Daewoo DS-2000N, Руководство по обслуживанию

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CAUTION : Before servicing the DVD covered by this
service data and its supplements and ADDENDUMS, read
and follow the
: if
unforeseen circumstances create conflict between the
following servicing precautions and any of the safety
precautions in this publications, always follow the safety
precautions.
1. Always unplug the DVD AC power cord from the AC
powersourcebefore:
(1)Removingorreinstallinganycomponent,circuitboard,
module,oranyotherassembly.
(2) Disconnection or reconnecting any internal electrical
plugorotherelectricalconnection.
(3) Connecting a test substi tute in parallel with an
electrolytic capacitor
A wrong part substitution or incorrect
polarity installation of electrolytic capacitors may
resultinanexplosionhazard.
2. Do not spray chemicals on or nearthisDVDoranyofits
assemblies.
3. Unless specified otherwise in this service data, clean
electrical contacts by applying an appropriate contact
cleaning solution to the contacts with a pipe cleaner,
cotton-tipped swab,orcomparablesoftapplicator.
Unless specified otherwise in this service data,
lubricationofcontactsisnotrequired.
4. Do not defeat any plug/socket B+ voltage interlocks with
witch instruments covered by this service manual might
beequipped.
5. Do not apply AC power to this DVD and/or any of its
electrical assemblies unless all solid-state device heat
sinksarecorrectlyinstalled.
6. Always connect test instrument ground lead to the
appropriate ground before connection the test
instrument positive lead. Always remove the test
instrumentgroundleadlast.
Disconnect theattachmentplugtromtheACoutletandturn
thepoweron.Connectaninsulationresistancemeter(500V)
to the blades of the attachment plug. The insulation
resistance between each bladeof the attachment plug and
accessible conductive parts (Note 1) should be more than
1Mohm.
Accessible Conductive Parts including Metal
panels,inputterminals,Earphonejacks,etc.
SAFETY PRECAUTIONS NOTE
RememberSafetyFirst:
General ServicingPrecautions
InsulationChecking Procedure
Caution :
Note 1 :
ElectrostaticallySensitive(ES)Devices
Some semiconductor (solidstate)devicescan bedamaged
easily by static electricity. Such components commonly are
called ElectrostaticallySensitive(ES) Devices.Examplesof
typical ES devices are integrated circuits and some field
effecttransistorsandsemiconductorchipcomponents.
Thefollowingtechniquesshouldbeused tohelpreducethe
incidenceofcomponentdamagecausedbystaticelectricity.
1. Immediately before handling any semiconductor
componentor semiconductor-equippedassembly,drain
off any electrostatic charge on your body by touching a
known earth ground. Alternatively, obtain and wear a
commercially available discharging wrist strap device,
which should be removed for potential shock reasons
priortoapplyingpowertotheunitundertest.
2. Afterremovingan electrical assembly equipped with ES
devices, place the assembly on a conductive surface
such as aluminum toil, to prevent electrostatic charge
builduporexposureoftheassembly.
3. Use only a GROUNDED-tip soldering iron to solder or
unsolderESdevices.
4. Use only an anti-static solder removal device. Some
solder removal devices not classified a "anti-static" can
generate electrical charges sufficient to damage ES
devices.
5. Do not use freon-propelled chemicals. These can
generate electrical charge 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, aluminum foil, or comparable
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
intowhichthedevicewillbeinstalled.
Caution : Be sure no powerisapplied to the chassis or
circuit,andobserveallothersafetyprecautions.
8. Minimize bodily motions when handling unpackaged
replacement ES devices. (Normally harmless motion
suchasthebrushingtogetherofyourclothesfabricorthe
lifting of your foot from a carpeted floor can generate
static electricitysufficienttodamageanESdevice.)
SERVICING PRECAUTIONS