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WARNING: BEFORE SERVICING THIS CHASSIS, READ THE "SAFETY PRECAUTION" AND "PRODUCT SAFETY
NOTICE" INSTRUCTIONS BELOW.
SAFETY PRECAUTION
WARNING: SERVICE SHOULD NOT BE ATTEMPTED BY ANYONE UNFAMILIAR WITH THE NECESSARY PRECAU-
TIONS 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.
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.
3.
Always advise users to keep children away. There is danger of injury to children from tools, disassembled
products, etc.
4.
Always disconnect the power plug before starting work whenever power is not required. Failure to disconnect
the power plug before starting work can result in electrical shock.
5.
Depending on the model, use an insulation transformer or wear 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 have the necessary 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
mark is included in a circuit diagram or parts list.
7.
Parts mounting and routing of the wiring should be the same as that used originally. For safety purposes,
insulating materials such as tubing or tape is sometimes used and printed circuit boards are sometimes mounted
floating. Also make sure that wiring is routed and clamped to avoid parts that generate heat and which use high
voltage. Always follow the original scheme.
8.
After a repair has been completed, reassemble all disassembled parts, and route and reconnect the wiring, in
accordance with the original scheme. 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, as shown in Figure D.1.
• The potential at any point (TOUCH CURRENT) expressed as voltage U1 and U2 does not exceed the follow-
ing value:
The part or contact of a TERMINAL is not HAZARDOUS LIVE if:
a) the open-circuit voltage does not exceed 35 V (peak) a.c. or 60 V d.c., or, if a) is not met,
b) the measurement of the TOUCH-CURRENT shall be carried out in accordance with IEC 60990, with the
measuring network described in annex D of this standard.
The TOUCH CURRENT expressed as voltages U
− − − − − for a.c.: U
= 35 V (peak) and U
1
− − − − − for d.c.: U
= 1,0 V,
1
NOTE - The limit values of U
mA d.c.
The limit value U
= 35 V (peak) for corresponds to the value 70 mA (peak) a.c. for frequencies greater than 100 kHz.
1
SAFETY INSTRUCTIONS
= 0,35 V (peak);
2
= 0,35 V (peak) for a.c. and U
2
and U
, does not exceed the following values:
1
2
=1,0 V for d.c. correspond to the values 0,7 mA (peak) a.c. and 2,0
1
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