JVC HR-S9850EK, Service Manual

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Important Safety Precautions
Prior to shipment from the factory, JVC products are strictly inspected to conform with the recognized product safety and electrical codes
of the countries in which they are to be sold. However, in order to maintain such compliance, it is equally important to implement the
following precautions when a set is being serviced.
Fig.1
1. Locations requiring special caution are denoted by labels and
inscriptions on the cabinet, chassis and certain parts of the
product. When performing service, be sure to read and com-
ply with these and other cautionary notices appearing in the
operation and service manuals.
2. Parts identified by the symbol and shaded ( ) parts are
critical for safety.
Replace only with specified part numbers.
Note: Parts in this category also include those specified to com-
ply with X-ray emission standards for products using
cathode ray tubes and those specified for compliance
with various regulations regarding spurious radiation
emission.
3. Fuse replacement caution notice.
Caution for continued protection against fire hazard.
Replace only with same type and rated fuse(s) as specified.
4. Use specified internal wiring. Note especially:
1) Wires covered with PVC tubing
2) Double insulated wires
3) High voltage leads
5. Use specified insulating materials for hazardous live parts.
Note especially:
1) Insulation Tape
3) Spacers 5) Barrier
2) PVC tubing 4) Insulation sheets for transistors
6. When replacing AC primary side components (transformers,
power cords, noise blocking capacitors, etc.) wrap ends of
wires securely about the terminals before soldering.
Power cord
Fig.2
10. Also check areas surrounding repaired locations.
11. Products using cathode ray tubes (CRTs)
In regard to such products, the cathode ray tubes themselves,
the high voltage circuits, and related circuits are specified for
compliance with recognized codes pertaining to X-ray emission.
Consequently, when servicing these products, replace the cath-
ode ray tubes and other parts with only the specified parts.
Under no circumstances attempt to modify these circuits.
Unauthorized modification can increase the high voltage value
and cause X-ray emission from the cathode ray tube.
12. Crimp type wire connector
In such cases as when replacing the power transformer in sets
where the connections between the power cord and power
transformer primary lead wires are performed using crimp type
connectors, if replacing the connectors is unavoidable, in or-
der to prevent safety hazards, perform carefully and precisely
according to the following steps.
1) Connector part number : E03830-001
2) Required tool : Connector crimping tool of the proper type
which will not damage insulated parts.
3) Replacement procedure
(1) Remove the old connector by cutting the wires at a point
close to the connector.
Important : Do not reuse a connector (discard it).
Fig.7
cut close to connector
Fig.3
(2) Strip about 15 mm of the insulation from the ends of
the wires. If the wires are stranded, twist the strands to
avoid frayed conductors.
15 mm
Fig.4
(3) Align the lengths of the wires to be connected. Insert
the wires fully into the connector.
Connector
Metal sleeve
Fig.5
(4) As shown in Fig.6, use the crimping tool to crimp the
metal sleeve at the center position. Be sure to crimp fully
to the complete closure of the tool.
1
v
Precautions during Servicing
7. Observe that wires do not contact heat producing parts
(heatsinks, oxide metal film resistors, fusible resistors, etc.)
8. Check that replaced wires do not contact sharp edged or
pointed parts.
9. When a power cord has been replaced, check that 10-15 kg of
force in any direction will not loosen it.
1.25
2.0
5.5
Crimping tool
Fig.6
(5) Check the four points noted in Fig.7.
Not easily pulled free
Crimped at approx. center
of metal sleeve
Conductors extended
Wire insulation recessed
more than 4 mm
S40888-01