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5

Disconnect AC power, discharge unit AC Capacitors as such C4300, C4701, C5117, C5121, C5128, C5133, C5134, C5712,
C5805, C5813 through a 10

Ω, 1W 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 230 V, at 50 Hz in DVD mode (at volume min) should be 200~800 mA.

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.

6

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.

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Some semiconductor (solid state) devices can be damaged easily by electricity. Such components commonly are called Electrostat-
ically Sensitive (ES) Devices. Examples of typical ES devices are integrated circuits and some field-effect transistors and semicon-
ductor “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 alumin-

ium foil, to prevent electrostatic charge build up or exposure of the assembly.

3. Use only a grounded-tip soldering iron to solder or unsolder ES devices.
4. Use only an anti-static solder remover device. Some solder removal devices not classified as “anti-static (ESD protected)” can

generate electrical charge to damage ES devices.

5. Do not use freon-propelled chemicals. These can generate electrical charges sufficient to damage ES devices.
6. Do not remove a replacement ES device from its protective package until immediately before you are ready to install it. (Most

replacement ES devices are packaged with leads electrically shorted together by conductive foam, aluminium foil or compara-
ble conductive material).

7. Immediately before removing the protective material from the leads of a replacement ES device, touch the protective material

to the chassis or circuit assembly into which the device will be installed.
Caution

Be sure no power is applied to the chassis or circuit, and observe all other safety precautions.

8. Minimize body motions when handling unpackaged replacement ES devices. (Otherwise harmless motion such as the brush-

ing together of your clothes fabric or the lifting of your foot from a carpeted floor can generate static electricity (ESD) sufficient

to damage an ES device).

8

The lead free solder has been used in the mounting process of all electrical components on the printed circuit boards used for this
equipment in considering the globally environmental conservation.

The normal solder is the alloy of tin (Sn) and lead (Pb). On the other hand, the lead free solder is the alloy mainly consists of tin
(Sn), silver (Ag) and Copper (Cu), and the melting point of the lead free solder is higher approx.30 degrees C (86

°F) more than that

of the normal solder.

• The lead free solder has to be used when repairing the equipment for which the lead free solder is used.

(Definition: The letter of “PbF” is printed on the PCB using the lead free solder.)

• To put lead free solder, it should be well molten and mixed with the original lead free solder.
• Remove the remaining lead free solder on the PCB cleanly for soldering of the new IC.
• Since the melting point of the lead free solder is higher than that of the normal lead solder, it takes the longer time to melt the

lead free solder.

• Use the soldering iron (more than 70W) equipped with the temperature control after setting the temperature at 350±30 degrees

C (662±86

°F).

• The following 3 types of lead free solder are available through the service parts route.

RFKZ03D01K-----------(0.3mm 100g Reel)
RFKZ06D01K-----------(0.6mm 100g Reel)
RFKZ10D01K-----------(1.0mm 100g Reel)

* Ingredient: Tin (Sn), 96.5%, Silver (Ag) 3.0%, Copper (Cu) 0.5%, Cobalt (Co) / Germanium (Ge) 0.1 to 0.3%

The letter of “PbF” is printed either foil side or components side on the PCB using the lead free solder.
(See right figure)