ORDER NO. MD0503099C3
Active Subwoofer System
SB-WA930EE
Colour
(S)... Silver Type
Specification
n Active subwoofer |
|
|
|
Type |
1 way, 2 speaker system, Bass reflex |
Note : |
|
Speaker unit(s) |
|
Specifications are subject to change without notice. |
|
1. Woofer |
15 cm Cone type |
Mass and dimensions are approximate. |
|
2. Woofer |
15 cm Cone type |
|
|
Output sound pressure |
84 dB/W (1.0 m) |
n System : SC-HT930(EE) |
Music Center: SA-HT930(EE) |
Frequency range |
34 Hz-220 Hz (-16 dB) |
|
Satellite Speakers: SB-HT880(EB) |
|
38 Hz-190 Hz (-10 dB) |
|
Active Subwoofer: SB-WA930(EE) |
Dimensions (W x H x D) |
202 x 410 x 500 mm |
|
|
Mass |
13.7 kg |
|
|
n General |
|
|
|
Power consumption |
390 W |
|
|
Power supply |
AC 230V, 50Hz |
|
|
Power consumption (standby |
0.7 W |
|
|
mode) |
|
|
|
CONTENTS
|
|
Page |
|
|
|
Page |
1 |
Safety Precautions |
3 |
|
2.1. About lead free solder (PbF) |
4 |
|
|
1.1. GENERAL GUIDELINES |
3 |
3 |
Before Repair and Adjustment |
4 |
|
2 |
Handling the Lead-free Solder |
4 |
4 |
Protection Circuitry |
4 |
|
|
|
|
|
|
|
|
|
|
|
|
|
© 2005 Matsushita Electric Industrial Co. Ltd.. All |
|
|
|
|
|
|
rights reserved. Unauthorized |
copying and |
|
|
|
|
|
distribution is a violation of law. |
|
|
|
|
|
|
|
|
SB-WA930EE
5 |
Connection of the Speaker Cables |
5 |
|
10.3. Amplifier Circuit |
21 |
6 |
Disassembly Procedure |
6 |
11 |
Printed Circuit Board |
22 |
|
6.1. Disassembly flow chart |
6 |
|
11.1. Power P.C.B. |
22 |
|
6.2. Disassembly of the Speaker Unit and Checking of the |
|
|
11.2. AC Inlet P.C.B. and Transformer P.C.B. |
24 |
|
P.C.B. |
8 |
|
11.3. Amplifier P.C.B. |
25 |
7 |
Voltage Measurement and Waveform Chart |
14 |
12 |
Wiring Connection Diagram |
26 |
|
7.1. Voltage Measurement |
14 |
13 |
Illustration of ICs, Transistors and Diodes |
27 |
|
7.2. Waveform Chart |
15 |
14 |
Parts Location and Replacement Parts List |
28 |
8 |
Block Diagram |
16 |
|
14.1. Cabinet |
29 |
9 |
Notes of Schematic Diagram |
17 |
|
14.2. Electrical Parts List |
32 |
10 |
Schematic Diagram |
18 |
|
14.3. Packing Materials & Accessories Parts List |
35 |
|
10.1. Power Circuit |
18 |
|
14.4. Packaging |
35 |
|
10.2. Transformer Circuit and AC Inlet Circuit |
20 |
|
|
|
2
SB-WA930EE
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 cabinet 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-WA930EE
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 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).
·When 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.
3 Before Repair and Adjustment
Disconnect AC power, discharge Power Supply Capacitors C546~C549, C601~C604 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 consumption at AC230 V, 50 Hz in NO SIGNAL mode should be ~1000 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.
4
SB-WA930EE
5Connection of the Speaker Cables
·Be sure to connect speaker cables before connecting the AC power supply cord.
·The load impedance of any speaker used with this unit must be 4Ω.
·Be sure to connect the cable from the right speaker 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-WA930EE
6 Disassembly Procedure
“ATTENTION SERVICER”
Some chassis components may have sharp edges. Be careful when disassembling and servicing.
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 Woofer Speaker Unit 1
·Disassembly of Woofer Speaker Unit 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. and Amplifier P.C.B.
·Disassembly and checking of the Power P.C.B. and Transformer P.C.B.
·Replacement of Power ICs and Transistors
6.1.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.
6.1.1.Disassembly of Front Panel Assembly
6
SB-WA930EE
6.1.2.Disassembly of Rear Assembly
7
SB-WA930EE
6.2.Disassembly of the Speaker Unit and Checking of the P.C.B.
6.2.1.Disassembly of the Front Panel Unit
Step 1: Slot in a steel ruler to give a gap between the Front Panel Unit and the Speaker Cabinet Assembly 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 Speaker Cabinet Assembly Unit.
Steps 2: Slot a piece of wood chip in between the Front Panel Unit and the steel ruler as arrow shown.
Step 4: Remove the Front Panel Unit from the Speaker Cabinet Assembly Unit as arrow shown.
8
· Assembly of the Front Panel Unit.
Step 1: Clean up the remaining glue at the 6 bosses points and replace with the normal glue.
Step 2: Replace the Front Panel Unit firmly back to the Speaker Cabinet Assembly Unit.
6.2.2.Disassembly of the Woofer Speaker 1
Follow Step (1) to Step (4) described in section 6.2.1.
SB-WA930EE
Step 1: Remove 4 screws.
Step 2: Remove the Woofer 1 by detaching the (+) red and (-) black wires.
6.2.3.Disassembly of the Woofer Speaker 2
Follow Step (1) to Step (4) described in section 6.2.1.
9
SB-WA930EE
6.2.4. Disassembly of the Power Amp
Unit
Step 1: Remove 4 screws.
Step 1: Lay the speaker unit as shown. Remove 7 screws from the bottom of the Speaker Cabinet Assembly Unit.
Step 2: Remove the Woofer 2 by detaching the (+) red and (-) black wires.
Step 2: Remove 3 screws from the rear panel.
10
Step 3: Pull out the Power Amp Unit slightly as arrow shown.
Step 4: Disconnect the connector (CN604).
Step 5: Pull out the entire Power Amp Unit.
SB-WA930EE
6.2.5.Disassembly of the Rear Panel and Fan Unit
Follow Step (1) to Step (5) described in section 6.2.4.
Steps 1 & 2: Remove 6 screws from the rear panel.
Step 3: Disconnect the connector (CN507) to detach the rear panel.
Step 4: Remove 4 screws from the rear panel.
11
Loading...