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SAFETY INSTRUCTION
WARNING:
BEFORE SERVICING THIS CHASSIS, READ THE "SAFETY PRECAUTION" AND "PRODUCT SAFETY NOTICE"
INSTRUCTIONS BELOW.
Safety Precaution
WARNING:
SERVICING SHOULD NOT BE ATTEMPTED BY ANYONE UNFAMILIAR WITH THE NECESSARY PRECAUTIONS ON THIS
RECEIVER. THE FOLLOWING ARE THE NECESSARY PRECAUTIONS TO BE OBSERVED BEFORE SERVICING THIS CHASSIS.
1. An isolation transformer should be connected in the power line between the receiver and the AC line before any service is performed on the
receiver.
2. Always disconnect the power plug before any disassembling of the product. It may result in electrical shock.
3. When replacing a chassis in the cabinet, always be certain that all the protective devices are put back in place, such as nonmetallic control
knobs, insulating covers, shields, isolation resistor-capacitor network, etc.
4. Always keep tools, components of the product, etc away from the children, These items may cause injury to children.
5. Depending on the model, use an isolation transformer or wear suitable gloves when servicing with the power on, and disconnect the power
plug to avoid electrical shock when replacing parts. In some cases, alternating current is also impressed in the chassis, so electrical shock is
possible if the chassis is contacted with the power on.
6. Always use the replacement parts specified for the particular model when making repairs. The parts used in products require special safety
characteristics such as inflammability, voltage resistance, etc. therefore, use only replacement parts that have these same characteristics.
Use only the specified parts when the
7. Parts mounting and routing dressing of wirings should be the same as that used originally. For safety purposes, insulating materials such as
isolation tube or tape are sometimes used and printed circuit boards are sometimes mounted floating. Also make sure that wirings is routed
and clamped to avoid parts that generate heat and which use high voltage. Always follow the manufactured wiring routes / dressings.
8. Always ensure that all internal wirings are in accordance before re-assembling the external casing after a repairing completed. Do not allow
internal wiring to be pinched by cabinets, panels, etc. Any error in reassembly or wiring can result in electrical leakage, flame, etc., and may
be hazardous.
9. NEVER remodel the product in any way. Remodeling can result in improper operation, malfunction, or electrical leakage and flame, which
may be hazardous.
10. Touch current check. (After completing the work, measure touch current to prevent an electric shock.)
Plug the AC cord directly into the AC outlet. Do NOT use an isolation transformer for this check.
Connect a measuring network for touch currents between each exposed metallic part on the set and a good earth ground such as a
water pipe.
Resistance values in orms ( ).
V: Voltmeter or oscilloscope
(r.m.s. or peak reading)
Input resistance :
Input capacitance :
Frequency range : 15 Hz to 1 MHz and d.c. respectively
mark is indicated in the circuit diagram or parts list.
(normative)
Measuring network for TOUCH CURRENTS
1 M
200 pF
Annex D
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