Lesson18SignalgeneratorKeywords■configure配置

■parameter參數(shù)■modulate調(diào)制

■carrier載波■instantanous瞬間的

■amplitude幅度■transmission傳輸

■channel調(diào)制■工作任務(wù)：如何產(chǎn)生高頻連續(xù)信號(hào)，調(diào)制信號(hào)和掃描輸出？■學(xué)習(xí)目標(biāo)：掌握射頻信號(hào)發(fā)生器的功能和基本操作■重點(diǎn)難點(diǎn)：射頻信號(hào)發(fā)生器的基本操作■推薦學(xué)時(shí)：6學(xué)時(shí)工作任務(wù)：任務(wù)1：Configureawaveof700MHzand-20dbmwithN5181A/82AMXGGenerate

PresetthesignalgeneratorToreturnthesignalgeneratortoaknownstate,presseitherPresetorUserPreset.Presetisthefactorypreset;UserPresetisacustompreset.Toresetpersistentsettings(thoseunaffectedbypreset,userpreset,orpowercycle),Press:Utility>PowerOn/Preset>RestoreSystemDefaults.Wealsoshouldcaution：Toavoidthelossofdata,GPIBsettings,orcurrentuserinstrumentstatesthathavenotbeenpermanentlysavedtonon-volatilememory,theMXGshouldalwaysbepowereddowneitherviatheMXG'sfrontpanelpowerbuttonortheappropriateSCPIcommand.MXG'sinstalledinracksystemsandpowereddownwiththesystemrackpowerswitchratherthantheMXG'sfrontpanelswitchdisplayaError-310duetotheMXGnotbeingpowereddowncorrectly.Makethesignalgeneratordisplaythedesignatedfrequencyandminimumpowerlevel.SetRFfrequencyPressFreq>700>MHzstepbystep.InFrequencymode,thismenuisautomaticallydisplayedwhenenteringanumericvaluewiththefrontpanelkeypad.SettheRFamplitudePressAmptd>-20>dBmstepbystep.InAmplitudemode,thismenuisautomaticallydisplayedwhenenteringanumericvaluewiththefrontpanelkeypad.DBuVemfterminatesthevalueasdBuVelectromotiveforce.Emfistheoutputvoltagewithnoload.Thisunitisexternalonly.InternalrepresentationaswellasincrementanddecrementvaluesareindBm.Note:dBuV,mV,andnVemfbehavesimilarly(i.e.Valuesareexternalonly.InternalrepresentationaswellasincrementanddecrementvaluesareindBm.).TurnontheRFOutputPressRFOn/Off，

theRFoutputLEDlights,indicatingthatthesignalistransmittingfromtheRFoutputconnector.Here

任務(wù)2：GenerateanAMsignalGeneratePresetthesignalgeneratorSetthecarrierfrequencySettheRFamplitudeConfigurethemodulation1.PressAMSettheAMtype(LinearorExponential):AMTypetohighlightdesiredtype.SettheAMMode(NormalorDeep).DefaultisDeep.ToselectNormalenableMoretohighlightdesiredtype.SettheAMDepth:AMDepth>value（Default0.01%andrange0.01to100%）Settherate:AMRate>value>frequencyunitTurnonthemodulationPressAM>AMOffOn.TurnontheRFoutputTheRFoutputLEDlights,indicatingthatthesignalistransmittingfromtheRFoutputconnector.任務(wù)3：ConfiguringaSweptOutputThesignalgeneratorispowerful.Itcannotonlygeneratecontinuouswavesandmodulatedsignals，butalsoachievesweepingoutput.1.Setupeitherastepsweep(page52)oralistsweep(page58).2.IntheSweep/Listmenu,selectaparametertosweep:PressSweep>parameter>Return.3.Selectmanualmode:PressMore>ManualModeOffOn.Whenyouselectmanualmode,thecurrentsweeppointbecomestheselectedmanualpoint.4.Ifitisnotalreadyon,turntheRFoutputon:PressRFOn/Off.5.Selectthedesiredpointtooutput:PressManualPoint>number>Enter.Theprogressbarchangestoindicatetheselectedpoint.6.Usetheknoborarrowkeystomovefrompointtopoint.Asyouselecteachpoint,theRFoutputchangestothesettin