Panasonic Omnivision PV-V4621 User manual

ORDERNO. MKE0101002C1
B3
Video Cassette Recorder
PV-V4621 / PV-V4621-K / PV-V4661-K
SPECIFICATIONS
2001 Matsushita-Kotobuki Electronics Industries Ltd. All rights
reserved. Unauthorized copying and distribution isaviolation of
law.
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1. PV-V4621 REPLACEMENT NOTE
There are 2 types of MainC.B.A. (E10) forPV-V4621.
VEPS6073HA is usedinearlyproducts and has beenchangedtoVEPS6073HC on running
change basis inlaterproducts. Whenreplacing MicrocontrollerIC (IC6001) orEEP ROM IC
(IC6005), be sure toconfirm whichMainC.B.A. is usedforthe unit you are servicing.
The parts usedforeachMainC.B.A. are as follows.
2. SAFETY PRECAUTIONS
GENERALGUIDELINES
1. IMPORTANTSAFETY NOTICE
There are special components used inthisequipment which are
important for safety. These parts are marked byinthe
SchematicDiagrams, CircuitBoard Layout, Exploded Viewsand
Replacement Parts List. Itisessential that these critical parts
shouldbe replaced with manufacturer’sspecified parts to prevent
shock, fire or other hazards. Donot modifythe original design
without permission of manufacturer.
2. AnIsolation Transformer shouldalwaysbe used during the
servicing of VCR whose chassisisnot isolated from the AC power
line. Use atransformer of adequate power rating as thisprotects
the technician from accidents resulting inpersonal injuryfrom
electrical shocks. Itwill also protect VCR from being damaged by
accidental shorting that mayoccur during servicing.
3. When servicing, observe the original lead dress. Ifashort circuit
isfound, replace all parts which have been overheated or
damaged bythe short circuit.
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4. After servicing, see to itthat all the protective devices such as
insulation barriers, insulation papers shields are properly
installed.
5. After servicing, make the following leakage current checks to
prevent the customer from being exposed to shock hazards.
LEAKAGE CURRENTCOLD CHECK
1. Unplug the AC cord and connect ajumper between the two
prongs on the plug.
2. Measure the resistance value, with an ohmmeter, between the
jumpered AC plug and each exposed metalliccabinet part on the
equipment such as screwheads, connectors, control shafts, etc.
When the exposed metallicpart has areturn path to the chassis,
the reading shouldbe between 1M and 5.2M . When the
exposed metal does not have areturn path to the chassis, the
reading must be infinity.
LEAKAGE CURRENTHOTCHECK
(See figure 1.)
1. Plug the AC cord directlyinto the AC outlet. Donot use an
isolation transformer for thischeck.
2. Connect a1.5k , 10 Wresistor, inparallel with a0.15 F
capacitor, between each exposed metallicpart on the set and a
good earth ground, as showninfigure 1.
3. Use an AC voltmeter, with 1k /Vor more sensitivity, to measure
the potential across the resistor.
4. Check each exposed metallicpart, and measure the voltage at
each point.
5. Reverse the AC plug inthe AC outlet and repeat each of the above
measurements.
6. The potential at anypoint shouldnot exceed 0.75 VRMS. A
leakage current tester (Simpson Model 229 or equivalent) maybe
used to make the hot checks. Leakage current must not exceed 1/
2mA. Incase ameasurement isoutside of the limits specified,
there isapossibilityof ashock hazard, and the equipment should
be repaired and rechecked before itisreturned to the customer.
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Figure 1
3. PREVENTION OF ELECTRO-STATIC DISCHARGE
(ESD) TO ELECTROSTATICALLY SENSITIVE (ES)
DEVICES
Some semiconductor(solidstate) devices canbe damagedeasilybystatic electricity. Such
components commonlyare calledElectrostaticallySensitive (ES) Devices. Examples of typical
ES devices are integratedcircuits, some field-effect transistors and semiconductor"chip"
components. The following techniques shouldbe usedtohelpreduce the incidence of
component damage causedbyelectrostatic discharge (ESD).
1. Immediatelybefore handling anysemiconductor component or
semiconductor-equipped assembly, drainoff anyESDon your
bodybytouching aknownearth ground. Alternatively, obtainand
wear acommerciallyavailabledischarging ESDwrist strap, which
shouldremove electrostaticcharge for potential shock reasons
prior to applying power to the unitunder test.
2. After removing an electrical assemblyequipped with ES devices,
place the assemblyon aconductive surface such as aluminum
foil, to prevent electrostaticcharge buildup or exposure of the
assembly.
3. Use onlyagrounded-tipsoldering iron to solder or unsolder ES
devices.
4. Use onlyan antistaticsolder removal device. Some solder
removal devices not classified as "antistatic(ESDprotected)" can
generate electrical charge sufficient to damage ES devices.
5. Donot use freon-propelled chemicals. These can generate
electrical charges sufficient to damage ES devices.
6. Donot remove areplacement ES device from its protective
package until immediatelybefore you are readyto install it. (Most
replacement ES devices are packaged with leads electrically
shorted together byconductive foam, aluminum foil or
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comparableconductive material).
7. Immediatelybefore removing the protective material from the
leads of areplacement ES device, touch the protective material to
the chassisor circuitassemblyinto which the device will be
installed.
CAUTION:Besure no power isapplied to the chassisor circuit,
and observe all other safetyprecautions.
8. Minimize bodilymotions when handling unpackaged replacement
ES devices. (Otherwise harmless motion such as the brushing
together of your clothes fabricor the lifting of your foot from a
carpeted floor can generate staticelectricity(ESD)sufficient to
damage an ES device).
"NOTE toCATV systeminstaller:
This reminderis providedtocall the CATV systeminstaller’s attention toArticle 820-22 of the
NEC that provides guidelines forpropergrounding and, inparticular, specifies that the cable
ground shall be connectedtothe grounding systemof the building, as close tothe point of
cable entryas practical."
4. OPERATION GUIDE
5. SERVICE NOTES (PLEASE READ)
5.1. SERVICENOTES
5.1.1. SIMPLIFIED FAULT FINDING DATA
SimplifiedSelf-Diagnostic Systemfacilitates finding the cause of the fault. A 4 digit fault code
will be displayedinF.I.P.
The SimplifiedFault finding data is storedinthe MemoryIC (IC6005). This data is clearedafterit
is displayed, and thenthe POWER button is pressedback on.
1. With power turned off, press VCR/TV button on VCR (for over 3
seconds ifVCR isnot inshut off condition).
Fig. 1-1
2. Faultcode (4 digitnumber) will be displayed inF.I.P. as shown.
Fig. 1-2
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Fig. 1-3
Fig. 1-4
Fig. 1-5
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Fig. 1-6
3. Whilepressing VCR/TV button on VCR with power turned off,
press anyoperation button on either VCR, or remote to detect that
akeyhas been pressed.
The 1st digitchanges to "0" onlywhen keyisdetected.
Fig. 1-7
4. When 1to 4listed inLock code occurs, Lock data will be stored in
the EEPROMIC(Current data, Last Lock data, and the Last Lock
data before last). Lock data displayed inF.I.P. can be changed by
pressing CH DOWNbutton.
Fig. 1-8
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Note:
1. Lock data will be kept after the AC Cord isunplugged.
2. When 1to 4listed inLock code occurs for the first time, the VCR
does not go into VCR shut-off condition. Ifitoccurs againwithina
minute, the VCR goes into VCR shut-off condition. Then, the VCR
stops and all VCR function buttons except for power become non-
operational.
5.1.2. USAGE SCREEN MODE
Function displayedon the TV monitor:
-the total elapsed "Power on" time (indays)
-the total elapsed "Cylinder rotation" time (inhours)
1. With power turned on and no cassette, press VCR/TV button on
VCR and 7keyon remote together.
The USAGESCREENwill be displayed on the TV Monitor.
Fig. 3
Note:
1. After replacing the Cylinder Unit, press COUNTERRESET button
on remote inthismode. OnlyTotal elapsed "Cylinder rotation"
time (inhours) will be cleared to 0.
2. To release from Usage Screen Mode, press anyoperation button
on VCR or insert acassette tape inthismode. The VCR will return
to normal operation mode.
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5.1.3. EEPROM IC (IC6005), MAIN C.B.A. REPLACEMENTNOTE
Afterreplacing EEPROM IC (IC6005) orMainC.B.A., be sure toperform the "PG SHIFTER
ADJUSTMENT" inELECTRICALADJUSTMENTprocedures.
5.1.4. SERVICE POSITION
5.1.4.1. Service Position
CAUTION:
HOTCIRCUIT(Primarycircuit) exists on the MainC.B.A.
Use extreme care to prevent accidental shock when servicing.
5.1.4.1.1. Service Position (1)
Fig. 4-1
5.1.4.1.2. Service Position (2)
Fig. 4-2
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Note:
1. Itispossiblethat the S-Tab SW. maynot work correctlyinService
Position (2). (Recording can not be done). Inthiscase, short the S-
Tab SW. Pins on the foil side of the MainC.B.A. to turn thisSW.
on. Fig. 4-3
2. Place the tape between the Cassette UpAss’yand MainC.B.A. to
get astability.
3. When disassembling/assembling, refer to "CABINET SECTION"in
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DISASSEMBLY/ASSEMBLY PROCEDURES.
5.1.5. HOTCIRCUIT
Primarycircuit exists on the MainC.B.A.
This circuit is identifiedas "HOT" on the C.B.A. and inthe Service Manual. Use extreme care to
prevent accidental shock whenservicing.
5.1.6. SERVICE MODE
Inordertoinhibit detection of the Supply& Takeup PhotoTransistors, Reel Sensor, and
CylinderLock, press and holdVCR/TV button and CH DOWN buttons on VCR togetherover5
seconds inpoweroff condition.
Fig. 5-1
The powercomes on and the unit goes intoservice mode.
Inthis mode, Mechanismmovement canbe confirmed. Whenremoving Cassette UpAss’y, it
canbe confirmedwithout a cassette.
To release fromthis mode, press POWER button off ordisconnect AC Plug.
5.1.7. TRACKING CENTER MODE (TRACKING FIX ATCENTER)
Insert the Cassette tape. Set the unit intoService Mode. Playback the Cassette tape. Press
PLAY button inPlayback mode. "TRACKING CENTER" will be displayedon the TV monitor.
Inthis mode, the tracking is fixedat center. (Autotracking and manual tracking functions are
not operational.)
Fig. 5-2
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To release fromthis mode, press PLAY orSTOP button.
5.1.8. CAUTION FOR INSTALLATION OFFRONTPANELASS’Y
CAUTION:
Opener Lever maybe damaged when Front Panel Ass’yisinstalled,
with Cassette Door-Lidof Front Panel Ass’yand Opener Lever of
Cassette UpAss’yset incorrectly.
Install the Front Panel Ass’yas follows:
1. Swing the Cassette Door-Lidall the wayopen until the Cassette
Door tab clears the Opener Lever.
2. Make sure that all locking tabs are aligned properly. Then, press
the Front Panel straight in.
Fig. 6
5.1.9. METHOD FOR LOADING/UNLOADING OFMECHANISM
5.1.9.1. (Manual Method)
Turnthe Loading Gearclockwise (forloading) orcounterclockwise (forunloading) using
needlenose pliers etc.
Note:
Donot use thismethod ifMechanism isjammed or locked.
Fig. 7-1
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5.1.9.2. (Electrical Method)
Apply+10.0 V DC PowerSupplytothe Loading Motorterminals.
Loading
DC + toPortion "a," DC - toPortion "b"
Unloading
DC - toPortion "a," DC + toPortion "b"
CAUTION:
Before applying DC Power Supply, be sure to cut the Motor Leads
with acutter, etc.
Otherwise, the Loading Motor Drive IC(IC2501) maybe damaged.
When reconnecting the Motor Leads, solder at below / 320 °Cfor
less than 3seconds. Fig. 7-2
Whenloading without a cassette, pushPortion "a" on the HolderUnit of Cassette UpAss’yso
that the Leverclearthe First Taband Second Tab.
Fig. 7-3
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5.1.10. HOW TO REMOVE A JAMMED TAPE
CAUTION:
Wiper Arm Unitmaybe damaged or its spring maybe out of place
when the jammed tape isremoved byforce.
Remove a jammedtape as follows:
5.1.10.1. Manual Method
Whena tape jamis encountered, check the tape loading condition and use the following
procedure toremove a tape jam.
Fig. 8-1
Method -1:
1. Move the Pinch Roller Unitout byunhooking the Pinof Pinch Arm
Unitso that the Pinch Roller isseparated from the Capstan Rotor
Unitshaft. Fig. 8-2
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2. Remove the tape from the tape path.
3. Rewind the tape into the cassette byrotating the Center Clutch
Unitcounterclockwise.
4. Unhook Spring (A)of the Drive Rack Arm.
5. Remove Screw (A).
6. Lift the Cassette UpAss’y. Whilepulling the Cassette UpAss’y
out far enough so that itclears the Drive Rack Arm, slide the Drive
Rack Unitas indicated bythe arrow to remove the cassette tape
from the Cassette UpAss’y.
7. Check the cause of mechanical troubleand repair.
Fig. 8-3
Method -2:
1. Rotate Loading Motor counterclockwise with needlenose pliers,
etc. so that the Pinch Roller isseparated from the shaft of the
Capstan Rotor Unit.
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2. Perform Step 2through Step 7of Method -1.
Method -3:
1. Perform Step 2through Step 7of Method -1.
Note:
After repairing mechanical trouble, make sure that all gear
alignments are correct, especiallythe Wiper Arm Unitand Drive
Rack Unitof Cassette UpAss’y. (Refer to "EJECT Position
Confirmation"inDISASSEMBLY/ASSEMBLY PROCEDURES.)
5.1.10.2. Electrical Method
Electrical method canonlybe performedwhenthe mechanismis movedbyrotating the Loading
Gear.
CAUTION:
1. Before applying DC Power Supply, be sure to cut the Motor Leads
with acutter, etc.
Otherwise, the Loading Motor Drive IC(IC2501) maybe damaged.
When reconnecting the Motor Leads, solder at below / 320 °Cfor
less than 3seconds.
2. Ifloading does not start inapprox. 2seconds after DC Power
Supplyisapplied, DO NOTcontinue to applyDC Power Supply.
Instead, perform "Manual Method."
1. Besure to cut the Motor Leads with acutter, etc.
2. Apply+10.0VDC Power Supplyto the Loading Motor terminals.
3. When the Loading Posts reach the fullyunloaded position,
remove the Power Supply. Fig. 9
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4. Rewind the tape into the cassette byturning the Center Clutch
Unitcounterclockwise.
5. Eject the cassette byapplying +10.0VDC Power Supplyagain.
5.1.11. BLACK SCREWS ON THE CHASSIS
Black Screws are usedon the MechanismChassis toidentifyscrews that require adjustment.
5.1.12. HOW TO RESETALL VCR MEMORY FUNCTIONS
To reset (clear) the select language, channel autoset and set clock functions totheirinitial
poweron condition (poweron, no cassette inserted), holddownthe PLAY and CH UP buttons
on the unit togetherformore than5 seconds.
Powerwill shut off.
5.1.13. HOW TO CONFIRM AUTO CLOCK SETFEATURE
1. Connect an RFcablefrom the output of one unitto the input of
the test unit.
2. Select corresponding RFchannels.
3. Playback arecording of P.B.S. channel including clock set data
and confirm thisfeature.
5.1.14. VARIABLE VOLTAGE ISOLATION TRANSFORMER
AnIsolation Transformershouldalways be usedduring the servicing of VCR whose chassis is
not isolatedfromthe AC powerline. Use a transformerof adequate powerrating as this
protects the technicianfromaccidents resulting inpersonal injuryfromelectrical shocks. It will
alsoprotect VCR frombeing damagedbyaccidental shorting that mayoccurduring servicing.
Also, whentroubleshooting the above type of PowerSupplyCircuit, a variable isolation
transformeris requiredinordertoincrease the input voltage slowly.
5.1.15. SPECIALNOTE
All integratedcircuits and manyothersemiconductordevices are electrostaticallysensitive and
therefore require the special handling techniques describedunderthe
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"ELECTROSTATICALLY SENSITIVE (ES) DEVICES" section of this service manual.
5.1.16. REPLACEMENTPROCEDURE FOR LEADLESS (CHIP) COMPONENTS
The following procedures are recommendedforthe replacement of the leadless components
usedinthis unit.
1. Preparation for replacement
A. Soldering Iron
Use apencil-type soldering iron that uses less than 30 watts.
B. Solder
EutecticSolder (Tin63 %, Lead 37 %)isrecommended.
C. Soldering time
Donot applyheat for more than 4seconds.
D. Preheating
Leadless capacitor must be preheated before installation. -(266
°F ~ 302 °F)
(130 °C~150 °C)for about 2minutes.
Note:
A. Leadless components must not be reused after removal.
B. Excessive mechanical stress and rubbing of the component
electrode must be avoided.
2. Removing the leadless component
Grasp the leadless component bodywith tweezers and alternately
applyheat to both electrodes. When the solder on both electrodes
ismelted, remove the leadless component with atwisting motion.
Note:
A. Donot attempt to lift the component off the board until the
component iscompletelydisconnected from the board bya
twisting action.
B. Becareful not to break the copper foil on the printed circuit
board. Fig. 10-1
3. Installing the leadless component
A. Presolder the contact points on the circuitboard.
Fig. 10-2
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B. Press the part downward with tweezers and solder both
electrodes as shownbelow.Fig. 10-3
Note:
Donot glue the replacement leadless component to the circuit
board.
5.1.17. MODELNO. IDENTIFICATION MARK
Use Marks showninthe chart belowtodistinguishthe different models includedinthis Service
Manual.
5.1.18. PV-V4621 REPLACEMENTNOTE
There are 2 types of MainC.B.A. (E10) forPV-V4621.
VEPS6073HA is usedinearlyproducts and has beenchangedtoVEPS6073HC on running
change basis inlaterproducts. Whenreplacing MicrocontrollerIC (IC6001) orEEP ROM IC
(IC6005), be sure toconfirm whichMainC.B.A. is usedforthe unit you are servicing.
The parts usedforeachMainC.B.A. are as follows.
5.2. IC, TRANSISTORAND CHIPPARTINFORMATION
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6. DISASSEMBLY/ASSEMBLY PROCEDURES
6.1. CABINET SECTION
6.1.1. DisassemblyFlowchart
Perform all disassemblyprocedures inthe orderdescribedinthe "DisassemblyFlowchart"
shownbelow. Whenreassembling, use the reverse procedure.
CAUTION:
Disconnect AC plug before disassembly.
Fig. D1
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