Protection Circuitry; Safety Part Information; Prevention Of Electro Static Discharge (Esd) To Electrostatically Sensitive (Es) Devices - Panasonic SA-AK350E Service Manual

SA-AK350E / SA-AK350EB / SA-AK350EG
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 220-240V, 50 Hz in NO SIGNAL mode (volume min at CD mode) should be ~ 350mA.
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
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
2 Prevention of Electro Static Discharge (ESD) to
Electrostatically Sensitive (ES) Devices
Some semiconductor (solid state) devices can be damaged easily by electricity. Such components commonly are called
Electrostatically Sensitive (ES) Devices. Examples of typical ES devices are integrated circuits and some field-effect transistors and
semiconductor "chip" components. The following techniques should be used to help reduce the incidence of component damage
caused by electro static discharge (ESD).
1. Immediately before handling any semiconductor component or semiconductor-equiped assembly, drain off any ESD on your
body by touching a known earth ground. Alternatively, obtain and wear a commercially available discharging ESD wrist strap,
which should be removed for potential shock reasons prior to applying power to the unit under test.
2. After removing an electrical assembly equiped with ES devices, place the assembly on a conductive surface such as aluminium
foil, to prevent electrostatic charge build up or exposure of the assembly.
in the Schematic Diagrams & Replacement Parts List. It is essential that these critical parts should
Reference No.
L5601 G0B9R5K00001
L5602 G0B9R5K00001
L5603 G0B9R5K00001
L5604 G0B9R5K00001
L5950 ELF15N035AN
T5950 G4CYAYY00136
T5951 G4C2AAJ00005
Z5950 ERZV10V511CS
RL5950 K6B1AEA00015
F1 K5D202BLA013
FP5920 K5G702A00009
FP5940 K5G702Z00004
FP5950 K5G402A00025
JK5950 K2AA2B000011
A2 K2CQ2CA00006
A2 K2CT3CA00004
C5920 ECA1HM102E
360 RAE0165A-V
Part No. Part name & Description
CHOKE COIL
CHOKE COIL
CHOKE COIL
CHOKE COIL
LINE FILTER
MAIN TRANSFORMER
SUB TRANSFORMER
POWER RELAY
FUSE PROTECTOR
FUSE PROTECTOR
FUSE PROTECTOR
JK AC INLET
AC CORD
AC CORD
1000 50V
TRAVERSE UNIT
6
Remarks
ZENER
FUSE
EG/ E
EB