Panasonic NV-SJ420EG User manual

ORDERNO. VRD0103012C2
Video Cassette Recorder
NV-SJ420EG / NV-SJ420EGM / NV-SJ420EGN / NV-
SJ420EGY / NV-SJ420B
Z-MECHANISM
SPECIFICATIONS
2001 Matsushita ElectricIndustrial Co., Ltd. All rights reserved.
Unauthorized copying and distribution isaviolation of law.
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1. INTRODUCTION
This service manual contains technical information whichwill allowservice personnel to
understand and service this model.
If the circuit is changedormodified, this information will be followedbysupplementaryservice
manual tobe filedwithoriginal service manual.
Note:
1. Adjustment procedures, DisassemblyProcedures and Assembly
Procedures for Mechanism Chassisare separate volume from this
service manual. / Please refer to the service manual for Z-
Mechanism Chassis. (Order No. VRD9802005C2)
2. The Model No. isindicated on the SchematicDiagram and Circuit
Board Diagrams as follows.
Model No. Indication Mark
NV-SJ420EG/EGM/EGN (A)
NV-SJ420EGY (B)
NV-SJ420B (C)
2. GENERAL DESCRIPTIONS
2.1. SERVICECAUTION
2.1.1. REPLACING IC7702/EEPROM
Whenthe EEPROM: IC7702 is replaced, applicable model code, option code and electrical
adjustment data will not be available.
Therefore, enterand/oradjust the necessarydata afterreplacing IC7702 byreferring following
procedure.
STEP1.REPLACE THE IC7702
1. Remove the C.B.A. with Mechanism unitbyreferring the
Disassemblyprocedure.
2. Disconnect the AC plug and replace the IC7702.
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STEP2.INPUTTHE MODEL& OPTION CODE
1. Set up the applicablemodel code and option code byordering the
following table.
PROCEDURE F.I.P. DISPLAY
Turnon the Service Mode
1.Press the FF keyand the
EJECTkeysimultaneouslyfor
more than3 seconds.
Activate the Service Mode 2
2.While keepplacing FF key,
press the EJECTkeyintwice.
Activate the Entering Mode.
3.Press the EJECTkeyformore
than3 seconds.
Set the Mode 2.
4.Press the CH UP keyintwice.
Displaythe Setting Code.
5.Press the POWER Button to
turnthe poweron.
(Colon starts
flashing)
Enterthe Model and Option Code.
6.Set the applicable Model and Option code by
using REW, PLAY, STOP and FF keys on the
Remote Controller. (See Fig.S1 & S2)
Exit fromService Mode.
7.Press the POWER Button to
turnthe poweroff.
8. Press FF and EJECTkeys
simultaneouslyin6 times.
(Normal
Indication)
Fig.S1 Service Secreen(sample)
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Model No. Model
Code Option Code 1 Option Code 2 Option Code 3
NV-
SJ420EG/ /
EGM/EGN/
EGY
33 / (21h) 8 / (08h) 244 /
(F4h) 6 / (06h)
NV-SJ420B 35 / (23h) 40 / (28h) 244 /
(F4h) 5 / (05h)
Fig. S2 Model Code & Option Code
NOTE:
Since all electrical adjustments data is still not available, perform the Electrical Adjustment
continuously.
2.1.2. CYLINDER UNITREPLACEMENT
1. CYLINDERUNITREPLACEMENT
A. Remove the mechanism unitfrom MAINC.B.A./Chassisby
referring “SECTION2. DisassemblyProcedure”.
B. Remove the 3screws(A)of the CYLINDERUNITwith ascrew
driver.
C. Unlock the 4locking tabs (B)and disconnect the Cylinder
fiexiblecard from the FPCHolder.
D. Remove the CYLINDERUNIT.
CAUTION:
Handlethe Cylinder fiexiblecard with care. When itdamaged, you
shouldreplace wholeCylinder unit.
Fig. S3
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2. UPPERCYLINDERDISASSEMBLY
A. Remove 2screws(A).
B. Remove the Cylinder Stator Unit.
C. Remove 2screws(B).
D. Remove the Cylinder Rotor Unit.
E. Loose Hex screw (C)(1.5mm) and remove the CYLINDER
RETAINER.
F. Remove the Upper Cylinder. Fig. S4
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3. UPPERCYLINDERASSEMBLY
When reassembling, perform the steps inthe reverse order.
Notes:
1. Install the Cylinder Retainer so that the 2holes on top of the
Cylinder Retainer are at right angles with the P3502 Connection.
2. Tighten the Hex screw (C)(1.5mm) whilepressing downon top of
the Cylinder Retainer. Fig. S5
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3. Install the Cylinder Rotor Unitso that the inner holeof the
Cylinder Rotor Unitfits to the small projection (D)on top of the
Upper Cylinder.
4. Tighten 2screws(B). Fig. S6
5. install the Cylinder Stator Unit.
6. Tighten 2screws(A). Fig. S7
7. Confirm the PG SHIFTERADJUSTMENTwith the alignment tape
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(PAL: VFJ8125H3F) and adjust itifnecessary.
2.1.3. CHECKING OFMAIN C.B.A.
Whenservicing the MAIN C.B.A., take out the MAIN C.B.A. and mechanismfromthe frame and
turnover.
Fig. S8
2.1.4. FLATCARD CABLE INSTALLATION
Wheninstalling the Flat CardCable on the connector, install the Flat CardCable withthe cable
contacts facing the connectorcontacts.
Fig. S9
2.2. REMOVALOFCASSETTE TAPE
There are 2 ways toremove a cassette tape.
1. Service Information DisplayOperation
A. Press the FF and EJECTkeyssimultaneoslyfor 3seconds and
set the Service Mode 7.
B. Press STOPkeyinorder to rotate the Loading Motor for
unloading operation. (Payan attention of tape slack)
2. Manual Operation
A. Disconnect the AC Mains Lead and remove the Top Panel.
B. Rotate the MainCam Gear clockwise until the Loading Posts
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move to fullyunloaded position as shownin Fig. S10 . (Tape is
remaining) Fig. S10
C. Rotate the Capstan Motor clockwise from the bottom side to
take up the tape. Fig. S11
D. Rotate the MainCam Gear clockwise until the cassette tape is
ejected.
2.3. INTRODUCTIONOFVIDEO HEAD CLEANING CASSETTE /
(POLISHING TYPE)
1. We are pleased to introduce PanasonicVideo Head Cleaning
Cassette, VFK0923FT [for service purposes] and VFK0923FSE [
for end users] for all VHS/SVHSVCPand VCR.
2. These cleaning cassettes are exclusive removing the hard and
stickyclogging on video heads.
3. These improve the efficiencyof video head cleaning service and
shortening cleaning time for end users.
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VFK0923FT
(ForService usage)
Type of Cassette Full VHS Cassette
Cleaning Time 10 Seconds/Time
Tape Length 20 m
Usabilityina Path 180 Times
VFK0823FSE
(Forend users)
Type of Cassette Full VHS Cassette
Cleaning Time 10 Seconds/Time
Tape Length 3.34 m
Usabilityina Path 30 Times
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