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ORDER NO. VRD0103012C2 Video Cassette Recorder NV-SJ420EG / NV-SJ420EGM / NV-SJ420EGN / NV- SJ420EGY / NV-SJ420B Z-MECHANISM SPECIFICATIONS 2001 Matsushita Electric Industrial Co., Ltd. All rights reserved. Unauthorized copying and distribution is a violation of law.
/ Please refer to the service manual for Z- Mechanism Chassis. (Order No. VRD9802005C2) 2. The Model No. is indicated on the Schematic Diagram and Circuit Board Diagrams as follows. Model No. Indication Mark NV-SJ420EG/EGM/EGN NV-SJ420EGY NV-SJ420B 2. GENERAL DESCRIPTIONS 2.1. SERVICE CAUTION 2.1.1. REPLACING IC7702/EEPROM When the EEPROM: IC7702 is replaced, applicable model code, option code and electrical adjustment data will not be available.
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STEP2.INPUT THE MODEL & OPTION CODE 1. Set up the applicable model code and option code by ordering the following table. PROCEDURE F.I.P. DISPLAY Turn on the Service Mode 1.Press the FF key and the EJECT key simultaneously for more than 3 seconds. Activate the Service Mode 2 2.While keep placing FF key, press the EJECT key in twice.
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2. UPPER CYLINDER DISASSEMBLY A. Remove 2 screws (A). B. Remove the Cylinder Stator Unit. C. Remove 2 screws (B). D. Remove the Cylinder Rotor Unit. E. Loose Hex screw (C) (1.5 mm) and remove the CYLINDER RETAINER. F. Remove the Upper Cylinder. Fig.
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3. UPPER CYLINDER ASSEMBLY When reassembling, perform the steps in the reverse order. Notes: 1. Install the Cylinder Retainer so that the 2 holes on top of the Cylinder Retainer are at right angles with the P3502 Connection. 2. Tighten the Hex screw (C) (1.5 mm) while pressing down on top of the Cylinder Retainer.
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3. Install the Cylinder Rotor Unit so that the inner hole of the Cylinder Rotor Unit fits to the small projection (D) on top of the Upper Cylinder. 4. Tighten 2 screws (B). Fig. S6 5. install the Cylinder Stator Unit. 6.
(PAL: VFJ8125H3F) and adjust it if necessary. 2.1.3. CHECKING OF MAIN C.B.A. When servicing the MAIN C.B.A., take out the MAIN C.B.A. and mechanism from the frame and turn over. Fig. S8 2.1.4. FLAT CARD CABLE INSTALLATION When installing the Flat Card Cable on the connector, install the Flat Card Cable with the cable contacts facing the connector contacts.
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2.3. INTRODUCTION OF VIDEO HEAD CLEANING CASSETTE / (POLISHING TYPE) 1. We are pleased to introduce Panasonic Video Head Cleaning Cassette, VFK0923FT [for service purposes] and VFK0923FSE [ for end users] for all VHS/SVHS VCP and VCR. 2. These cleaning cassettes are exclusive removing the hard and sticky clogging on video heads.
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VFK0923FT (For Service usage) Type of Cassette Full VHS Cassette Cleaning Time 10 Seconds/Time Tape Length 20 m Usability in a Path 180 Times VFK0823FSE (For end users) Type of Cassette Full VHS Cassette Cleaning Time 10 Seconds/Time Tape Length 3.34 m Usability in a Path 30 Times...
VFK0823FSE (For end users) Note: The tape material itself is the same in both types. 2.4. SELF-DIAGNOSIS RESULT DISPLAY The "SELF-DIAGNOSIS RESULT DISPLAY & MEMORY function is built in this VTR. It means that when the VCR detects undesirable condition, it can be displayed a “Error code (Two numbers from the left)”...
INDICATION CAUSE REMEDY/CHECK After cylinder lock is detected, the cylinder Check the cylinder motor drive circuit. does not start rotating again even after tape unloading. Cassette tape is not wound up during the tape Check the capstan motor drive circuit. unloading except EJECT mode.
3.1.2. DETAIL OF DISASSEMBLY METHOD 1. REMOVAL OF THE TOP PANEL Remove 4 Screws (A) Fig.D2 2. REMOVAL OF THE FRONT PANEL UNIT Unlock 7 Tabs (B) Fig. D3...
3. REMOVAL OF THE MECHANISM UNIT Remove Screw (C) Remove CYLINDER SHIELD PLATE Remove Screw (D) Remove 3 Screws (E) Remove 2 Screw (F) Note: 1. Keep pressing 2 stoppers on Cassette Holder Plate and Press Cassette Holder Plate to the rear. 2.
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4. REMOVAL OF THE MAIN C.B.A. Remove 4 screws (G) Unlock 4 Tabs (H) Fig. D5 NOTE: Before mounting the MAIN C.B.A. onto the frame, be sure to confirm that the insulation sheet is mounted on the frame as shown in Fig.
Fig. D6 5. SERVICING POSITION Fig. D7 3.2. MECHANICAL ADJUSTMENT PROCEDURES Refer to the Service Manual for Z-Mechanism Chassis. / (Order No. VRD9802005C2) 3.3. ELECTRICAL ADJUSTMENT PROCEDURES 3.3.1. TEST EQUIPMENT The following equipments are required for Electrical Adjustments. 1. Dual-Trace Oscilloscope - Voltage Range: 0.005-5V/div - Frequency Range: DC-35MHz - Probes: 10:1 / 1:1...
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4. Digital Volt Meter (D.V.M.) 5. Video Sweep Generator 6. Sinewave Generator 7. Video Pattern Generator 8. Monitor TV 9. DC Power Supply 10. VHS Blank Tape 11. VHS Alignment Tape - Parts No.: VFJ8125H3F(PAL) 3.3.2. VCR SETTING When no indication in the procedure, set each selector as follows. 1.
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ITEM ADJ. MODE INPUT TAPE M. EQ. SPEC. REMARKS VIDEO / SP/LP/EP / VIDEO / BLANK OSCILLO / SP: 0+-1 Refer to the VIDEO FREQUENCY PLAYBACK SWEEP SCOPE/ / (dB) procedure of TAPE / RESPONSE / (SELF- / (See VIDEO FREQUENCY (90~110%) REC)
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PROCEDURES FIP DISPLAY Press the FF and EJECT Keys simultaneously for 3 seconds. Press the FF and EJECT Keys simultaneously twice. Press the EJECT key for 3 seconds. Press the CH UP key once. Insert the Alignment cassette tape. (PAL:VFJ8125H3F) When the sequence of the automatical adjustment has been terminated, the following action has been made.
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PROCEDURES FIP DISPLAY Press the FF and EJECT Keys simultaneously for 3 seconds. Press the FF and EJECT Keys simultaneously twice. Press the EJECT key for 3 seconds. Press the CH UP key in 3 times. Insert the blank cassette tape. (The adjustment is automatically started.) When the sequence of the automatical adjustment...
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PROCEDURES FIP DISPLAY Connect the Oscilloscope to: *CH1..Video Out (TW3002). *CH2..V.FREQ.(TW6002) Press the "4" key on the remote controller. (Confirm that TW6002 becomes high(5V)). Adjust the Frequency response by pressing the "2"(increase) and/or "8"(decrease) key on the Remote Controller. (See Fig.E2) Store the Adjusted value by pressing the "5"...
11.1. CHASSIS PARTS SECTION PARTS LIST Ref. No. Part No. Part Name & Description Remarks VEG1523 CYLINDER UNIT [SUPPLIED FROM MBV] VXP2002 UPPER CYLINDER UNIT VDB1256 CYLINDER RETAINER VEM0715 CYLINDER MOTOR UNIT VXS0135 EARTH BRUSH VMD3795 FLAT CABLE HOLDER VEK9069 CAPSTAN UNIT L1AZ00000004 FE HEAD...
Ref. No. Part No. Part Name & Description Remarks VGM1733 TOP PANEL VYP8020 FRONT PANEL UNIT [SUPPLIED FROM MBV]NV-SJ420EG-S/ EGMS/EGNS/EGYS VYP8021 FRONT PANEL UNIT [SUPPLIED FROM MBV]NV-SJ420B RKA0072-K FOOT RKA0072-K FOOT VKA0191 VKA0191 VGB0554 SUPER DRIVE BADGE [SUPPLIED FROM MBV]...
Ref. No. Part No. Part Name & Description Remarks VQT9037 OPERATING INSTRUCTIONS(GERMAN) [SUPPLIED FROM MBV]NV- SJ420EG-S/EGMS/EGYS VQT9038 OPERATING INSTRUCTIONS(FRENCH) [SUPPLIED FROM MBV]NV- SJ420EG-S/EGMS/EGYS VQT9040 OPERATING INSTRUCTIONS(ITALIAN) [SUPPLIED FROM MBV]NV- SJ420EG-S/EGYS VQT9039 OPERATING INSTRUCTIONS(SPANISH) [SUPPLIED FROM MBV]NV- SJ420EG-S VQT9041 OPERATING INSTRUCTIONS(DUTCH) [SUPPLIED FROM MBV]NV- SJ420EG-S/EGMS VQT9042...
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[SUPPLIED FROM MBV](RTL) NV-SJ420B-S THE FOLLOWING C.B.A. IS INCLUDED IN MAIN C.B.A. VEP07A23P VEP06D85N MAIN C.B.A. [SUPPLIED FROM MBV](RTL) NV-SJ420EG-S/EGNS/EGMS THE FOLLOWING C.B.A. IS INCLUDED IN MAIN C.B.A. VEP07A23N VEP06E00J MAIN C.B.A. [SUPPLIED FROM MBV](RTL) NV-SJ420EGYS THE FOLLOWING C.B.A. IS INCLUDED IN MAIN C.B.A.
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CYLINDER SERVO SPEED LOOP P2901 MAIN COIL 2 MAIN COIL 3 HALL IC GND (CYL) MAIN COIL 1 NOTE:DO NOT USE ANY PART NUMBER SHOWN ON THIS SCHEMATIC DIAGRAM FOR ORDERING.WHEN YOU ORDER A PART,PLEASE REFER TO PARTS LIST.
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VIDEO MAIN SIGNAL PATH IN REC MODE VIDEO MAIN SIGNAL PATH IN PLAYBACK MODE AUDIO MAIN SIGNAL PATH IN REC MODE AUDIO MAIN SIGNAL PATH IN PLAYBACK MODE :TO POWER SUPPLY/RF SECTION :TO SYSTEM CONTROL & SERVO SECTION :TO LUMINANCE & CHROMINANCE/AUDIO SECTION L4903 R4945 C4925...
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:TO POWER SUPPLY/RF SECTION THE STRIPED FRAME INDICATES THE PRIMARY CIRCUIT TO DISTINGUISH THE PRIMARY CAUTION :TO TIMER SECTION FROM THE SECONDARY CIRCUIT. PAY ATTENTION NOT TO RECEIVE AN ELECTRIC SHOCK DURING REPAIR AND SERVICE OF THE PRODUCTS. T1101 ETE28K131AZ LB1102 C1101 D1125...
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VIDEO MAIN SIGNAL PATH IN REC MODE AUDIO MAIN SIGNAL PATH IN REC MODE VIDEO MAIN SIGNAL PATH IN PLAYBACK MODE AUDIO MAIN SIGNAL PATH IN PLAYBACK MODE :TO POWER TRANSFORMER SECTION :TO SYSTEM CONTROL & SERVO SECTION TU7601 Q1002 Q1006 TUNER UNIT :TO LUMINANCE &...
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VIDEO MAIN SIGNAL PATH IN REC MODE VIDEO MAIN SIGNAL PATH IN PLAYBACK MODE AUDIO MAIN SIGNAL PATH IN REC MODE AUDIO MAIN SIGNAL PATH IN PLAYBACK MODE :TO POWER SUPPLY/RF SECTION S :TO SYSTEM CONTROL & SERVO SECTION I :TO INPUT/OUTPUT SECTION IC3501 :TO TIMER SECTION AN3368SB...
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IMPORTANT SAFETY NOTICE: COMPONENTS IDENTIFIED WITH THE MARK HAVE THE SPECIAL CHARACTERISTICS FOR SAFETY. WHEN REPLACING ANY OF THESE COMPONENTS, USE ONLY THE SAME TYPE. THE STRIPED FRAME INDICATES THE PRIMARY CIRCUIT TO DISTINGUISH THE PRIMARY CAUTION FROM THE SECONDARY CIRCUIT. PAY ATTENTION NOT TO RECEIVE AN ELECTRIC SHOCK DURING REPAIR AND SERVICE OF THE PRODUCTS.
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SYSTEM CONTROL & SERVO ICs DC VOLTAGE CHART (SP MODE) IC1501 IC1502 Ref. No. MODE STOP PLAY Ref. No. IC2501 MODE STOP 16.8 16.8 16.8 16.8 PLAY 14.9 14.9 15.2 14.9 15.1 15.1 15.4 15.1 14.4 14.4 14.6 14.7 14.3 14.3 14.6 14.9...
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No. Port Name Description P-OFF P-Save P-FAIL Reset CURRENT_LIMIT O Capstan motor current limit terminal. F ADJUST O Analogue voltage output for HEAD frequency response adjustment N.C. -- Low fix (No Connection.) Terminal of the Current emphasis video/FM audio recording current. [HIFI/2HEAD ]:Fix to Low (Normal mode) C EMPHA(H) [4HEAD]...
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No. Port Name Description P-OFF P-Save P-FAIL Reset ROTARY.SW O Output terminal for rotary switch. H.A.SW O Output terminal for HEAD AMP switch. ENVE.SELECT I Input terminal for enverope selection. VIDEO.H.SW O Output terminal for video HEAD switch. A.H.SW O Output terminal for FM audio HEAD switch. Audio Mute output terminal for tuner and decoder.
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No. Port Name Description P-OFF P-Save P-FAIL Reset LC.OSC OUT O The oscillation output terminal for OSD dot clock. RESET(L) I Input terminal for microprocessor reset. 4FC.LPF I 4fc clock input terminal OSD.FSC IN I OSD clock input terminal 5V(OSD) I 5V input terminal CVIN I Input terminal for Composite video signal.
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No. Port Name Description P-OFF P-Save P-FAIL Reset FLD/T2 DATA OUT O Serial data output terminal for FIP driver and TEST_2(Factory use). Not fix Low FLD_CS O Chip select terminal for FIP driver. Not fix Low T.REEL.PULSE I Input terminal for Take-up Reel sensor pulse. S.REEL.PULSE I Input terminal for Supply Reel sensor pulse.
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INPUT CONDITION VIDEO OUTPUT RESULT AUDIO OUTPUT RESULT POWER INPUT RF (C) AV1 Out AV2 Out SELECT ON(H) PB(H) PB(H) PB(H) Selector Selector AV2 In AV1 In AV2 In AV1 In Mute AV2 In AV1 In AV2 In AV1 In AV2 In AV1 In Mute...
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INPUT CONDITION VIDEO OUTPUT RESULT AUDIO OUTPUT RESULT POWER INPUT RF (C) AV1 Out AV2 Out SELECT ON(H) PB(H) PB(H) PB(H) Selector Selector P.ON NO.TU VCR out VCR out INSEL C+.TU VCR out VCR out INSEL VCR out VCR out AV1 In AV1 In AV1 In...
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INPUT CONDITION VIDEO OUTPUT RESULT AUDIO OUTPUT RESULT POWER INPUT RF (C) AV1 Out AV2 Out SELECT ON(H) PB(H) PB(H) PB(H) Selector Selector P.ON DECODER VTR NO.TU VCR out AV1 In AV1 In AV1 In VCR out AV1 In AV1 In AV1 In C+.TU VCR out TUN IN...
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INPUT CONDITION VIDEO OUTPUT RESULT AUDIO OUTPUT RESULT POWER INPUT RF (C) AV1 Out AV2 Out SELECT ON(H) PB(H) PB(H) PB(H) Selector Selector AV2 In AV1 In AV2 In AV1 In Mute AV2 In AV1 In AV2 In AV1 In AV2 In AV1 In Mute...
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INPUT CONDITION VIDEO OUTPUT RESULT AUDIO OUTPUT RESULT POWER INPUT RF (C) AV1 Out AV2 Out SELECT ON(H) PB(H) PB(H) PB(H) Selector Selector P.ON VCR out VCR out INSEL VCR out VCR out AV1 In AV1 In AV1 In AV1 In INSEL VCR out VCR out AV2 In...
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4.43 NTSC L BILINGUAL 443NT [L] BILINGUAL L A. COMP BIL [L] AUDIO COMPONENT SIGNAL BILINGUAL H BIL. [H] A. COMPO AUDIO COMPONENT SIGNAL BILINGUAL L AUDIO DUBBING PAUSE L BIL/M1 [L] A. D.P [L] AUDIO DUBBING PAUSE L BS CLOCK A.
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CYL GND CYLINDER GND FULL. E. 12V FULL ERASE 12V DELAIED FM RECORDING H D.F.M. REC [H] GND (ANALOG) GND [A] DELAIED FM RECORDING L D. FM REC [L] GND (TUNER) GND [TU] D. GND GND/NON SW 12V DIGITAL GND GND/N.
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POWER OFF H LINE IN [R] LINE INPUT (R) P-OFF [H] POWER OFF L LINE OUT [L] LINE OUTPUT (L) P-OFF [L] LINE OUT [R] LINE OUTPUT (R) P. FAIL POWER FAILURE DETECT LP H POWER OFF H LP [H] P.
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SYSTEM CONTROL 5V RF OUT RF OUTPUT SYSCON 5V SYSTEM SW RF Y RF LUMINANCE SIGNAL SYSTEM TAKE-UP PHOTO TRANSISTOR RF. Y. IN RF LUMINANCE SIGNAL INPUT T-PHOTO TAKE-UP REEL PULSE RF. Y. OUT RF LUMINANCE SIGNAL OUTPUT T-RL. PLS TIMER BUS CLOCK ROTAR.
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If you lose the fuse cover the plug must not be used until a replacement cover is obtained. A replacement fuse cover can be purchased from your local Panasonic Dealer. IF THE FITTED MOULDED PLUG IS UNSUITABLE TYPE B FOR THE SOCKET OUTLET IN YOUR HOME THEN THE FUSE SHOULD BE REMOVED AND THE PLUG CUT OFF AND DISPOSED OF SAFELY.
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IC6001 CAPSTAN IC7501 IC0201 (CAPSTAN MOTOR DRIVE) (SYSTEM CONTROL/SERVO IC) DP7501 MOTOR TL2503 L0201 TL0201 P0201 P2501 MOTOR DIFFERENTIAL TORQUE CURRENT DRIVE AMPRIFIER CONTROL LIMIT TIMER DISPLAY 20MHz IN 31 CAPSTAN P0201 P2501 ERROR TORQUE X6002 20MHz OUT 32 POSITION CAPSTAN P0201 P2501...
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MAIN SIGNAL PATH IN REC MODE MAIN SIGNAL PATH IN PLAYBACK MODE Y/C VIDEO OUT TO/FROM SYSTEM CONTROL VIDEO OUT IC4901 Q4904 SYSTEM C SYNC CONTROL TO TUNER RFC VIDEO OUT CLAMP FROM TV TUNER VIDEO CLAMP DEMODULATOR JK4903 (AV1) PB +12V BLUE GREEN...
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IC3001 PEAKING H-TRAP NLDE DOUB IC3501 PICT TW3030 DELAY AMP & H.AMP FAMI CLP1 P3502 LP L REC-Y FAMI TO/FROM P3502 CYLINDER LP COM VIDEO HEAD MAIN PREAMP P3502 LP R & H.SW FAMI TW3001 H.AMP CLIP L-TRAP &HPF MAIN SYNC CLAMP EMPH...
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R0206 (FG HEAD) R0212 R0213 Q0203 P0201 Q0202 IC0201 R0207 CURR LIMIT (CAPSTAN MOTOR DRIVE) HOLE HOLE CAP ET SENSOR SENSOR CAP ED/S RCC SET CAP FG1 Q0201 GND (FG) R0210 C0201 REG 5V GND (MOTOR) D0203 TL0204 TL0202 TL0203 LOAD MOTOR (-) LOAD MOTOR (+) TL0201...