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XR-4900 3 7 63 1515 0 SERVICE MANUAL E Model Model Name Using Similar Mechanism XR-C5100 Tape Transport Mechanism Type MG-25F-136 SPECIFICATIONS L 13942296513 – Continued on next page – FM/MW/SW CASSETTE CAR STEREO u163 MICROFILM http://www.xiaoyu163.com...
http://www.xiaoyu163.com 3 7 63 1515 0 TABLE OF CONTENTS GENERAL Location of Controls ............3 Resetting the Unit ............4 Detaching the Front Panel ..........4 Setting the Clock ............. 4 Installation ............... 5 Connections ..............6 DISASSEMBLY ............9 ASSEMBLY OF MECHANISM DECK ....
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http://www.xiaoyu163.com SECTION 1 This section is extracted from instruction manual. GENERAL 3 7 63 1515 0 L 13942296513 u163 – 3 – http://www.xiaoyu163.com...
http://www.xiaoyu163.com SECTION 2 DISASSEMBLY 3 7 63 1515 0 Note: Follow the disassembly procedure in the numerical order given. FRONT PANEL ASS’Y 1 Push the button (release). 2 Remove the front panel ass’y to the direction of the arrow A . L 13942296513 COVER ASS’Y 3 cover ass’y...
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http://www.xiaoyu163.com 3 7 63 1515 0 SUB PANEL, MECHANISM DECK (MG-25F-136) 5 screw (PTT2.6 × 6) 3 connector (CN351) 6 mechanism deck (MG-25F-136) 4 flexible flat cable (CN301) 2 sub panel 1 three screws (PTT2.6 × 8) L 13942296513 1 three screws (PTT2.6 ×...
http://www.xiaoyu163.com SECTION 3 3 7 63 1515 0 ASSEMBLY OF MECHANISM DECK Note: Follow the assembly procedure in the numerical order given. 5 Fit projection on C part. HOUSING 7 Holder the hanger by bending the claw. 2 Install the hanger onto two claws of the housing.
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http://www.xiaoyu163.com 3 7 63 1515 0 LEVER (LDG-A) / (LDG-B) shaft A shaft A shaft B shaft B shaft C 1 Fit the lever (LDG-A) on shafts A – C and install it. 3 type-E stop ring 2.0 2 Fit the lever (LDG-B) on shafts A and B and install it.
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http://www.xiaoyu163.com 3 7 63 1515 0 GUIDE (C) 2 guide (C) 1 three claws L 13942296513 MOUNTING POSITION OF CAPSTAN/REEL MOTOR (M901) 30 ° 3 Capstan/reel motor(M901) 2 Two precision screws (P 2 × 2) u163 1 Belt – 13 – http://www.xiaoyu163.com...
http://www.xiaoyu163.com SECTION 5 SECTION 4 ELECTRICAL ADJUSTMENTS MECHANICAL ADJUSTMENTS 3 7 63 1515 0 1. Clean the following parts with a denatured-alcohol-moistene TEST MODE swab: This set have the test mode function. In the test mode, FM Auto playback head pinch roller Scan/Stop Level and MW Auto Scan/Stop Level adjustments can rubber belt capstan...
http://www.xiaoyu163.com 3 7 63 1515 0 FM Stereo Separation Adjustment TUNER SECTION 0 dB=1 µV Setting: [SOURCE] button: FM Cautions during repair FREQUENCY SELECT switch: FM200 k When the tuner unit is defective, replace it by a new one be- FM RF signal cause its internal block is difficult to repair.
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http://www.xiaoyu163.com 3 7 63 1515 0 MW Auto Scan/Stop Level Adjustment Make this adjustment after “FM Auto Scan/Stop Level Adjustment”. Setting: [SOURCE] button: MW FREQUENCY SELECT switch: MW10 k 30 Ω 15 pF 65 pF AM RF signal generator AM dummy antenna (50 Ω...
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http://www.xiaoyu163.com 3 7 63 1515 0 Adjustment Location: – SET UPPER VIEW – Tape Speed Adjustment TU 1 RV 1 MW Auto Scan/Stop Level Adjustment RV 2 FM Auto Scan/Stop Level Adjustment RV 4 FM Stereo Separation Adjustment L 13942296513 u163 –...
http://www.xiaoyu163.com SECTION 6 DIAGRAMS 3 7 63 1515 0 • Waveforms THIS NOTE IS COMMON FOR PRINTED WIRING BOARDS AND SCHEMATIC DIAGRAMS. (In addition to this, the necessary note is printed 2.8Vp-p in each block.) For schematic diagrams. 18.432MHz Note: IC501 !™...
http://www.xiaoyu163.com 3 7 63 1515 0 6-6. IC PIN FUNCTION DESCRIPTION • IC501 MASTER U-COM (MN101C12GTB1) Pin No. Pin Name Function VREF- – Basic voltage (- side) of AD conversion input FM/AM common signal meter A/D conversion input terminal KEYIN1 KEY (AD conversion) input KEYIN0 DBASS IN...
http://www.xiaoyu163.com 3 7 63 1515 0 Pin No. Pin Name Function Not used AMSON “L” is output in AMS mode N/R-OUT FOR/REV control output MTLON Metal control input/output TAPMUT Tape mute control output DOLON Dolby control input/output AMSIN Input to detect existence of song during AMS mode 57 to 75 Not used Combination stereo input and monaural output...
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http://www.xiaoyu163.com SECTION 7 EXPLODED VIEWS 3 7 63 1515 0 NOTE: • The mechanical parts with no reference number in • -XX, -X mean standardized parts, so they may have the exploded views are not supplied. some difference from the original one. •...
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http://www.xiaoyu163.com 3 7 63 1515 0 (2) FRONT PANEL SECTION not supplied (KEY board) LCD901 L 13942296513 Ref. No. Part No. Description Remark Ref. No. Part No. Description Remark 3-030-838-01 BUTTON (RELEASE) * 61 3-030-839-01 SHEET (REFLECTOR) 3-030-832-01 LEVER (S/A) 3-932-475-01 SPRING (RELEASE) * 62 3-030-824-01 PLATE, LIGHT GUIDE...
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http://www.xiaoyu163.com 3 7 63 1515 0 (3) MECHANISM DECK SECTION (MG-25F-136) HP901 M901 L 13942296513 Ref. No. Part No. Description Remark Ref. No. Part No. Description Remark A-3291-667-A CLUTCH (FR) ASSY 3-933-346-01 CATCHER 3-019-130-01 LEVER (LDG-A) 3-933-344-01 GUIDE (C) 3-019-131-01 LEVER (LDG-B) 3-014-798-01 SCREW (HEAD), SPECIAL 3-020-539-01 SPRING (LD-1), TENSION 3-364-151-01 WASHER...
http://www.xiaoyu163.com SECTION 8 ELECTRICAL PARTS LIST 3 7 63 1515 0 Note: • SEMICONDUCTORS • Due to standardization, replacements in the parts list When indicating parts by reference In each case, u: µ , for example: may be different from the parts specified in the number, please include the board uA...: µ...
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http://www.xiaoyu163.com MAIN 3 7 63 1515 0 Ref. No. Part No. Description Remark Ref. No. Part No. Description Remark R991 1-216-295-00 SHORT 1-124-234-00 ELECT 22uF R999 1-216-295-00 SHORT 1-164-004-11 CERAMIC CHIP 0.1uF 1-124-234-00 ELECT 22uF < ROTARY ENCODER > 1-124-234-00 ELECT 22uF RE901 1-475-014-11 ENCODER, ROTARY...