ALI M5677, Service Manual

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2) Read and comply with all caution and safety related
notes non or inside the cabinet, or on the chassis.
3) Design Alteration Warning-Do not alter of add to the
mechanical or electrical design of this instrument.
Design alterations and additions, including but not
limited to, circuit modifications and the addition of
items such as auxiliary audio output connections,
might alter the safety characteristics of this
instrument and create a hazard to the user. Any
design alterations or additions will make you, the
service, responsible for personal injury or property
damage resulting there from.
4) Observe original lead dress. Take extra care to
assure correct lead dress in the following areas:
(1) near sharp edges, (2) near thermally hot parts
(be sure that leads and components do not touch
thermally hot parts), (3) the AC supply, (4) high
voltage, and (5) antenna wiring. Always inspect in
all areas for pinched, out-of-place, or frayed wiring.
Do not change spacing between a component and
the printed-circuit board, Check the AC power
cord for damage.
5) Components, parts, and/or wiring that appear to
have overheated or that are otherwise damaged
should be replaced with components, parts and/or
wiring that meet original specifications.
Additionally determine the cause of overheating
and/or damage and, if necessary, take corrective
action to remove and potential safety hazard.
6) Product Safety Notice-Some electrical and
mechanical parts have special safety-related
characteristics which are often not evident from
visual inspection, nor can the protection they give
necessarily be obtained by replacing them with
components rated for higher voltage, wattage, etc.
Parts that have special safety characteristics are
identified by shading, an ( ) or a ( ) on
schematics and parts lists. Use of a substitute
replacement that does not have the same safety
characteristics as the recommended replacement
part might created shock, fire and/or other
hazards. Product safety is under review
continuously and new instructions are issued
whenever appropriate.
1-2 Servicing Precautions
CAUTION: Before servicing Instruments covered by
this service manual and its supplements, read and
follow the Safety Precautions section of this manual.
Note: If unforeseen circument create conflict between
the following servicing precautions and any of the
safety precautions, always follow the safety
precautions. Remember; Safety First
1-2-1 General Serving Precautions
(1) a. Always unplug the instrument’s AC power cord
from the AC power source before (1) removing or
reinstalling any component, circuit board, module
or any other instrument assembly. (2)
disconnecting any instrument electrical plug or
other electrical connection. (3) connecting a test
substitute in parallel with an electrolytic capacitor
in the instrument.
b. Do not defeat any plug/socket B+ voltage
interlocks with which instruments covered by this
service manual might be equipped.
c. Do not apply AC power to this instrument and/or
any of its electrical assemblies unless all
solid-state device heat sinks are correctly
installed.
d. Always connect a test instrument’s ground lead
to the instrument chassis ground before
connecting the test instrument positive lead.
Always remove the test instrument ground lead
last.
Note: Refer to the Safety Precautions section
ground lead last.
(2) The service precautions are indicated or printed on
the cabinet, chassis or components. When
servicing, follow the printed or indicated service
precautions and service materials.
(3) The components used in the unit have a specified
flame resistance and dielectric strength.
When replacing components, use components
which have the same ratings, by ( ) or by ( )
in the circuit diagram are important for safety or
for the characteristics of the unit. Always replace
them with the exact replacement components.
(4) An insulation tube or tape is sometimes used and
some components are raised above the printed
wiring board for safety. The internal wiring is
sometimes clamped to prevent contact with
heating components. Install such elements as
they were.
(5) After servicing, always check that the removed
screws, components, and wiring have been
installed correctly and that the portion around the
serviced part has not been damaged and so on.
Further, check the insulation between the blades
of the attachment plus and accessible conductive
parts.
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