MODEL
1-BIT AMPLIFIER
SM-SX1W
• In the interests of user-safety the set should be restored to its
original condition and only parts identical to those specified be
used.
This document has been published to be used
for after sales service only.
The contents are subject to change without notice.
SM-SX1/SX1W
No. S7063SMSX1///
Page

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Summary of Contents for Sharp SM-SX1

  • Page 1: Table Of Contents

    CONTENTS Page IMPORTANT SERVICE NOTES (SM-SX1 FOR U.S.A. ONLY) ..................2 AC POWER SUPPLY CORD (SM-SX1W ONLY) ....................... 2 SPECIFICATIONS ................................3 NAMES OF PARTS ................................3 OPERATION MANUAL ............................... 5 DISASSEMBLY ..................................
  • Page 2: Important Service Notes (Sm-Sx1 For U.s.a. Only)

    SM-SX1/SX1W FOR A COMPLETE DESCRIPTION OF THE OPERATION OF THIS UNIT, PLEASE REFER TO THE OPERATION MANUAL. IMPORTANT SERVICE NOTES (FOR U.S.A. ONLY) BEFORE RETURNING THE AUDIO PRODUCT (Fire & Shock Hazard) Before returning the audio product to the user, perform the following safety checks.
  • Page 3: Specifications

    SM-SX1/SX1W SPECIFICATIONS Output terminals: Rated output power: DIGITAL OUT; Square type optical RMS; 50 W + 50 W (DIN 45 500) LINE OUT; RCA analog Total harmonic distortion: Speakers; 8 ohms 0.05 % (1 kHz, 1 W) Power source: Frequency response:...
  • Page 4 SM-SX1/SX1W – 4 –...
  • Page 5: Operation Manual

    SM-SX1/SX1W OPERATION MANUAL – 5 –...
  • Page 6: Disassembly

    SM-SX1/SX1W DISASSEMBLY Caution on Disassembly Top Panel Front Panel Follow the below-mentioned notes when disassembling (B1)x3 the unit and reassembling it, to keep it safe and ensure (A1)x5 ø3x8mm excellent performance: ø4x6mm 1. Be sure to remove the power supply plug from the wall outlet before starting to disassemble the unit.
  • Page 7 SM-SX1/SX1W Power PWB AC Input (F4)x1 Push Filter PWB Pull Front Bracket AC Input 1 Bit Amp PWB Filter PWB (M1)x1 Power Knob ø3x6mm (L3)x2 (M2)x3 (L1)x8 (N1)x1 (F3)x2 ø3x8mm ø3 x6mm ø3x6mm (L2)x2 Washer ø3x6mm Input Source (F2)x1 (F3)x2 ø3x6mm...
  • Page 8: Adjustment

    SM-SX1/SX1W ADJUSTMENT Measure the noise distribution between the set output terminals (Lch+, Lch- and Rch+, Rch-), and adjust VRA1 to VRA4. The VRA adjustment sequence is the same as that of the offset voltage adjustment. Measuring instrument: Yokokawa Electric brand SA2400 Measurement range : Refer to Fig.
  • Page 9 SM-SX1/SX1W AC/DC switching power supply, Output voltage adjustment Output Output Connector Connector -22V Side +22V Side semifixed VOL semifixed VOL Check that the AC/DC output voltage is ±22V ±0.15V at the From Main PWB connector. (If different, adjust the voltage using the semifixed VOL as described above.)
  • Page 10: Wiring Process Diagram

    SM-SX1/SX1W (1 BIT PWB) Figure 10-1 WIRING PROCESS DIAGRAM Core mounting position F i g - A Push in the core. Place the core near the connector. Nylon band Fix the core to the aperture using nylon band. (Head inside)
  • Page 11 SM-SX1/SX1W After passing through the cores, insert the terminals in the 4P and 6P housings. Core To avoid unnecessary radiation, attach felt to each lead wire and fix it to the case in order that the lead wires do not overlap each other (to prevent the contact of each lead wire).
  • Page 12: Block Diagram

    SM-SX1/SX1W DIGITAL SIGNAL RLY101 ANALOG SIGNAL SACD J101 Q101 DIGITAL/ANALOG CHANGE VOL301 RLY102 DIGITAL/ANALOG LINE1 RLY301, MAIN CHANGE RLY302 VOLUME RLY802 Q102 Q803 Q301 Q302 RLY103 LINE2 Q103 J102 LINE IC801 IC800 SAMPLING DIGITAL IC102 RATE INTERFACE INVERTER CONVERTER J103...
  • Page 13 IC306 RELAY/SW/ NJM431U MICROCOMPUTER F501 SM-SX1; 4A/125V SW501 SM-SX1W; T3.15A L 250V POWER IC304 OP AMP. +10V LINE NJM78M12 FILTER SOC501 AC INLET IC304 SM-SX1; AC120V, 60Hz +10V NJM78M12 SM-SX1W; AC110-127/ 220-240V,50/60Hz Figure 13 BLOCK DIAGRAM (2/2) – 13 –...
  • Page 14: Schematic Diagram / Wiring Side Of P.w.board

    SM-SX1/SX1W P18 1-C TO 1BIT AMP. TO 1B CNWAM2A CNWA CNP303 CNP304 MAIN PWB-A1 VOL301 MAIN VOLUME RLY301 RLY302 D302 DAN202K D301 DAN202K Q301 R304 2SC2412KR R305 R306 R301 R360 R362 IC308 R374 R363 C349 Q313 220P OPA2134 2SA1036KR C350 R361 ANALOG AMP.
  • Page 15 SM-SX1/SX1W P18 1-C P18 1-A P19 12-C P19 12-A TO 1BIT AMP. TO 1BIT AMP. TO 1BIT AMP. TO 1BIT AMP. CNWAM2A CNWAM1A CNWAM3A CNSA4 CNP303 CNP306 CNP304 CNP305 R307 RLY303 +24V L301 220µH L302 220µH L303 220µH D303 Q303...
  • Page 16: Sampling Rate

    SM-SX1/SX1W IC810:PC CONTROLL IC810 C815 TC7WU04F C801 C816 47/10 X800 11.2896MHz 22 21 20 19 18 17 16 15 14 13 12 44 43 42 41 40 39 38 35 34 37 36 C802 R821 C846 RSTN RSTN SKSY R801...
  • Page 17 SM-SX1/SX1W TROLL DIGITAL PWB-A2 44 43 42 41 40 39 38 37 36 35 34 D800 BCKI RSTN DAN202K BCKI RSTN R845 IC801 LRCI TST2N SM5844AF ICLK TST1N SAMPLING RATE ICKSL STATE C840 4.7/25 CONVERTER IFM1 IISN IISN IFM1 IFM2...
  • Page 18 SM-SX1/SX1W ICA1 1BIT AMP.PWB-B IX2815AF 7Th ORDER MODULATION CONVERSION LSI CA86 RA70 CNWAM1 CNPA2 ANALOG IN R-CH TEST RA86 DGND_AD 100K NFR1(+) GNDX AGND AGND_AD TO MAIN PWB CNWAM1B P15 8-A NFR2(-) ANALOG IN L-CH CNPA1 AGND GNDA AGND_AD AGND_AD RA94 6.8K...
  • Page 19 SM-SX1/SX1W ATION ICA2 74AC00F CXA1 CNPA5 11.2896MHz BLA1 NAND GATE CA21 +5VA 0.22 CA13 BLA2 100/10 AGND CA10 DGND_AD 0.22 AGND_AD BLA3 BLA6 DGND CNP305 CA14 DGND_AD 100/10 BLA5 +5VD MAIN PWB CA12 P15 9-A BLA4 0.22 DGND_AD R(+) RESET...
  • Page 20 SM-SX1/SX1W RX101 TX101 DIGITAL2 DIGITAL J103 DIGITAL1 3 2 1 3 2 1 INPUT SOURCE PWB-A4 L101 C112 R126 ZD101 0.01 MTZJ5.1B L124 RLY101 R117 L117 C101 R101 0.001 R116 J101 4.7K C122 chassis ground 560K LINE2/ 0.022 R102 SACD...
  • Page 21 SM-SX1/SX1W FROM 1BIT AMP. PWB P19 12-F R204 Q201 2.2K SPEAKER 2SC2412KR Q202 RLY201 IC102 TERMINAL 2SA1037KR TP68 74HC153AF R203 TP69 INVERTER R126 R205 SP OUT R-CH R202 D203 R201 100K DN202K 4.7K TP70 TP71 SP OUT L-CH RLY202 D204...
  • Page 22 TP50 UNT502 DATA_OUT TP51 DATA_IN TP52 AC/DC CONVERTER CNP302B MAIN PWB OUTPUT –22V P15 12-H SOC501 F501 AC SOCKET SM-SX1; 4A/125V SM-SX1; AC120V,60Hz SM-SX1W; T3.15A L 250V SM-SX1W; AC110-127/ TP963 220-240V, 50/60Hz SW501 L501 CNS501 C503 POWER TP960 (BROWN) 0.0022...
  • Page 23 SM-SX1/SX1W LED905 LED906 LED907 GL9BC030 GL9BC030 GL9BC030 C909 R915 47/10 R916 C900 10 11 12 13 14 15 16 17 18 10 11 12 13 14 15 16 17 18 IC904 BU2114F LED DRIVER LATCH SOUT ENT PWB-A5 BI901 8 7 6 5 4 3 2 1...
  • Page 24 SM-SX1/SX1W R326 R325 R324 R323 CNS302C CNS302A CNP302 CK17 CK52 CNS302B C318 D303 P28 6 - C R309 CNSA4 C303 R308 TO 1 BIT AMP. Q303 R315 IC303 3 2 1 C311 R393 R317 R314 D306 R318 C312 Q305 Q309...
  • Page 25 SM-SX1/SX1W UNT502 UNT501 R341 R362 Q314 R380 R379 R377 C351 Q320 R351 Q316 R381 R349 R375 R369 R378 R376 COLOR TABLE D322 R371 IC308 C354 R372 C339 C338 R367 R370 R373 R368 BROWN Q318 C353 Q317 Q313 IC307 C347 R359...
  • Page 26 C122 R117 J103 TP28 J103 L120 P30 4 - G DIGITAL 1 IN R120 TP27 D800 CNP904 C808 TP149 R121 C130,C131 SM-SX1 ONLY R845 C120 MICROCOMPUTER L123 TP126 TO TERMINAL C815 C129 PANEL CNS904 TP136 C131 R813 TO TERMINAL SOC101...
  • Page 27 SM-SX1/SX1W R-CH C841 Q201 R205 R204 R203 R201 SPEAKER TERMINAL L-CH C836 IC805 SPEAKER RELAY IC804 PWB-A3(BOTTOM) L804 R861 R863 IC806 IC101 R862 IC807 IC802 IC103 L121 L117 COLOR TABLE IC102 IC801 BROWN RD(R) ORANGE YELLOW X800 GREEN BLUE VIOLET...
  • Page 28 SM-SX1/SX1W CNWAM2A CORE3 CORE2 CORE1 P24 4 - F CNP303 TO MAIN PWB P24 4 - F CNP304 TO MAIN PWB CNWAM1A 3 2 1 3 2 1 1BIT PWB-B (TOP) ZDA84B ZDA83A ZDA81A ZDA82B ZDA84A ZDA83B ZDA82A ZDA81B CNPA3...
  • Page 29 SM-SX1/SX1W : Through-hole where the top and bottom patterns are connected. : Through-hole where the top, bottom and +B patterns are connected. : Through-hole where the top, bottom and ground patterns are connected. 1BIT PWB-B (BOTTOM) CA14 CA13 ICA1 VRA2...
  • Page 30 UNT1 CNWS505 CNWS504 POWER PWB-A9 TP963 SW501 CNWS502 POWER SW501 CNWS503 CNS901 SEGMENT PWB-A5(TOP) C909 C900 TP904 SOC501 SM-SX1; AC120V, 60Hz TP905 SM-SX1W; AC110-127/220-240V,50/60Hz AC INPUT CNP502 C531 R942 TP961 C904 C908 L501 Put The Plastic CORE1 C503 R966 R962 Inner Tube.
  • Page 31 SM-SX1/SX1W IC903 IC905 R968 R970 R969 R967 SEGMENT PWB-A5(BOTTOM) AC INPUT FILTER PWB-A6(BOTTOM) L901 L903 L902 C906 C907 C905 COLOR TABLE BROWN RD (R ) ORANGE R950 R940 R946 YELLOW R974 R937 R936 GREEN IC907 R929 R926 BLUE R925 R924...
  • Page 32: Notes On Schematic Diagram

    SM-SX1/SX1W NOTES ON SCHEMATIC DIAGRAM • Resistor: • The indicated voltage in each section is the one measured To differentiate the units of resistors, such symbol as K and by Digital Multimeter between such a section and the chas- M are used: the symbol K means 1000 ohm and the symbol sis with no signal given.
  • Page 33: Waveforms Of Cd Circuit

    SM-SX1/SX1W WAVEFORMS OF 1 BIT AMP. CIRCUIT • OUTR(+), OUTR(-) • QA1, QA5 • OUTL(+), OUTL(-) • QA2, QA6 • QA3, QA7 Observe • QA4, QA8 each pair. OUTR(+), Observe (OUTL(+)) each pair. (QA2, 3, 4) COLECTOR OUTR(-), (OUTL(-)) (QA6, 7, 8)
  • Page 34: Troubleshooting

    SM-SX1/SX1W TROUBLESHOOTING (LED904 does not come on and it does not sound.) • Power is not supplied. • Check the fuse F501. Does AC100V stand between Pins 1 and 2 of the power • Check the parts on the power filter PWB.
  • Page 35 SM-SX1/SX1W • No sound at the analog input (Line 1 and Line 2) alone. Check the wiring from the input terminal to CNP116 and Is any signal input to CNP116 or CNP117? CNP117. No sound on both Line 1 and Line 2? Check the wiring from RLY101, RLY102, RLY103 and the relays to the microcomputer IC907.
  • Page 36 SM-SX1/SX1W Cont. from page 35 Is any 1-bit signal from Pins 27 and 33 of IC803 output Check IC808, IC809, IC811, IC812 and IC813. to RLY801? Does RLY800 and RLY801 operate? Check the operation of Q801 and Q802 and the wiring of each to the microcomputer IC907.
  • Page 37: Function Table Of Ic

    SM-SX1/SX1W FUNCTION TABLE OF IC IC800 VHiYM3436D/-1: Digital Interface Receiver (YM3436D) • Outline YM3436D(DIR2) is a LSI which receives and demodulates the digital/audio/interface/format signals which comply with EIAJ CP- 340 and AES/EBU. Keeping the features of the existing YM3623B(DIR), it is designed to not only strengthen the external synchronization, error process and other functions but also be more general for the channel status, user data output and other general applications.
  • Page 38 SM-SX1/SX1W IC800 VHiYM3436D/-1: Digital Interface Receiver (YM3436D) 25 28 MCA,MCB,MCC, EXTW WC,SYNC,OPT System Clock Timing Generator RSTN DDIN Data Clock TSTN EIAJ(AES/EBU) Control TST2 Digital Audio Interface Decoder FS1,0 Asynchronous Buffer (1 word per each of DOUT Microcomputer Interface L and R)
  • Page 39 SM-SX1/SX1W IC801 VHiSM5844AF-1: Sampling Rate Converter (SM5844AF) (1/2) • Outline SM5844AF is a special LSI for sampling rate converter, having a function to asynchronously covert the sample rate of the digital audio signal. The input/output interface correspond to the input data of 16/20-bit word length and the output data of 16/18/20-bit word length.
  • Page 40 SM-SX1/SX1W IC801 VHiSM5844AF-1: Sampling Rate Converter (SM5844AF) (2/2) Pin No. Port Name Input/Output Function 34, 35 SLAVE Input with pull-up resistor Mode setting of BCKO, LRCO terminal. H: Output terminal is selected. (Slave mode) L: Input terminal is selected. (Master mode)
  • Page 41 SM-SX1/SX1W IC803 VHiTDA1307/-1: 1-Bit Conversion (TDA1307) (1/2) • Outline The TDA1307 is an advanced oversampling digital filter employing bitstream conversion technology, which has been designed for use in premium performance digital audio applications. Audio data is input to the TDA1307 through its multiple-format interface.
  • Page 42 SM-SX1/SX1W IC803 VHiTDA1307/-1: 1-Bit Conversion (TDA1307) (2/2) Pin No. Port Name Input/Output Function Input (Note 2) Clock input, to be generated by the microprocessor — Ground 1 VDD3 — Supply voltage 2 Input (Note 2) Command/peak data request line Notes 1.
  • Page 43 SM-SX1/SX1W IC903~IC905 VHiBU2114F+-1: LED Driver (BU2114F) • Outline It is the low power consuming CMOS IC which has the latch in the 8-bit shift register and can asynchronously latch the data latched in the shift register. Since the output (O1 to O8) is the open drain output (Since the protective diode is not provided, the voltage of VDD or more to max.
  • Page 44 SM-SX1/SX1W IC907 RH-iX2845AFZZ: System Microcomputer (IX2845AF) Pin No. Port Name Terminal Name Input/Output Function LED3, P83 DATA_IN Input External IC communication input LED2, P82 DATA_OUT Output External IC communication output LED1, P81 IC_CLK Input External IC communication clock LED0, P80 —...
  • Page 45 SM-SX1/SX1W IC907 RH-iX2845AFZZ: System Microcomputer (IX2845AF) AUX3 LED3,P83 DATA-IN DIG_MUTE LED2,P82 DATA-OUT DIG_A LED1,P81 IC_CLK DIG_B LED0,P80 IC_STB AN0,PA0 P22,IRQ2 P_IN AN1,PA1 P21,IRQ1,SENS VOLDIS PROTECT AN2,PA2 P20,IRQ0 KEYA D DATA AN3,PA3 P14,TM4IO KEYB D LATCH AN4,PA4 P13,TM3IO KEYC D CLK...
  • Page 46 SM-SX1/SX1W ICA1 RH-iX2815AFZZ: 7th Order Modulation Conversion LSI (IX2815AF) Pin No. Port Name Input/Output Function VDDR — R channel digital output section power terminal OUTL (+) Output R channel forward output terminal OUTL (–) Output R channel reverse output terminal GNDD —...
  • Page 47: Parts Guide

    “HOW TO ORDER REPLACEMENT PARTS” To have your order filled promptly and correctly, please furnish the For U.S.A. only following information. Contact your nearest SHARP Parts Distributor to order. 1. MODEL NUMBER 2. REF. No. 3. PART NO. 4. DESCRIPTION For location of SHARP Parts Distributor, Please call Toll-Free;...
  • Page 48: Integrated Circuits

    AB Silicon,DAN202K C129 RC-KZ1250AFZZ 0.68µF D304 VHD20E4FD//-1 AC Silicon,20E4FD 0.0015 µF,50V C130 VCKYTV1HB152J D305~308 VHD1SR154/4-1 AC Silicon,1SR154 [For SM-SX1 Only] D310~315 VHD1SR154/4-1 AC Silicon,1SR154 AA 0.0015 µF,16V C131 VCTYBT1CX152M D316~323 VHDDAN202K/-1 AB Silicon,DAN202K [For SM-SX1 Only] AA 0.0015 µF,16V D324~327...
  • Page 49 SM-SX1/SX1W PRICE PRICE DESCRIPTION PARTS CODE DESCRIPTION PARTS CODE RANK RANK AD 0.22 µF,100V,Ceramic AD 2.2 µF,10V C311 RC-KZ1255AFZZ CA81~86 RC-KZ1218AFZZ AB 0.22 µF,16V AF 0.56 µF,250V,Electrolytic C312 VCKYTV1CF224Z CA801~804 RC-FZ1139AFZZ AB 10 µF,25V,Electrolytic AE 0.22 µF,250V.DC C313,314 RC-EZY106AF1E CA805~810 RC-FZ1137AFZZ AB 100 µF,16V,Electrolytic...
  • Page 50 AL Core R917~922 VRS-TV2AB102J AA 1 kohm,1/10W CORE2 RCORF0127AFZZ AN Core R923 VRS-TV2AB103J AA 10 kohm,1/10W F501 QFS-B402DAFN1 Fuse,4A/125V [For SM-SX1] R924~926 VRS-TV2AB102J AA 1 kohm,1/10W F501 QFS-C322KAFNI AF Fuse,T3.15A L 250V R927,928 VRS-TV2AB680J AA 68 ohms,1/10W [For SM-SX1W] R929...
  • Page 51 DESCRIPTION PARTS CODE DESCRIPTION PARTS CODE RANK RANK GCOVA3141AFF1 AH Screw Cover B TSPC-3993AFSA Label,Specifications GITAR0320AFSA AZ Panel,Terminal [SM-SX1 For Central America] GLEGM0103AFFW J AK Spike Leg TSPC-4004AFSA Label,Specifications LANGK0985AFF1 AX Bracket,Front Panel [SM-SX1W For Australia/New LANGK0986AFFF Bracket,Volume Zealand] LANGK0987AFF1...
  • Page 52 DESCRIPTION RANK RANK P.W.B. ASSEMBLY (Not Replacement Item) PWB-A1~9 DCEKL0784AF03 –– Main/Digital/Speaker Relay/Input Source/Segment/AC Input Filter/ Select Switch/Micromputer/ Power (Combined Ass'y) [ SM-SX1] PWB-A1~9 DCEKL0784AF06 –– Main/Digital/Speaker Relay/Input Source/Segment/AC Input Filter/ Select Switch/Micromputer/ Power (Combined Ass'y) [For SM-SX1W] PWB-B DCEKM0388AF03 ––...
  • Page 53 SM-SX1/SX1W 624x5 625x10 625x10 261x2 SOC501 602x2 220x2 619x2 221x2 616x5 623x3 602x8 PWB-A9 with 220,221 PWB-A3 621x2 PWB-A2 602x4 601x2 621x2 218x4 607x2 621x2 623x3 227x5 230x5 610x5 PWB-A7 with PWB-A5 607x2 609x4 621x2 Figure 5 CABINET EXPLODED VIEW (1/2)
  • Page 54 SM-SX1/SX1W 257x2 257x2 602x4 602x4 247x2 257x2 QA10 620x4 PWB-B 613x4 620x4 617x2 613x2 210 210 IC303 Q304 604x2 217x2 Q309 217x2 232x2 618x5 PWB-A6 PWB-A8 PWB-A1 233x4 PWB-A4 215x5 213x3 602x5 602x5 601x5 216x2 602x2 602x2 606x2 605x2 616x2...
  • Page 55 SM-SX1/SX1W PACKING OF PARTS (FOR U.S.A. ONLY) SPAKZ0562AFZZ Setting position of switches and knobs Pad, Top/Rear VOLUME Leg Cushion AC Power Supply Cord SSAKA0226AFZZ Warranty Card Polyethylene Bag, Accessories Operation Manual SPAKZ0554AFZZ Pad, Protect SPAKA2756AFZZ Packing Add.,Left SPAKA2755AFZZ Packing Add.,Right...
  • Page 56 SM-SX1/SX1W © COPYRIGHT 2000 BY SHARP CORPORATION ALL RIGHTS RESERVED. No part of this publication may be reproduced, stored in a retrieval system, or transmitted in any from or by any means, electronic, mechanical, photocopying, recording, or otherwise, without prior written permission of the publisher.

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