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STR-DB840/DB940 SERVICE MANUAL US Model Canadian Model AEP Model UK Model STR-DB840/DB940 E Model Australian Model Chinese Model STR-DB940 Photo: STR-DB940 (AEP and UK models) (Black type) Manufactured under license from Dolby laboratories. “Dolby”, “AC- 3”, “Pro Logic” and the double-D symbol ; are trademarks of Dolby Laboratories.
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• Abbreviation AU : Australian model CN : Chinese model CA : Canadian model SP : E model CED : AEP and UK models : US model...
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SONY PARTS WHOSE PART NUMBERS APPEAR AS DE FONCTIONNEMENT. NE REMPLACER CES COM- SHOWN IN THIS MANUAL OR IN SUPPLEMENTS PUB- POSANTS QUE PAR DES PIÈCES SONY DONT LES LISHED BY SONY. NUMÉROS SONT DONNÉS DANS CE MANUEL OU DANS LES SUPPLÉMENTS PUBLIÉS PAR SONY.
SECTION 1 GENERAL FRONT PANEL PARTS DESCRIPTION MASTER VOLUME MULTI CHANNEL DECODING DIMMER DISPLAY BASS BOOST PRESET CINEMA STUDIO EX. FM / AM SHIFT – A.F.D. 2 CH – MODE ANLG DIRECT 5.1CH INPUT TUNING SPEAKERS DOOR OPEN FUNCTION MUTING MEMORY –...
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5 PRE OUT jack qg TAPE jack (STR-DB940) 6 IMPEDANCE SELECTOR switch qh MD/DAT jack (STR-DB940) 7 AC OUTLET connector MD/TAPE jack (STR-DB840) 8 AC power cord qj CD jack 9 CONTROL A1II jack qk PHONO jack q; 2ND AUDIO OUT jack (STR-DB940)
SECTION 2 DISASSEMBLY Note: Follow the disassembly procedure in the numerical order given. CASE 3 case ass'y 1 two screws (flat head) 1 two screws (flat head) 1 two screws (flat head) 1 two screws (flat head) 5.1 IN BOARD, AU SW BOARD, TUNER 5 5.1 IN board, AU SW board 1 wire (flat type) (15 core)
SECTION 3 TEST MODE Fluorescent Indicator Tube Test Mode AM Channel Step 9 kHz/10 kHz Selection Mode (US and Canadian Models) All fluorescent segments are tested. When this test is activated, all segments turn on at the same time, then each segment turns on Either the 9 kHz step or 10 kHz step can be selected for the AM one after another.
STR-DB840/DB940 4-2. BLOCK DIAGRAM – MAIN Section (2/2) – (DB940) VIDEO SELECT IC2005 J810-2 VIDEO 3 VIDEO INPUT –5V J2003 TV/SAT VIDEO IN VIDEO (SW1) DVD/LD VIDEO IN VIDEO (SW2) SYSTEM CONTROLLER VIDEO OUT V2 OUT VIDEO (SW3) IC1201 (2/2)
4-4. NOTE FOR PRINTED WIRING BOARDS AND SCHEMATIC DIAGRAMS • Circuit Boards Location Note on Printed Wiring Board: Note on Schematic Diagram: • X : parts extracted from the component side. • All capacitors are in µF unless otherwise noted. pF: µµF •...
STR-DB840/DB940 4-5. SCHEMATIC DIAGRAM – DIGITAL Board (1/3) – • See page 42 for Waveforms. • See page 42 for IC Block Diagrams. (Page 16) (Page 17) (Page 39) (Page 32) (Page 27) (Page 29) (Page 29) The components identified by mark 0 or dotted Les composants identifiés par une marque 0 sont...
STR-DB840/DB940 4-7. SCHEMATIC DIAGRAM – DIGITAL Board (3/3) – • See page 42 for Waveform. • See page 42 for IC Block Diagrams. (Page 16) (Page 25) (Page 15) The components identified by mark 0 or dotted Les composants identifiés par une marque 0 sont line with mark 0 are critical for safety.
STR-DB840/DB940 4-19. SCHEMATIC DIAGRAM – DISPLAY Board – • See page 42 for Waveforms. • See page 42 for IC Block Diagrams. (Page 23) (Page 35) (Page 35) (Page 35) (Page 35) (Page 15) (Page 15) The components identified by mark 0 or dotted Les composants identifiés par une marque 0 sont...
STR-DB840/DB940 4-28. PRINTED WIRING BOARDS – DC (1)/DC (2) Boards – • See page 14 for Circuit Boards Location. DC (2) BOARD MAIN BOARD (Page 30) CNP811 AC BOARD AC BOARD CNV902 CNV902 (Page 40) DC (1) BOARD AC BOARD...
STR-DB840/DB940 4-29. SCHEMATIC DIAGRAM – DC (1)/DC (2) Boards – (Page 33) (Page 33) (Page 33) (Page 15) (Page 41) (Page 41) The components identified by mark 0 or dotted Les composants identifiés par une marque 0 sont line with mark 0 are critical for safety.
STR-DB840/DB940 4-31. SCHEMATIC DIAGRAM – AC/SP Boards – (Page 39) (Page 39) (Page 33) (Page 33) (Page 33) The components identified by mark 0 or dotted Les composants identifiés par une marque 0 sont line with mark 0 are critical for safety.
4-32. IC PIN FUNCTION DESCRIPTION • DIGITAL BOARD IC1101 LC89055W-RA8 (AUDIO INTERFACE RECEIVER) Pin No. Pin Name Description DISEL Input data select terminal (fixed at “L” in this set) DOUT EIAJ data and parity output terminal Not used DIN0 Amp integrate data input from the select switch (IC1005) DIN1 Amp integrate data input terminal Not used (fixed at “L”) DIN2...
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Pin No. Pin Name Description DOSEL0 Data select 0 output terminal (fixed at “L” in this set) DOSEL1 Data select 1 output terminal (fixed at “L” in this set) CKSEL0 System clock select 0 input terminal (fixed at “L” in this set) CKSEL1 System clock select 1 input terminal (fixed at “L”...
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• DIGITAL BOARD IC1201 MB90573PFV-G-296-BND (SYSTEM CONTROLLER) Pin No. Pin Name Description SCLK Serial clock signal output to the dolby digital audio decoder (IC1301) Serial data input from the dolby digital audio decoder (IC1301) Serial data output to the dolby digital audio decoder (IC1301) Chip select signal output to the dolby digital audio decoder (IC1301) Reset signal output to the dolby digital audio decoder (IC1301) DSIG...
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Pin No. Pin Name Description SDATA Tuner data output to the FM/AM tuner unit (TM301) SCLK Tuner clock signal output to the FM/AM tuner unit (TM301) DATA IN PLL data input from the FM/AM tuner unit (TM301) AUSTOP Tuned display detection signal input from the FM/AM tuner unit (TM301) STEREO Stereo detection signal input from the FM/AM tuner unit (TM301) 61, 62...
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Pin No. Pin Name Description DIG-INB Digital input select B control signal output to the select switch (IC1005) DIG-INA Dgital input select A control signal output to the select switch (IC1005) XMODE Reset signal output to the digital audio interface receiver (IC1101) Clock signal output to the digital audio interface receiver (IC1101) Chip enable signal output to the digital audio interface receiver (IC1101) Data output to the digital audio interface receiver (IC1101)
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• DIGITAL BOARD IC1401 CXD2712R (AUDIO DSP) Pin No. Pin Name Description VSS3 — Ground terminal 2 to 5 SOA to SOD Serial data output to the A/D, D/A converter 6, 7 ECJ0, ECJ1 Conditional jump input terminal (fixed at “L” in this set) Not used (fixed at “L”) XHDWR Write data input from the system controller (IC1201)
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Pin No. Pin Name Description CLKI Master clock signal input terminal (10MHz) CLKO Master clock signal output terminal (10MHz) VSS1 — Ground terminal VDD0 — Power supply terminal (+3.3V) AVSS — Ground terminal (for PLL cell) AVDD — Power supply terminal (+3.3V) (for PLL cell) PLLCK PLL output/test clock signal input terminal (for check) PLL cell oscillation enable signal input terminal...
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• DIGITAL BOARD IC1503 AK4527 (A/D, D/A CONVERTER) Pin No. Pin Name Description SDOS Data source select terminal “L”: internal ADC output “H”: DAUX input Control mode select terminal “L”: 3-wire serial “H”: I2C bus SMUTE Soft mute signal input from the system controller (IC1201) BCLK Audio serial data clock signal input from the digital audio interface receiver (IC1101) LRCK...
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• DISPLAY BOARD IC102 MB90553ABPF-G-169-BND (DISPLAY CONTROLLER) Pin No. Pin Name Description EQUALIZER indicator (D123) drive signal output terminal “L”: on SURROUND indicator (D122) drive signal output terminal “L”: on LEVEL LEVEL indicator (D119) drive signal output terminal “L”: on NAME NAME indicator (D151) drive signal output terminal “L”: on SETUP...
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Pin No. Pin Name Description MD 2 signal input from the system controller (IC1201) HW STANDBY Hardware standby signal input to the power control (IC1206) RDS CLOCK Clock signal input from the RDS decoder (IC1) RDS DATA Data input from the RDS decoder (IC1) OSD VSYNC Video sync signal output to the video switch (IC2005) (used for STR-DB940 only) OSD VBLK...
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Pin No. Pin Name Description Learning microprocessor latch signal output to the SIRCS driver (IC106) (used for STR-DB940 only) RESET Reset signal output to the SIRCS driver (IC106) (used for STR-DB940 only) OSD LAY Video latch signal output to the video switch (IC2004) (used for STR-DB940 only)
(US, CND, AEP, UK, AUS) X-4950-431-1 CASE ASSY (BLACK) (US, CND, AEP, UK, AUS) X-4950-432-1 CASE ASSY (SILVER) (AEP, UK, AUS) 4-942-568-51 EMBLEM (NO.5), SONY (E, CH) X-4950-437-1 CASE ASSY (CH) 4-942-568-61 EMBLEM (NO.5), SONY (SILVER) X-4952-845-1 CASE ASSY (E)
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(2) FRONT PANEL SECTION DB940 FL101 not supplied not supplied supplied Ref. No. Part No. Description Remark Ref. No. Part No. Description Remark 4-227-129-01 PANEL, FRONT (BLACK) 1-677-007-11 POWER BOARD (DB940: US, CND, AUS) X-4952-753-1 BRACKET (DAMPER L) ASSY 4-227-129-11 PANEL, FRONT (BLACK) (DB940: AEP, UK) 3-973-975-31 DAMPER, OIL 4-227-129-21 PANEL, FRONT (E, CH) 1-677-006-11 SW BOARD...
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(3) CHASSIS SECTION-1 supplied T901 supplied US, CND AEP, UK, E supplied The components identified by Les composants identifiés par une mark 0 or dotted line with marque 0 sont critiques pour la mark 0 are critical for safety. sécurité. Replace only with part num- Ne les remplacer que par une pièce ber specified.
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(4) CHASSIS SECTION-2 supplied supplied supplied supplied not supplied TM301 supplied not supplied not supplied supplied supplied not supplied Ref. No. Part No. Description Remark Ref. No. Part No. Description Remark 1-677-009-11 VOL BOARD 4-227-151-71 PANEL, BACK (DB840: US) 1-677-010-11 VIDEO 3 BOARD 4-227-151-81 PANEL, BACK (DB840: AEP, UK) 1-677-011-11 H.P BOARD 4-227-151-91 PANEL, BACK (DB840: CND)
SECTION 6 5.1 IN ELECTRICAL PARTS LIST NOTE: • Due to standardization, replacements in the • Items marked “*” are not stocked since they The components identified by mark 0 or dotted line with mark parts list may be different from the parts speci- are seldom required for routine service.
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AU SW Ref. No. Part No. Description Remark Ref. No. Part No. Description Remark A-4428-871-A AU SW BOARD, COMPLETE (DB840) C1562 1-128-858-11 ELECT 22uF A-4428-872-A AU SW BOARD, COMPLETE (EXCEPT DB940: AEP, UK) (DB940: US, CND, E, AUS, CH) C1563 1-119-825-41 ELECT 22uF A-4428-873-A AU SW BOARD, COMPLETE (DB940: AEP, UK)
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AU SW BIAS (C) BIAS (L) BIAS (LS) BIAS (R) Ref. No. Part No. Description Remark Ref. No. Part No. Description Remark R1529 1-216-033-00 METAL CHIP 1/10W < RESISTOR > R1530 1-216-033-00 METAL CHIP 1/10W R621 1-247-843-11 CARBON 3.3K 1/4W R1532 1-216-085-00 METAL CHIP 1/10W...
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DIGITAL Ref. No. Part No. Description Remark Ref. No. Part No. Description Remark IC1204 8-759-231-53 IC M5F7805L R1104 1-216-022-00 METAL CHIP 1/10W IC1205 8-759-231-53 IC M5F7805L R1105 1-216-066-00 METAL CHIP 5.1K 1/10W IC1206 8-759-544-04 IC NJM2103M-TE2 R1106 1-216-071-00 METAL CHIP 8.2K 1/10W IC1207 8-759-231-53 IC M5F7805L...
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S-VIDEO VIDEO VIDEO 3 Ref. No. Part No. Description Remark Ref. No. Part No. Description Remark C202 1-126-964-11 ELECT 10uF < IC > C203 1-126-964-11 ELECT 10uF C204 1-126-964-11 ELECT 10uF IC251 8-759-529-20 IC NJM2296D C205 1-128-805-11 CERAMIC 47PF IC252 8-759-529-20 IC NJM2296D IC253 8-759-666-33 IC NJM2145D (US, CND)
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VIDEO 3 Ref. No. Part No. Description Remark Ref. No. Part No. Description Remark < EARTH TERMINAL > ************** HARDWARE LIST * EB702 1-537-738-21 TERMINAL, EARTH ************** < JACK > 7-685-646-79 SCREW +BVTP 3X8 TYPE2 IT-3 7-685-853-04 SCREW +BVTT 2X6 (S) J809 1-784-808-11 TERMINAL, S (VIDEO 3 INPUT) 7-685-645-79 SCREW +BVTP 3X6 TYPE2 IT-3...
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Ref. No. Part No. Description Remark Ref. No. Part No. Description Remark 4-978-977-01 LID, BATTERY CASE (for RM-PP404) 8-917-423-90 REMOTE COMMANDER RM-PP404 (DB840: AEP, UK)
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STR-DB840/DB940 Sony Corporation 9-929-215-11 2000D0585-1 Audio Entertainment Group Printed in Japan C 2000. 4 Published by HA Quality Assurance Dept.