Panasonic SB-WA933 User manual

ORDERNO. MD0508312C1
A6
Active Subwoofer System
SB-WA933P
Colour
(S)...Silver Type
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SPECIFICATIONS
Specification
Activesubwoofer
Type 1way, 2speaker system (Bass
reflex)
Speaker unit(s) Impedance 4
1. Woofer 15 cm (5-7/8”) Conetype
2. Woofer 15 cm (5-7/8”) Conetype
Output sound pressure 84 dB/W(1.0m)
Frequencyrange 34 Hz-220 Hz (-16 dB)
38 Hz-190 Hz (-10 dB)
Dimensions(WxH xD) 285 mm x402 mm x520 mm
(11-7/32” x15-13/16” x20-15/32”)
Mass 15 kg(33.1lbs)
General
Power supply AC 120V, 60Hz
Power consumption 390 W
System: SC-HT933(P) MusicCenter: SA-HT933(P)
SatelliteSpeakers: SB-HT920(P)
ActiveSubwoofer: SB-WA933(P)
Note:
Specificationsare subject tochangewithout notice.
Mass and dimensionsare approximate.
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2005 Matsushita ElectricIndustrial Co. Ltd.. All rights reserved.
Unauthorized copying and distribution isaviolation of law.
1. Safety Precautions
1.1. GENERALGUIDELINES
1. When servicing, observe the original lead dress. Ifashort circuit
isfound, replace all parts which have been overheated or
damaged bythe short circuit.
2. After servicing, ensure that all the protective devices such as
insulation barriers, insulation papers shields are properly
installed.
3. After servicing, check for leakage current to prevent from being
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exposed to shock hazards.
(This “SafetyPrecaution” is appliedonlyinU.S.A.)
1. Before servicing, unplug the power cord to prevent an electric
shock.
2. When replacing parts, use onlymanufacturer’srecommended
components for safety.
3. Check the condition of the power cord. Replace ifwear or damage
isevident.
4. After servicing, be sure to restore the lead dress, insulation
barriers, insulation papers, shields, etc.
5. Before returning the serviced equipment to the customer, be sure
to make the following insulation resistance test to prevent the
customer from being exposed to ashock hazard.
1.1.1. LEAKAGE CURRENTCOLD CHECK
1. Unplug the AC cord and connect ajumper between the two
prongs on the plug.
2. Using an ohmmeter measure the resistance value, 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 5.2 . / When the
exposed metal does not have areturn path to the chassis, the
reading must be . Fig. 1
1.1.2. LEAKAGE CURRENTHOTCHECK (See Figure1.)
1. Plug the AC cord directlyinto the AC outlet. Donot use an
isolation transformer for thischeck.
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2. Connect a1.5k , 10 watts resistor, inparallel with a0.15 F
capacitors, between each exposed metallicpart on the set and a
good earth ground such as awater pipe, as showninFigure 1.
3. Use an AC voltmeter, with 1000 ohms/voltor 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 volts RMS. A
leakage current tester (Simpson Model 229 or equivalent) maybe
used to make the hot checks, leakage current must not exceed 1/2
milliamp. Shouldthe measurement isoutside of the limits
specified, there isapossibilityof ashock hazard, and the
equipment shouldbe examine and rechecked before itisreturned
to the customer.
1.1.3. Caution forfuse replacement
2. Handling the Lead-free Solder
2.1. About lead free solder (PbF)
Distinction of PbF P.C.B. :
P.C.B.s (manufactured) using leadfree solderwill have a PbF stampon the P.C.B.
Caution:
-Pb free solder has ahigher melting point than standard solder:
Typicallythe melting point is50 -70°F (30 -40°C)higher. / Please
use ahigh temperature soldering iron. Incase of the soldering
iron with temperature control, please set itto 700 ± 20°F (370 ±
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10°C).
-Pb free solder will tend to splash when heated too high (about
1100°F/600°C).
-When soldering or unsoldering, please completelyremove all of
the solder on the pins or solder area, and be sure to heat the
soldering points with the Pb free solder until itmelts enough.
3. Before Repair and Adjustment
Disconnect AC power, discharge PowerSupplyCapacitors C601 ~ C604 through a 10 , 1 W
resistortoground.
DO NOTSHORT-CIRCUITDIRECTLY (witha screwdriverblade, forinstance), as this may
destroysolidstate devices.
Afterrepairs are completed, restore powergraduallyusing a variac, toavoidovercurrent.
Current consumption at AC 120V, 60Hz inNO SIGNALmode (volume at min) shouldbe ~1000
mA .
4. Protection Circuitry
The protection circuitrymayhave operatedif eitherof the following conditions are noticed:
-Nosound isheard when the power isturned on.
-Sound stops during aperformance.
The function of this circuitryis toprevent circuitrydamage if, forexample, the positive and
negative speakerconnection wires are
“shorted”, orif speakersystems withanimpedance less thanthe indicatedratedimpedance of
the amplifierare used.
If this occurs, followthe procedure outlines below:
1. Turn off the power.
2. Determine the cause of the problem and correct it.
3. Turn on the power once againafter one minute.
Note :
Whenthe protection circuitryfunctions, the unit will not operate unless the poweris first turned
off and thenon again.
5. Connection of the Speaker Cables
-Besure to connect speaker cables before connecting the AC
power supplycord.
-The load impedance of anyspeaker used with thisunitmust be 4 .
-Besure to connect the cablefrom the right speaker to the right
terminal and the cablefrom the left speaker to the left terminal.
1. Stripoff the outer covering, and twist the center conductor. Make
sure the bare ends of the wires are not unravelled. (Iftheyare,
twist them tight again.)
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2. Insert the wire to the rear panel of the unitand close the lever.
6. Disassembly Procedure
“ATTENTION SERVICER”
Some chassis components mayhave sharpedges.
Be careful whendisassembling and servicing.
1. Thissection describes procedures for checking the operation of
the major printed circuitboards and replacing the main
components.
2. For reassemblyafter operation checks or replacement, reverse
the respective procedures.
Special reassemblyprocedures are described onlywhen required.
3. Select items from the following index when checks or
replacement are required.
6.1. Disassemblyflow chart
The following chart is the procedure fordisassembling the casing and inside parts forinternal
inspection whencarrying out the servicing.
To assemble the unit, reverse the steps showninthe chart below.
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6.1.1. Disassemblyof the WooferSpeakers
6.1.2. Disassemblyof the PowerAmpUnit
6.2. Disassemblyof the Speaker Unitand Checking of the P.C.B.
6.2.1. Disassemblyof the Front Panel Unit
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Step1: Slot ina steel rulerintothe holes togive a gapbetweenthe Front Panel unit and the
speakercabinet assemblyunit as arrowshown.
Steps 2: Slot a piece of wood chipinbetweenthe Front Panel unit and the steel ruleras arrow
shown.
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Step3: Use the screwdriverslightlylift up the Front Panel unit as arrowshown.
Note:
Be careful withthe bosses whichare gluedtothe unit.
Step4: Remove the Front Panel unit fromthe speakercabinet assemblyunit as arrowshown.
-Assemblyof the Front Panel unit.
Step 1: Clean up the remaining glue at the 8boss points and
replace with the normal glue.
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Step 2: Replace the Front Panel unitfirmlyback to the speaker
cabinet assemblyunit.
6.2.2. Disassemblyof WooferSpeakerUnit 1
FollowStep(1) toStep(4) describedinsection 6.2.1.
Step1: Remove 4 screws fromthe Woofer1.
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Step2: Remove the Woofer1 bydetaching the (+) and (-) wires.
6.2.3. Disassemblyof WooferSpeakerUnit 2
FollowStep(1) toStep(4) describedinsection 6.2.1.
Step1: Remove 4 screws fromthe Woofer2.
Step2: Remove the Woofer2 bydetaching the (+) and (-) wires.
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6.2.4. Disassemblyof the PowerAmpUnit
Step1: Remove 7 screws fromthe bottomof the speakercabinet assemblyunit.
Step2: Remove 3 screws fromthe rearpanel.
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Step3: Slightlypull out the PowerAmpunit as arrowshown.
Step4: Disconnect the connectorCN604 and pull out the entire PowerAmpunit.
6.2.5. Disassemblyof the RearPanel and Fan Unit
FollowStep(1) toStep(4) describedinsection 6.2.4.
Steps 1 and 2: Remove 7 screws fromthe rearpanel.
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Step3: Disconnect the connectorCN507 todetachthe rearpanel.
Step4: Remove 2 screws fromthe rearpanel.
Step5: Laythe rearpanel flat and remove the fanunit as arrowshown.
6.2.6. Disassemblyand checking of the AmplifierP.C.B. and AC Inlet P.C.B.
FollowStep(1) toStep(4) describedinsection 6.2.4.
FollowStep(1) toStep(3) describedinsection 6.2.5.
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Step1: Check bothAmplifierP.C.B. and AC Inlet P.C.B.
6.2.7. Disassemblyand checking of the PowerP.C.B. and TransformerP.C.B.
FollowStep(1) toStep(4) describedinsection 6.2.4.
FollowStep(1) toStep(3) describedinsection 6.2.5.
Steps 1 and 2: Remove 4 screws.
Step3: Flipthe PowerP.C.B. as shownforchecking bothPowerP.C.B. and TransformerP.C.B.
6.2.8. Replacement of PowerICsand Transistors
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FollowStep(1) toStep(4) describedinsection 6.2.4.
FollowStep(1) toStep(3) describedinsection 6.2.5.
Step1: Disconnect the connectorCP502.
Step2: Remove the AC Inlet P.C.B. bypulling the P.C.B. support clawas arrowshown.
Step3: Desolderthe terminals of IC601, Transistors Q601 and Q602.
Step4: Disconnect the connectors CN601, CN602 and CN603 and remove the AmplifierP.C.B.
Step5: Remove 4 screws.
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Step6: Remove 2 screws and the transistorholders.
Step7: Flipthe PowerP.C.B. as showntodesolderthe terminals of the PowerIC501,
Transistors Q511 and Q512.
7. Voltage Measurement and Waveform Chart
7.1. Voltage Measurement
7.1.1. AC INLETP.C.B.
7.1.2. POWER P.C.B.
7.1.3. AMPLIFIER P.C.B.
7.2. Waveform
8. Block Diagram
9. Notes of Schematic Diagram
(All schematic diagrams maybe modifiedat anytime withthe development of the new
technology)
Note:
-The voltage value and waveforms are the reference voltage of this
unitmeasured byDC electronicvoltmeter (high impedance) and
oscilloscope on the basisof chassis. Accordingly, there mayarise
some error involtage values and waveforms depending upon the
internal impedance of the tester or the measuring unit.
-Importance safetynotice :
Components identified bymark have special characteristics
important for safety. Furthermore, special parts which have
purposes of fire-retardant (resistors), high-qualitysound
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(capacitors), low-noise (resistors), etc. are used. When replacing
anyof components, be sure to use onlymanufacturer's specified
parts showninthe parts list.
Caution !
IC, LSI and VLSI are sensitive tostatic electricity.
Secondarytrouble canbe preventedbytaking care during repair.
-Cover the parts boxes made of plastics with aluminium foil.
-Put aconductive mat on the work table.
-Ground the soldering iron.
-Donot touch the pins of IC, LSI or VLSI with fingers directly.
10. Schematic Diagram
10.1. Power Circuit
10.2. AC Inlet Circuitand Transformer Circuit
10.3. Amplifier Circuit
11. Printed Circuit Board
11.1. Power P.C.B.
11.2. AC Inlet P.C.B. and Transformer P.C.B.
11.3. Amplifier P.C.B.
12. Wiring Connection Diagram
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13. Illustration of IC’s, Transistors and Diodes
14. Parts Location and Replacement Parts List
Notes:
-Important safetynotice:
Components identified bymark have special characteristics
important for safety.
Furthermore, special parts which have purposes of fire-retardant
(resistors), high-qualitysound (capacitors), low noise (resistors),
etc are used.
When replacing anyof these components, be sure to use only
manufacturer’sspecified parts showninthe parts list.
-The parenthesized indications inthe Remarks columns specifythe
areas or colour. (Refer to the cover page for area or colour)
Parts without these indications can be used for all areas.
-Capacitor values are inmicrofarads ( F) unless specified
otherwise, P= Pico-farads (pF), F= Farads.
-Resistance values are inohms, unless specified otherwise, 1K=
1,000 (OHM).
-The marking (RTL) indicates that the Retention Time islimited for
thisitems. After the discontinuation of thisassemblyin
production, the item will continue to be availablefor aspecific
period of time. The retention period of aavailabilityisdependent
on the type of assembly, and inaccordance with the laws
governing part and product retention. After the end of thisperiod,
the assemblywill no longer be available.
-[M] Markings inthe Remarks columns indicates parts supplied by
PAVCSG.
14.1. Cabinet
14.1.1. Cabinet PartsLocation
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