Panasonic SU-HTB685GN, Service Manual

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1 Safety Precautions
1.1. Before Repair and Adjustment
1.1.1. Main Speaker Unit (SU-HTB685)
Disconnect AC power, discharge unit AC Capacitors (C5700, C5701, C5702, C5703, C5704 and C5705) through a 10W, 1W resis-
tor to ground.
Caution : 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 AC 220 V ~ 240 V, 50 Hz during power on at no signal with volume minimum, should be ~150 mA.
1.1.2. Active Subwoofer (SB-HWA685)
Disconnect AC power, discharge unit AC Capacitors (C5700, C5701, C5702, C5703, C5704 and C5705) through a 10W, 1W resis-
tor to ground.
Caution : 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 AC 220 V ~ 240 V, 50 Hz during power on at link with volume minimum, (Selector : BD/DVD mode)
should be ~200 mA.
1.2. 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.
• Sound 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.
1.3. Caution For Fuse Replacement
1.4. Safety Part Information
Safety Parts List:
There are special components used in this equipment which are important for safety.
These parts are marked by in the Schematic Diagrams & Replacement Parts List. It is essential that these critical parts should
be replaced with manufacturer’s specified parts to prevent shock, fire or other hazards. Do not modify the original design without
permission of manufacturer.
1.4.1. Main Speaker Unit (SU-HTB685)
Safety Ref. No. Part No. Part Name & Description Remarks
15 RGN3656-K NAME PLATE
PCB5 REP5047KA SMPS P.C.B. (RTL)
DZ5701 ERZV10V511CS ZNR (E.S.D)
L5702 G0B922G00004 LINE FILTER
L5703 G0B203G00005 LINE FILTER
T5701 G4DYA0000573 TRANSFORMER
PC5720 B3PBA0000579 PHOTO COUPLER
PC5760 B3PBA0000579 PHOTO COUPLER
F1 K5G312Y00007 FUSE
P5701 K2AA2B000011 AC INLET