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TIATELECOMMUNICATIONSSYSTEMSBULLETINApplicationGuidelinesforTIA/EIA-485-ATSB-89-A(RevisionofTSB-89)January2006TELECOMMUNICATIONSINDUSTRYASSOCIATIONTheTelecommunicationsIndustryAssociationrepresentsthecommunicationssectorofNOTICETIAEngineeringStandardsandPublicationsaredesignedtoservethepublicinterestthrougheliminatingmisunderstandingsbetweenmanufacturersandpurchasers,facilitatinginterchangeabilityandimprovementofproducts,andassistingthepurchaserinselectingandobtainingwithminimumdelaytheproperproductfortheirparticularneed.TheexistenceofsuchStandardsandPublicationsshallnotinanyrespectprecludeanymemberornon-memberofTIAfrommanufacturingorsellingproductsnotconformingtosuchStandardsandPublications.NeithershalltheexistenceofsuchStandardsandPublicationsprecludetheirvoluntaryusebyNon-TIAmembers,eitherdomesticallyorinternationally.StandardsandPublicationsareadoptedbyTIAinaccordancewiththeAmericanNationalStandardsInstitute(ANSI)patentpolicy.Bysuchaction,TIAdoesnotassumeanyliabilitytoanypatentowner,nordoesitassumeanyobligationwhatevertopartiesadoptingtheStandardorPublication.ThisStandarddoesnotpurporttoaddressallsafetyproblemsassociatedwithitsuseorallapplicableregulatoryrequirements.ItistheresponsibilityoftheuserofthisStandardtoestablishappropriatesafetyandhealthpracticesandtodeterminetheapplicabilityofregulatorylimitationsbeforeitsuse.(FromStandardsProposalNo.3-3615-RV1,formulatedunderthecognizanceoftheTIATR-30.2SubcommitteeonDTE-DCEInterfaces).Publishedby©TELECOMMUNICATIONSINDUSTRYASSOCIATIONStandardsandTechnologyDepartment2500WilsonBoulevardArlington,VA22201U.S.A.PRICE:PleaserefertocurrentCatalogofTIATELECOMMUNICATIONSINDUSTRYASSOCIATIONSTANDARDSANDENGINEERINGPUBLICATIONSorcallGlobalEngineeringDocuments,USAandCanada(1-800-854-7179)International(303-397-7956)orsearchonlineat(includingpostingontheweb)isprohibitedwithoutcopyrightpermission.Forcopyrightpermissiontoreproduceportionsofthisdocument,pleasecontactTIAStandardsDepartmentorgototheTIAwebsite()fordetailsonhowtorequestpermission.Detailsarelocatedat:=18ORTelecommunicationsIndustryAssociationStandards&TechnologyDepartment2500WilsonBoulevard,Suite300Arlington,VA22201USA+1(703)907-7700Organizationsmayobtainpermissiontoreproducealimitednumberofcopiesbyenteringintoalicenseagreement.Forinformation,contact:GlobalEngineeringDocuments15InvernessWayEastEnglewood,CO80112-5704orcallU.S.A.andCanada(1-800-854-7179)International(303)397-7956NOTICEOFDISCLAIMERANDLIMITATIONOFLIABILITYThedocumenttowhichthisNoticeisaffixed(the“Document”)hasbeenpreparedbyoneormoreEngineeringCommitteesorFormulatingGroupsoftheTelecommunicationsIndustryAssociation(“TIA”).TIAisnottheauthoroftheDocumentcontents,butpublishesandclaimscopyrighttotheDocumentpursuanttolicensesandpermissiongrantedbytheauthorsofthecontents.TIAEngineeringCommitteesandFormulatingGroupsareexpectedtoconducttheiraffairsinaccordancewiththeTIAEngineeringManual(“Manual”),thecurrentandpredecessorversionsofwhichareavailableat’sfunctionistoadministertheprocess,butnotthecontent,ofdocumentpreparationinaccordancewiththeManualand,whenappropriate,thepoliciesandproceduresoftheAmericanNationalStandardsInstitute(“ANSI”).TIAdoesnotevaluate,test,verifyorinvestigatetheinformation,accuracy,soundness,orcredibilityofthecontentsoftheDocument.InpublishingtheDocument,TIAdisclaimsanyundertakingtoperformanydutyowedtoorforanyone.IftheDocumentisidentifiedormarkedasaprojectnumber(PN)document,orasastandardsproposal(SP)document,personsorpartiesreadingorinanywayinterestedintheDocumentarecautionedthat:(a)theDocumentisaproposal;(b)thereisnoassurancethattheDocumentwillbeapprovedbyanyCommitteeofTIAoranyotherbodyinitspresentoranyotherform;(c)theDocumentmaybeamended,modifiedorchangedinthestandardsdevelopmentoranyeditingprocess.TheuseorpracticeofcontentsofthisDocumentmayinvolvetheuseofintellectualpropertyrights(“IPR”),includingpendingorissuedpatents,orcopyrights,ownedbyoneormoreparties.TIAmakesnosearchorinvestigationforIPR.WhenIPRconsistingofpatentsandpublishedpendingpatentapplicationsareclaimedandcalledtoTIA’sattention,astatementfromtheholderthereofisrequested,allinaccordancewiththeManual.TIAtakesnopositionwithreferenceto,anddisclaimsanyobligationtoinvestigateorinquireinto,thescopeorvalidityofanyclaimsofIPR.TIAwillneitherbeapartytodiscussionsofanylicensingtermsorconditions,whichareinsteadlefttothepartiesinvolved,norwillTIAopineorjudgewhetherproposedlicensingtermsorconditionsarereasonableornon-discriminatory.TIAdoesnotwarrantorrepresentthatproceduresorpracticessuggestedorprovidedintheManualhavebeencompliedwithasrespectstheDocumentoritscontents.TIAdoesnotenforceormonitorcompliancewiththecontentsoftheDocument.TIAdoesnotcertify,inspect,testorotherwiseinvestigate