SBWA-730-GCP
n Active subwoofer
Type 1 way, 2 speaker system (Bass reflex)
Speaker unit(s) Impedance 4 Ω
1. Woofer 13 cm Cone type
2. Woofer 13 cm Cone type
Output sound pressure 80 dB/W (1.0 m)
Frequency range 40 Hz-220 Hz (-16 dB)
45 Hz-180 Hz (-10 dB)
Dimensions (W x H x D) 201.5 mm x 368.2 mm x 491.5 mm
Mass 11.3 kg
n General
Power supply AC 110V/127V/220-230V/240V,
50/60Hz
Power consumption 340 W
Power consumption
(Standby mode)
approx. 0.9 W
1 Safety Precautions
3
1.1. GENERAL GUIDELINES
3
2 Before Use
4
© 2005 Matsushita Electric Industrial Co. Ltd.. All
rights reserved. Unauthorized copying and
distribution is a violation of law.
SB-WA730GCP
Colour
(S)...Silver Type
Note :
Specifications are subject to change without notice.
Mass and dimensions are approximate.
n System : SC-HT730(GCP)
Music Center: SA-HT730(GCP)
Satellite Speakers: SB-HT730(P)
Active Subwoofer: SB-WA730(GCP)
n System : SC-HT730(PX)
Music Center: SA-HT730(PX)
Satellite Speakers: SB-HT730(P)
Active Subwoofer: SB-WA730(GCP)
3 Before Repair and Adjustment 4
4 Protection Circuitry
4
Active Subwoofer System
Specification
CONTENTS
Page Page
ORDER NO. MD0503056C3
5 Handling the Lead-free Solder 4
5.1. About lead free solder (PbF)
4
6 Connection of the Speaker Cables
5
7 Disassembly Procedure
6
7.1. Disassembly flow chart
7
7.2. Disassembly of the Speaker Unit and Checking of the
P.C.B.
8
8 Voltage Measurement and Waveform Chart
14
8.1. Voltage Measurement
14
8.2. Waveform
15
9 Block Diagram
16
10 Notes of Schematic Diagram
17
11 Schematic Diagram
18
11.1. Power Circuit
18
11.2. Transformer Circuit, AC Inlet Circuit and Voltage Selector
Circuit
20
12 Printed Circuit Board
21
12.1. Power P.C.B.
21
12.2. AC Inlet P.C.B., Transformer P.C.B. and Voltage Selector
P.C.B.
23
13 Wiring Connection Diagram
24
14 Illustration of IC 痴, Transistors and Diodes
25
15 Parts Location and Replacement Parts List
26
15.1. Cabinet
27
15.2. Electrical Parts List
30
15.3. Packing Materials & Accessories Parts List
32
15.4. Packaging
32
2
SB-WA730GCP
1 Safety Precautions
1.1. GENERAL GUIDELINES
1. When servicing, observe the original lead dress. If a short circuit is found, replace all parts which have been overheated or
damaged by the 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 exposed to shock hazards.
1.1.1. LEAKAGE CURRENT COLD CHECK
1. Unplug the AC cord and connect a jumper between the two prongs on the plug.
2. Using an ohmmeter measure the resistance value, between the jumpered AC plug and each exposed metallic cabine t part on
the equipment such as screwheads, connectors, control shafts, etc. When the exposed metallic part has a return path to the
chassis, the reading should be between 1MΩ and 5.2Ω.
When the exposed metal does not have a return path to the chassis, the reading must be .
Fig. 1
1.1.2. LEAKAGE CURRENT HOT CHECK (See Figure 1.)
1. Plug the AC cord directly into the AC outlet. Do not use an isolation transformer for this check.
2. Connect a 1.5kΩ, 10 watts resistor, in parallel with a 0.15µF capacitors, between each exposed metallic part on the set and a
good earth ground such as a water pipe, as shown in Figure 1.
3. Use an AC voltmeter, with 1000 ohms/volt or more sensitivity, to measure the potential across the resistor.
4. Check each exposed metallic part, and measure the voltage at each point.
5. Reverse the AC plug in the AC outlet and repeat each of the above measurements.
6. The potential at any point should not exceed 0.75 volts RMS. A leakage current tester (Simpson Model 229 or equivalent) may
be used to make the hot checks, leakage current must not exceed 1/2 milliamp. Should the measurement is outside of the limits
specified, there is a possibility of a shock hazard, and the equipment should be repaired and rechecked before it is returned to
the customer.
3
SB-WA730GCP
2 Before Use
Be sure to disconnect the mains cord before adjusting the voltage selector. Use a minus (-) screwdriver to set the voltage selector
(on the rear panel) to the voltage setting for the area in which the unit will be used.
(If the power supply in your area is 117V or 120V, set to the “127V” position.)
Note that this unit will be seriously damaged if this setting is not made correctly. (There is no voltage selector for some countries;
the correct voltage is already set.)
3 Before Repair and Adjustment
Disconnect AC power, discharge Power Supply Capacitors C546~C549 through a 10 Ω, 1 W resistor to ground.
DO NOT SHORT-CIRCUIT DIRECTLY (with a screwdriver blade, for instance), as this may destroy solid state devices.
After repairs are completed, restore power gradually using a variac, to avoid overcurrent.
Current consum ption at AC 100/110 V, 50/60 Hz in NO SIGNAL mode should be ~1180 mA.
Current consum ption at AC 230-240 V, 50 Hz in NO SIGNAL mode should be ~600 mA.
4 Protection Circuitry
The protection circuitry may have operated if either of the following conditions are noticed:
·
No sound is heard when the power is turned on.
·
Stops during a performance.
The function of this circuitry is to prevent circuitry damage if, for example, the positive and negative speaker connection wires are
“shorted”, or if speaker systems with an impedance less than the indicated rated impedance of the amplifier are used.
If this occurs, follow the procedure outlines below:
1. Turn off the power.
2. Determine the cause of the problem and correct it.
3. Turn on the power once again after one minute.
Note:
When the protection circuitry functions, the unit will not operate unless the power is first turned off and then on again.
5 Handling the Lead-free Solder
5.1. About lead free solder (PbF)
Distinction of PbF P.C.B. :
P.C.B.s (manufactured) using lead free solder will have a PbF stamp on the P.C.B.
Caution:
·
Pb free solder has a higher melting point than standard solder. Typically the melting point is 50 - 70°F (30 - 40°C) higher.
Please use a high temperature soldering iron. In case of the soldering iron with temperature control, please set it to 700 ± 20°F
(370 ± 10°C).
·
Pb free solder will tend to splash when heated too high (about 1100°F/600°C).
·
W hen soldering or unsoldering, please completely remove all of the solder on the pins or solder area, and be sure to heat the
soldering points with the Pb free solder until it melts enough.
4
SB-WA730GCP
6 Connection of the Speaker Cables
·
Be sure to connect speaker cables before connecting the AC power supply cord.
·
The load impedance of any speake r used with this unit must be 4Ω.
·
Be sure to connect the cable from the right speake r to the right terminal and the cable from the left speaker to the left terminal.
1. Strip off the outer covering, and twist the center conductor. Make sure the bare ends of the wires are not unravelled. (If they are,
twist them tight again.)
2. Insert the wire to the rear panel of the unit and close the lever.
5
SB-WA730GCP
Some chassis components may have sharp edges.
Be careful when disassembling and servicing.
7 Disassembly Procedure
“ATTENTION SERVICER”
1. This section describes procedures for checking the operation of the major printed circuit boards and replacing the
main components.
2. For reassembly after operation checks or replacement, reverse the respective procedures.
Special reassembly procedures are described only when required.
3. Select items from the following index when checks or replacement are required.
·
Disassembly of the Front Panel Unit
·
Disassembly of the Woofer 1
·
Disassembly of the Woofer 2
·
Disassembly of the Power Amp Unit
·
Disassembly of the Rear Panel and Fan Unit
·
Disassembly and checking of the AC Inlet P.C.B., Power P.C.B. and Transformer P.C.B.
·
Replace ment of Power IC and Transistor
6
SB-WA730GCP
7.1. Disassembly flow chart
The following chart is the procedure for disassembling the casing and inside parts for internal inspection when carrying out the
servicing.
To assemble the unit, reverse the steps shown in the chart below.
7.1.1. Disassembly of Front Panel Assembly
7.1.2. Disassembly of Rear Assembly
7
SB-WA730GCP
7.2.1. Disassembly of the Front Panel
Unit
Step 1: Slot in a steel ruler to give a gap between the Front
Panel Unit and the Subwoofer Cabinet Assembly as arrow
shown.
Steps 2: Slot a piece of wood chip in between the Front Panel
Unit and the steel ruler as arrow shown.
Step 3: Use the screwdriver to slightly lift up the Front Panel
Unit as arrow shown.
Note:
Be careful with the bosses which are glued to the Subwoofer
Cabinet Assembly.
Step 4: Remove the Front Panel Unit from the Subwoofer
Cabinet Assembly.
7.2. Disassembly of the Speaker Unit and Checking of the P.C.B.
8
SB-WA730GCP
·
Assembly of the Front Panel Unit.
Step 1: Clean up all the glue at the 6 Boss points and
replace with the normal glue.
Step 2: Replace the Front Panel Unit firmly back to the
cabinet.
7.2.2. Disassembly of the Woofer 1
Follow Step (1) to Step (4) described in section 7.2.1.
Step 1: Remove 4 screws from the Woofer 1.
Step 2: Remove the Woofer 1 by detaching the (+) and (-)
wires.
7.2.3. Disassembly of the Woofer 2
9
SB-WA730GCP
Step 1: Remove 4 screws from the Woofer 2.
Step 2: Remove the Woofer 2 by detaching the (+) and (-)
wires.
7.2.4. Disassembly of the Power Amp
Unit
Step 1: Lay the speake r unit as shown. Remove 6 screws from
the bottom of the woofer unit.
Step 2: Remove 3 screws from the rear panel.
Step 3: Pull out the Power Amp Unit slightly as shown.
Step 4: Disconnect connector CN506.
10
SB-WA730GCP
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