Panasonic SU-HTB880EB, Service Manual

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1.3. Before Repair and Adjustment
1.3.1. Main Unit (SU-HTB880)
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 120 V, 60 Hz during power on at no signal with volume minimum, should be ~150 mA (For PP only).
• Current consumption at AC 220 V ~ 240 V, 50 Hz during power on at no signal with volume minimum, should be ~200 mA (For
EB/EG/GN only).
1.3.2. Active Subwoofer (SB-HWA880)
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 120 V, 60 Hz during power on at link with volume minimum, (Selector : BD/DVD mode) should be
~200 mA (For PP only).
• 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 (For EB/EG/GN only).
1.4. 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.
• 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.
1.5. Caution For Fuse Replacement