Panasonic SA-AK770GCP, Service Manual

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1.3. Before repair and adjustment
Disconnect AC power, discharge AC Capacitors C5700, C5701, C5703, C5704, C5705 (PL Only); C5700, C5701, C5703, C5704,
C5705, C5706 & C5707 (GCP Only) through a 10
Ω
, 5W 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 AC 120V, 60 Hz in NO SIGNAL mode (volume min at CD mode) should be ~ 750mA (For PL only).
Current consumption at AC 110V~127V, 50/60 Hz in NO SIGNAL mode (volume min at CD mode) should be ~ 750mA (For GCP
only).
Current consumption at AC 220V~240V, 50/60 Hz in NO SIGNAL mode (volume min at CD mode) should be ~ 500mA (For GCP
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. 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.
Table 1
Reference No. Part No. Part name & Description Remarks
18 RGRX0070F-A REAR PANEL [M] PL
18 RGRX0070G-A REAR PANEL [M] GCP
36 RKMX0144-K TOP CABINET [M]
51 RMZ0339 ZENER COVER [M] GCP
68 REXX0686 WHITE WIRE (VOLTAGE
SELECTOR)
[M] GCP
69 REXX0687 BLUE WIRE (VOLTAGE
SELECTOR)
[M] GCP
84 REXX0684 BLACK WIRE [M] PL
85 REXX0685 RED WIRE [M] PL
89 REZX0024 RED WIRE [M] GCP
90 REZX0023 BLACK WIRE [M] GCP
340 RAEX0190A-V TRAVERSE ASSEMBLY UNIT [M] (RTL)
A2 K2CB2CB00021 AC CORD [M] PL
A2 K2CQ2CA00007 AC CORD [M] GCP
PCB4 REPX0622E SMPS P.C.B. [M] (RTL) PL
REPX0622G SMPS P.C.B. [M] (RTL) GCP
PCB10 REPX0622E AC INLET P.C.B. [M] (RTL) PL
REPX0622G AC INLET P.C.B. [M] (RTL) GCP
PCB13 REPX0622G VOLTAGE SELECTOR P.C.B. [M] (RTL) GCP
DZ5701 ERZV10V511CS ZENER [M]
S5701 K0ABCA000007 SW VOLTAGE SELECTOR [M] GCP
L5702 ELF22V035B LINE FILTER [M]
T2900 G4D1A0000117 SWITCHING TRANSFORMER [M]
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SA-AK770PL / SA-AK770GCP