
6
SAFETYPRECAUTIONS
Thefollowingitemsshouldbecheckedforcontinuedprotectionofthecustomerandtheservicetechnician.
LEAKAGE CURRENT CHECK
Beforereturningthesettothecustomer,besuretocarryouteither(1)aleakagecurrentcheckor(2)alinetochassis
resistancecheck.Iftheleakagecurrentexceeds0.5milliamps,oriftheresistancefromchassistoeithersideofthe
powercordislessthan460kohms,thesetisdefective.
BesuretotestforleakagecurrentwiththeACpluginbothpolarities,inaddition,whentheset'spowerisineachstate(on,
offandstandbymode),ifapplicable.
CAUTION Pleaseheedthefollowingcautionsandinstructionsduringservicingand
inspection.
◎Heed the cautions!
Cautionswhicharedelicateinparticularforservicing
arelabeledonthecabinets,thepartsandthechassis,
etc. Be sure to heed these cautions and the cautions
described in the handling instructions.
◎Cautions concerning electric shock!
(1) AnACvoltageisimpressedonthisset,soif
youtouchinternalmetalpartswhenthesetis
energized,youmaygetanelectricshock.Avoid
gettinganelectricshock,byusinganisolating
transformer and wearing gloves when servicing
whilethesetisenergized,orbyunpluggingthe
powercordwhenreplacingparts,forexample.
(2) Therearehighvoltagepartsinside.Handlewith
extra care whenthesetisenergized.
◎Caution concerning disassembly and
assembly!
Throughgreatcareistakenwhenpartswere
manufacturedfromsheetmetal,theremaybeburrs
ontheedgesofparts.Theburrscouldcauseinjuryif
ngersaremovedacrosstheminsomerarecases.
Wearglovestoprotectyourhands.
◎Use only designated parts!
Theset'spartshavespecicsafetyproperties(re
resistance,voltageresistance,etc.).Besuretouse
partswhichhavethesamepropertiesforreplacement.
Theburrshavethesameproperties.Inparticular,for
theimportantsafetypartsthatareindicatedbythez
markonschematicdiagramsandpartslists,besureto
use the designatedparts.
◎Be sure to mount parts and arrange the wires
as they were originally placed!
Forsafetyseasons,somepartsusetapes,tubesor
otherinsulatingmaterials,andsomepartsaremounted
awayfromthesurfaceofprintedcircuitboards.
Careisalsotakenwiththepositionsofthewiresby
arrangingthemandusingclampstokeepthemaway
fromheatingandhighvoltageparts,sobesuretoset
everythingbackasitwasoriginallyplaced.
◎Make a safety check after servicing!
Checkthatallscrews,partsandwiresremovedor
disconnectedwhenservicinghavebeenputbackin
theiroriginalpositions,checkthatnoservicedparts
havedeterioratetheareaaround.Thenmakean
insulation check on the external metal connectors and
betweenthebladesofthepowerplug,andotherwise
checkthatsafetyisensured.
(Insulationcheckprocedure)
Unplugthepowercordfromthepoweroutlet,
disconnecttheantenna,plugs,etc.,andonthepower.
Using a 500V insulation resistance tester, check that
theinsulationresistancevaluebetweentheinplugand
theexternallyexposedmetalparts(antennaterminal,
headphonesterminal,inputterminal,etc.)is1MΩor
greater.Ifitisless,thesetmustbeinspectedand
repaired.
Manyoftheelectricandthestructuralpartsusedin
thesethavespecialsafetyproperties.Inmostcases
thesepropertiesaredifculttodistinguishbysight,and
theuseofreplacementpartswithhigherratings(rated
powerandwithstandvoltage)doesnotnecessarily
guaranteethatsafetyperformancewillbepreserved.
Partswithsafetypropertiesareindicatedasshown
belowonthewiringdiagramsandthepartslistinthis
servicemanual.Besuretoreplacethemwiththeparts
whichhavethedesignatedpartnumber.
(1) Schematicdiagrams.......Indicatedbythez mark.
(2) Partslists.......Indicatedbythezmark.
Theuseofpartsotherthanthe
designatedpartscouldcauseelectric
shocks,resorotherdangerous
situations.
CAUTION Concerning important safety
parts