Lesson18SignalgeneratorKeywords■configure配置

■parameter參數■modulate調制

■carrier載波■instantanous瞬間的

■amplitude幅度■transmission傳輸

■channel調制■工作任務：如何產生高頻連續信號，調制信號和掃描輸出？■學習目標：掌握射頻信號發生器的功能和基本操作■重點難點：射頻信號發生器的基本操作■推薦學時：6學時工作任務：任務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