Panasonic SB-WA920PP User manual

ORDERNO. MD0403057C1
A6
ActiveSubwooferSystem
SB-WA920PP
Colour
(S)...SilverType
SPECIFICATIONS
Specification
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Activesubwoofer
Type 1way, 1speakersystem (Bass
reflex)
Speakerunit Impedance 4
Woofer 20 cm (7-7/8”)Conetype
Outputsound pressure 84 dB/W (1.0m)
Frequencyrange 34 Hz-220 Hz(-16 dB)
38 Hz-190 Hz(-10 dB)
Dimensions(W xHxD) 285 x418 x475 mm
(11-7/32”x16-15/32”x18-11/16”)
Mass 15 kg (33 lb.)
General
Powerconsumption 390V
Powersupply AC120V, 60Hz
Note:
Specificationsaresubjectto changewithoutnotice.
Mass and dimensionsareapproximate.
SB-HT920P-S consistsof:
SB-PF920P-S x2, SB-PS920P-S x2and SB-PC920P-S x1
System :SC-HT920 (P) MusicCenter:SA-HT920 (P)
SatelliteSpeakers:SB-HT920 (P)
ActiveSubwoofer:SB-WA920 (PP)
System :SC-HT920 (PC) MusicCenter:SA-HT920 (PC)
SatelliteSpeakers:SB-HT920 (P)
ActiveSubwoofer:SB-WA920 (PP)
1. SafetyPrecautions
1.1. GENERALGUIDELINES
1. Whenservicing, observetheoriginal leaddress. Ifashortcircuit
isfound, replace all parts whichhavebeenoverheatedor
damagedbytheshortcircuit.
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2. Afterservicing, see toitthat all theprotectivedevices suchas
insulation barriers, insulation papersshieldsareproperlyinstalled.
3. Afterservicing, make thefollowing leakagecurrentchecks to
preventthecustomerfrombeing exposedtoshock hazards.
(This“SafetyPrecaution”isappliedonlyinU.S.A.)
1. Beforeservicing, unplug thepowercordtopreventanelectric
shock.
2. Whenreplacing parts, use onlymanufacturer’srecommended
components forsafety.
3. Check thecondition ofthepowercord. Replace ifwearordamage
isevident.
4. Afterservicing, besuretorestoretheleaddress, insulation
barriers, insulation papers, shields, etc.
5. Beforereturning theservicedequipmenttothecustomer, besure
tomake thefollowing insulation resistance test topreventthe
customerfrombeing exposedtoashock hazard.
1.1.1. LEAKAGE CURRENTCOLDCHECK
1. Unplug theACcordand connect ajumperbetweenthetwoprongs
on theplug.
2. Measuretheresistance value, withanohmmeter, betweenthe
jumperedACplug and eachexposedmetalliccabinet parton the
equipmentsuchas screwheads, connectors, control shafts, etc.
Whentheexposedmetallicparthas areturnpathtothechassis,
thereading shouldbebetween1M and 5.2 . / Whenthe
exposedmetal does nothaveareturnpathtothechassis, the
reading must be . Fig. 1
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1.1.2. LEAKAGE CURRENTHOTCHECK (See Figure1.)
1. Plug theACcorddirectlyintotheACoutlet. Donotuse an
isolation transformerforthischeck.
2. Connect a1.5k , 10 watts resistor, inparallel witha0.15 F
capacitors, betweeneachexposedmetallicparton theset and a
good earthground suchas awaterpipe, as showninFigure1.
3. Use anACvoltmeter, with1000 ohms/voltormoresensitivity, to
measurethepotential across theresistor.
4. Check eachexposedmetallicpart, and measurethevoltageat
eachpoint.
5. Reverse theACplug intheACoutlet and repeat eachoftheabove
measurements.
6. Thepotential at anypointshouldnotexceed0.75 volts RMS. A
leakagecurrenttester(Simpson Model 229 orequivalent) maybe
usedtomake thehotchecks, leakagecurrentmust notexceed1/2
milliamp. Incase ameasurementisoutsideofthelimits specified,
thereisapossibilityofashock hazard, and theequipmentshould
berepairedand recheckedbeforeitisreturnedtothecustomer.
2. Handling the Lead-free Solder
2.1. Aboutleadfree solder(PbF)
Distinction ofPbF P.C.B. :
P.C.B.s(manufactured)using leadfree solderwill have aPbF stampon theP.C.B.
Caution:
-Pbfree solderhas ahighermelting pointthat standardsolder;
Typicallythemelting pointis50 -70°F(30 -40°C)higher. / Please
use ahigh temperaturesoldering iron. Incase ofthesoldering iron
withtemperaturecontrol, please set itto700 ±20°F(370 ±10°C).
-Pbfree solderwill tend tosplashwhenheatedtoo high (about
1100°F/600°C).
-Whensoldering orunsoldering, please completelyremoveall ofthe
solderon thepinsorsolderarea, and besuretoheat thesoldering
points withthePbfree solderuntil itmelts enough.
3. BeforeRepairand Adjustment
DisconnectACpower, dischargePowerSupplyCapacitorsC546, C547, C548, C549 through a10
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, 1Wresistor toground.
DONOTSHORT-CIRCUITDIRECTLY(withascrewdriverblade, for instance), as thismay destroy
solidstatedevices.
Afterrepairsarecompleted, restorepowergraduallyusing avariac, toavoidovercurrent.
Currentconsumption atAC120V, 60HzinNOSIGNALmodeshouldbe~1000 mA.
4. Protection Circuitry
Theprotection circuitrymay have operatedifeitherofthefollowing conditionsarenoticed:
-Nosound isheardwhenthepoweristurnedon.
-Sound stopsduring aperformance.
Thefunction ofthiscircuitryistopreventcircuitrydamageif, for example, thepositive and
negative speakerconnection wires are
“shorted”, or ifspeakersystemswithanimpedance less thantheindicatedratedimpedance of
theamplifierareused.
Ifthisoccurs, followtheprocedureoutlines below:
1. Turnoff thepower.
2. Determinethecause oftheproblemand correct it.
3. Turnon thepoweronce againafteroneminute.
Note:
Whentheprotection circuitryfunctions, theunitwill notoperateunless thepowerisfirstturned
off and thenon again.
5. Connection of the SpeakerCables
-Besuretoconnect speakercables beforeconnecting theACpower
supplycord.
-Theloadimpedance ofanyspeakerusedwiththisunitmust be4 .
-Besuretoconnect thecablefromtherightspeakertotheright
terminal and thecablefromtheleft speakertotheleft terminal.
1. Stripoff theoutercovering, and twist thecenterconductor. Make
surethebareendsofthewires arenotunravelled. (Iftheyare,
twist themtightagain.)
2. Insertthewiretotherearpanel oftheunitand close thelever.
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Notes :
-To preventdamagetocircuitry, nevershort-circuitpositive(+)and
negative(-) speakerwires.
-Besuretoconnect onlypositive(Copper)wires topositive(+)
terminalsand negative(Silver)wires tonegative(-) terminals.
6. DisassemblyProcedure
“ATTENTIONSERVICER”
Somechassiscomponentsmay have sharp edges.
Becareful whendisassembling and servicing.
1. Thissection describes procedures forchecking theoperation of
themajorprintedcircuitboardsand replacing themain
components.
2. Forreassemblyafteroperation checks orreplacement, reverse the
respectiveprocedures.
Special reassemblyprocedures aredescribedonlywhenrequired.
3. Select itemsfromthefollowing index whenchecks orreplacement
arerequired.
Contents
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-DisassemblyoftheSpeakerUnit
-MainComponentReplacementProcedures
6.1. Disassemblyflow chart
Thefollowing chartistheprocedurefor disassembling thecasing and insidepartsfor internal
inspection whencarrying outtheservicing.
Toassembletheunit, reverse thestepsshowninthechartbelow.
6.2. DisassemblyoftheSpeakerUnitand Checking oftheP.C.B.
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Step1:Remove all thescrews.
Step2:Remove thestand base.
Steps3&4:Remove all thescrewsfrom thebottom ofthespeakerunit.
Step5:Use theSteel Rulertoslotintotheholeofthebottom cabinetofspeaker.
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Step6:Use theWood ChiptoslotbetweentheNetFrameand theSteel Ruleras arrowshown.
Step7:Use theScrewdriverslightlylift up theNetFrameas arrowshown.
Step8:Take noteofthebosses whichgluedtotheunit.
-AssemblyofNet Frame.
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Cleanup all theglueatthe4Boss pointsand replace withthenormal glue.
Replace theNetFramefirmlyback intothecabinet.
Step9:Remove theNetFramefrom thecabinetofspeaker.
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