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COMPONENTS IDENTIFIED BY MARK ON THE SCHEMATIC DIAGRAM AND IN THE PARTS LIST ARE CRITICAL FOR RISK OF FIRE AND ELECTRIC SHOCK. REPLACE THESE COMPONENTS WITH ONKYO PARTS WHOSE PART NUMBERS APPEAR AS SHOWN IN THIS MANUAL. MAKE LEAKAGE-CURRENT OR RESISTANCE...
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Model:TX-8255 No:4088 Component: Printed service manual is not prepared . Title Approve Attached file (Date) Cover 2008/05/29 Specifications / Refer to instruction manual. Panel view / Remote controller Exploded view 2008/06/02 Block diagram 2008/06/24 <---2 Pages (L/R) <---All (Tabloid size)
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Power supply section Packing procedure 2008/05/28 Printed circuit board views Refer to service manual of "TX-8222" (Ref. No. : 3945) IC block diagrams 2008/08/21 Refer to service manual of "TX-8222" Terminal descriptions / (Ref. No. : 3945) FL tube view ------------------------------------------ FL tube Microprocessor terminal descriptions...
TX-8255 EXPLODED VIEW A211 P901 A035 A205 x 2 pcs. x 20 pcs. A208 A207 A210 MPP type only A202 P501A A035 x 8 pcs. A217 x 2 pcs. P704 x 2 pcs. A216 Q524 MDC type only A201 A219...
TX-8255 SCHEMATIC DIAGRAMS-3 DISPLAY SECTION NOTE NADIS-8877 THE COMPONENTS IDENTIFIED BY MARK ARE CRITICAL FOR SAFETY DISPLAY PC BOARD REPLACE ONLY WITH PART NUMBER SPECIFIED. VOLTAGE (MEASURED WITH VOLTMETER) IS DC VOLTAGE.(NO INPUT SIGNAL). Q852 ALL PNP TRANSISTORS ARE EQUIVALENT TO 2SA1015-GR UNLESS OTHERWISE NOTED.
TX-8255 SCHEMATIC DIAGRAMS-4 POWER SUPPLY SECTION MAIN TRANS. NAPS-8880 T901 MDC : NPT-1544D F903 LIST MPP : NPT-1544P VOLTAGE SELECTOR J931 F901 POWER SUPPLY PC BOARD S901 LIST J932 240V P910 AC OUTLET SWITCHED TRANS. SEC. TERMINAL PCB To NAPS-8887...
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TX-8255 PACKING PROCEDURE A801 A805 A822 A802 A823 A606 A803 A807 A824 A804 A605 A605 A821 A603 A605 Front side marking A604 Right side marking A605 A602 Front side A703 ---> MPP type only A601 (L & R) A606 Front side...
TX-8222 PRINTED CIRCUIT BOARD VIEW 4 TRANSFORMER TERMINAL U022 PC BOARD (NAPS-8887) VOLUME PC BOARD U023 U016 TRANSFORMER TERMINAL (NAAF-8888) PC BOARD (NAETC-8881) Reversal letter: :Soldering side parts COMPONENT SIDE SOLDERING SIDE U017 HEADPHONE TERMINAL PC BOARD (NAETC-8882)
TX-8222 PRINTED CIRCUIT BOARD VIEW 1 Reversal letter: :Soldering side parts COMPONENT SIDE COMPONENT SIDE Reversal letter: :Soldering side parts SOLDERING SIDE SOLDERING SIDE U015 MICROPROCESSOR PC BOARD (NADG-8876) PRIMARY CIRCUIT PC BOARD (NAPS-8880)
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TX-8222 MICROPROCESSOR-TERMINAL DESCRIPTION 1 No. Terminal Signal Name Act. Description P96/ANEX1/SOUT4 VSWA Not used. P95/ANEX0/CLK4 VSWB Not used. P94/DA1/TB4IN Not used. P93/DA0/TB3IN Z2SELCLK Not used. P92/TB2IN/SOUT3 Z2SELDAT Not used. P91/TB1IN/SIN3 Z2SELLAT Not used. P90/TB0IN/CLK3 Not used. BYTE BYTE External bus select pin. Connect to Ground. CNVSS CNVss Processor mode select pin...
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TX-8222 MICROPROCESSOR-TERMINAL DESCRIPTION 2 No. Terminal Signal Name Act. Description P31/A09 Not used. VCC2 Vcc2 Power supply pin. P30/A8(/-/D7) SEC1H Not used. Ground pin. P27/AN27/A7(/D7/D6) PROTECT Abnormal voltage and current detection input pin P26/AN26/A6(/D6/D5) VOLH A/D Output signal level detection pin P25/AN25/A5(/D5/D4) THERMAL A/D Thermal detection input pin.
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TX-8255 SERVICE PROCEDURE 1. Replacing the fuses This symbol located near the fuse indicates that the fuse used is show operating type, For continued protection against fire hazard, replace with same type fuse, For fuse rating, refer to the marking adjacent to the symbol.
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TX-8255 OPERATION CHECK-1 SPEAKER PROTECT-1 ( DC VOLTAGE DETECTION / THERMAL SENSOR) DC VOLTAGE DETECTION [When] 1. Exchange power transistors (Q521 - Q524). 2. Exchange amplifier PC board ass'y (NAAF-8886). <Note> 1. Try again if protect did not work at the first time.
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TX-8255 OPERATION CHECK-2 SPEAKER PROTECT-2 (CURRENT DETECTION) [When] 1. Exchange power transistors (Q521 - Q524). 2. Exchange amplifier PC board ass'y (NAAF-8886). <Note> 1. Do not check two channels at the same time. 2. Do not connect a dummy load to speaker terminal longer than 2 seconds.
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TX-8255 ADJUSTMENT PROCEDURE IDLING CURRENT ADJUSTMENT [When] 1. Exchange Power transistor (Q521 - Q524). 2. Exchange Amplifier PC board (NAAF-8886). [Procedure] <Note> No load and No signal Refer to <Fig-1> for the adjustment points and the test points. 1. Before idling adjustment, turn the trimming resistors fully to counter clockwise.
1/30 PAGE TX-8255 <Note> Parts marked by "NSP" are generally unavailable because they are not in our Master Spare Parts List. NOTE : THE COMPONENTS IDENTIFIED BY THE MARK ! ARE CRITICAL FOR RISK OF FIRE AND ELECTRIC SHOCK. REPLACE ONLY WITH PART NUMBER SPECIFIED.
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U13 or TUNER UNIT ENG06507QFUS 240156 <MDC> EXPLODED TUNER UNIT FAE485-E11EU 240154 <MPP> EXPLODED TX-8255 PC BOARD PARTS LIST MICROPROCESSOR PC BOARD (NADG-8876-1M / 1N) PCB1 DISPLAY PC BOARD (NADIS-8877-1M / 1N) PCB1 THERMAL SENSOR PC BOARD (NAETC-8878-1M / 1N) PCB1...
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5/30 PAGE POWER SUPPLY PC BOARD (NAPS-8880-1M / 1N) PCB1 TRANS. TERMINAL PC BOARD (NAETC-8881-1M / 1N) PCB1 HEADPHONE JACK PC BOARD (NAETC-8882-1M / 1N) PCB1 PCB1 CIRCUIT NO. PART NAME DESCRIPTION Q'TY PART NO. (SN) REMARKS PCB1 U851 REMO SENS NJL34H380A 241365 PCB1...
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20/30 PAGE C318 TF C ECQ-B50V-101K 374721015T <MPP> PCB2 C321 TF C ECQ-B50V-101K 374721015T PCB2 <MPP> C322 TF C ECQ-B50V-101K 374721015T PCB2 <MPP> C325 TF C ECQ-B50V-101K 374721015T <MPP> PCB2 C326 TF C ECQ-B50V-101K 374721015T <MPP> PCB2 C327 TF C ECQ-B50V-101K 374721015T <MPP>...
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21/30 PAGE C423 CERA C CK45F50V-223Z 335622230T PCB2 C424 CERA C CK45F50V-223Z 335622230T PCB2 C433 TF C ECQ-B50V-103J 374721034T PCB2 C434 TF C ECQ-B50V-103J 374721034T PCB2 C441 VR C CE04W16V-100M(VR) 394641017T PCB2 C442 VR C CE04W50V-1M(VR) 394680107T PCB2 C501 VX C CE04W50V 47M(VX_BLK) 397384707T PCB2...
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22/30 PAGE C536 TF C ECQ-B50V-102J 374721024T PCB2 C581 VR C CE04W16V-100M(VR) 394641017T PCB2 C582 CERA C CK45F50V-223Z 335622230T PCB2 C583 VR C CE04W50V-1M(VR) 394680107T PCB2 C591 TF C ECQ-B50V-103J 374721034T PCB2 C592 TF C ECQ-B50V-103J 374721034T PCB2 C648 CERA C CK45F50V-223Z 335622230T PCB2...
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23/30 PAGE R305 CARBON R R16J-220K 417342244T PCB2 R306 CARBON R R16J-220K 417342244T PCB2 R307 CARBON R R16J-820 417348214T PCB2 R308 CARBON R R16J-820 417348214T PCB2 R309 CARBON R R16J-470K 417344744T PCB2 R310 CARBON R R16J-470K 417344744T PCB2 R311 CARBON R R16J-39K 417343934T PCB2...
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24/30 PAGE R338 CARBON R R16J-1M 417341054T PCB2 R339 CARBON R R16J-330 417343314T PCB2 R340 CARBON R R16J-330 417343314T PCB2 R341 CARBON R R16J-1M 417341054T PCB2 R342 CARBON R R16J-1M 417341054T PCB2 R349 CARBON R R16J-22K 417342234T PCB2 R350 CARBON R R16J-22K 417342234T PCB2...
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25/30 PAGE R436 CARBON R R16J-2.2K 417342224T PCB2 R441 NF CARBON R R25J-10 415471004T PCB2 R442 NF CARBON R R25J-10 415471004T PCB2 R491 CARBON R R16J-47K 417344734T PCB2 R492 CARBON R R16J-47K 417344734T PCB2 R501 CARBON R R16J-470 417344714T PCB2 R502 CARBON R R16J-470...
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26/30 PAGE R529 METAL O R RS1/2WBJ-47 443524704T PCB2 R530 METAL O R RS1/2WBJ-47 443524704T PCB2 R531 CARBON R R16J-18K 417341834T PCB2 R532 CARBON R R16J-18K 417341834T PCB2 R533 CARBON R R16J-56K 417345634T PCB2 R534 CARBON R R16J-56K 417345634T PCB2 R535 CARBON R R16J-18K...
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27/30 PAGE R566 CARBON R R16J-120K 417341244T PCB2 R567 CARBON R R16J-22 417342204T PCB2 R568 CARBON R R16J-22 417342204T PCB2 R569 CARBON R R16J-22 417342204T PCB2 R570 CARBON R R16J-22 417342204T PCB2 R571 CARBON R R16J-33K 417343334T PCB2 R572 CARBON R R16J-22K 417342234T PCB2...
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28/30 PAGE R644 CARBON R R16J-8.2K 417348224T PCB2 R919 METAL R RNU1/2WCJ-1 453530104T PCB2 R921 METAL R RNU1/2WCJ-0.47 453534794T PCB2 R922 METAL R RNU1/2WCJ-0.47 453534794T PCB2 R923 METAL R RNU1/2WCJ-5.6 453530564T PCB2 R924 METAL O R RS1/2WBJ-560 443525614T PCB2 R931 NF CARBON R R25J-3.3K 415473324T...
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PACKING A702 EAN LABEL 8255 (S) 29390505 (S) <MPP> PACKING A703 LABEL (GW) (9.5kg) 29390660 <MPP> PACKING A801 INS MANUAL En (TX-8255) 29344818 PACKING A802 INS MANUAL U2FrEs (TX-8255) 29344819 PACKING A803 INS MANUAL U2ItDe (TX-8255) 29344820 <MPP> PACKING A804...