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  <element name="ScheduleOfShareBasedCompensationArrangementByShareBasedPaymentAwardTotalSharesAvailableTableTextBlock" id="ter_ScheduleOfShareBasedCompensationArrangementByShareBasedPaymentAwardTotalSharesAvailableTableTextBlock" type="nonnum:textBlockItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="ScheduleOfShareBasedPaymentAwardTotalShareholderReturnPlanValuationAssumptionsTableTextBlock" id="ter_ScheduleOfShareBasedPaymentAwardTotalShareholderReturnPlanValuationAssumptionsTableTextBlock" type="nonnum:textBlockItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
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  <element name="ScheduleOfWeightedAverageStockOptionsExercisePriceTableTextBlock" id="ter_ScheduleOfWeightedAverageStockOptionsExercisePriceTableTextBlock" type="nonnum:textBlockItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
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  <element name="SemiconductorTestAndSystemTestGroupMember" id="ter_SemiconductorTestAndSystemTestGroupMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="SemiconductorTestAndWirelessTestMember" id="ter_SemiconductorTestAndWirelessTestMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="SemiconductorTestMember" id="ter_SemiconductorTestMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsAdditionalSharesReservedInPeriod" id="ter_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsAdditionalSharesReservedInPeriod" type="xbrli:sharesItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
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  <element name="ShareBasedCompensationArrangementByShareBasedPaymentAwardVestingPercentageUponOneYearAnniversaryOfDateOfGrant" id="ter_ShareBasedCompensationArrangementByShareBasedPaymentAwardVestingPercentageUponOneYearAnniversaryOfDateOfGrant" type="num:percentItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
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  <element name="ShareholderReturnPerformanceBasedRestrictedStockUnitsMember" id="ter_ShareholderReturnPerformanceBasedRestrictedStockUnitsMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="SharesOfStockIssuedDuringPeriodShareBasedCompensationNetOfSharesWithheldForTaxes" id="ter_SharesOfStockIssuedDuringPeriodShareBasedCompensationNetOfSharesWithheldForTaxes" type="xbrli:sharesItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
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  <element name="StockIssuedDuringPeriodSharesSaleOfStockAndExerciseOfStockOptions" id="ter_StockIssuedDuringPeriodSharesSaleOfStockAndExerciseOfStockOptions" type="xbrli:sharesItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="StockIssuedDuringPeriodValueShareBasedCompensationNetOfSharesWithheldForTaxes" id="ter_StockIssuedDuringPeriodValueShareBasedCompensationNetOfSharesWithheldForTaxes" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="duration" xbrli:balance="credit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="StockRepurchaseProgramsLineItems" id="ter_StockRepurchaseProgramsLineItems" type="xbrli:stringItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
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  <element name="StockRepurchaseProgramTextBlock" id="ter_StockRepurchaseProgramTextBlock" type="nonnum:textBlockItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
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  <element name="SystemsTestGroupMember" id="ter_SystemsTestGroupMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="TaiwanPlanMember" id="ter_TaiwanPlanMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="TaxCreditCarryforwardExpirationYear" id="ter_TaxCreditCarryforwardExpirationYear" type="xbrli:gYearItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="TestSystemsLeasedByCustomersMember" id="ter_TestSystemsLeasedByCustomersMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="TestSystemsManufacturedInternallyMember" id="ter_TestSystemsManufacturedInternallyMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
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  <element name="UnitedKingdomDefinedBenefitPensionPlanMember" id="ter_UnitedKingdomDefinedBenefitPensionPlanMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="UnitedKingdomGovernmentSecuritiesMember" id="ter_UnitedKingdomGovernmentSecuritiesMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="UnitedStatesEquityLargeCapMember" id="ter_UnitedStatesEquityLargeCapMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="UnitedStatesPlansMember" id="ter_UnitedStatesPlansMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="UnitedStatesSupplementalExecutiveDefinedBenefitPensionPlanMember" id="ter_UnitedStatesSupplementalExecutiveDefinedBenefitPensionPlanMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
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  <element name="UnrecognizedTaxBenefitsIfRecognizedWouldImpactValuationAllowance" id="ter_UnrecognizedTaxBenefitsIfRecognizedWouldImpactValuationAllowance" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="instant" xbrli:balance="credit" nillable="true" substitutionGroup="xbrli:item"/>
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  <element name="UsGovernmentFixedIncomeMember" id="ter_UsGovernmentFixedIncomeMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="USQualifiedPensionPlanMember" id="ter_USQualifiedPensionPlanMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="WarrantyPeriod" id="ter_WarrantyPeriod" type="xbrli:durationItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="WirelessTestMember" id="ter_WirelessTestMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="ZtecCorporationAndAvionicsInterfaceTechnologiesLlcMember" id="ter_ZtecCorporationAndAvionicsInterfaceTechnologiesLlcMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="ZtecCorporationMember" id="ter_ZtecCorporationMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
</schema>
