Before Repair And Adjustment; Protection Circuitry; Safety Parts Information - Panasonic SA-AK785LM-K Service Manual

1.4.

Before Repair and Adjustment

Disconnect AC power to discharge unit AC Capacitors as such (C5700, C5701, C5703, C5704, C5705, C5706, C5707) through a
10 ? , 10 W resistor 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 110V~127V / 220V~240V, 50/60 Hz in NO SIGNAL mode volume minimal should be ~ 500 mA (For PH
only).
Current consumption at AC 120V, 60 Hz in NO SIGNAL mode volume minimal should be ~ 500 mA (For PN only).
1.5.

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.
1.6.

Safety Parts Information

Safety Parts List:
There are special components used in this equipment which are important for safety.
These parts are marked by
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.
in the Schematic Diagrams & Replacement Parts List. It is essential that these critical parts
SC-AK785LM-K
Modelo:
Safety Nombre del componente
CABLE TOMACORRIENTE.
CONECTOR TOMACORRIENTE
TRANSFORMADOR DE PODER
TRANSFORMADOR DE
RESPALDO
FUSIBLE PRIMARIO
CAPACITOR DE AC
CAPACITOR DE AC
CAPACITOR DE AC
OPTOACOPLADOR
PCB SMPS
RESISTENCIA FUSIBLE
GAB. MET. SIN DOBLAR
LECTOR ÓPTICO
(CD UNIT)
REAR PANEL
INSTRUCTIVO
BOBINA PRIMARIO
SMPS FX785
Numero de Parte
SJA168-1A
K2AA2B000017
ETS48AB12GAC
ETS19AB256AG
K5D802APA008
F0CAF334A087
F1BAF1020020
F0CAF224A085
B3PBA0000402
RJBX0562T-1
K5G4013A0001
RKMX0144Z-KL
RD-DAC060-PX
RGRX0070R-AL
RQTM0171
ELF22V035B
N0AE6GY00001