12 MEASure Subsystem160 Keysight U2040 X-Series Programming GuideMEASure[1]|2|3|4[:SCALar][:POWer][:AC]:DIFFerence:RELative?SyntaxMEASure[1]|2|3|4[:SCALar][:POWer][:AC]:DIFFerence:RELative?[[,[,]]]DescriptionThis query sets the specified CALCulate block measurement function to the differencemode with relative mode on, aborts, configures then initiates Channel A, calculates thedifference measurement result, and places the result on the bus. The result is a ratio-basedmeasurement and is expressed in the units defined by UNIT[1]|2|3|4:POWer:RATio.The relative value used is that set by the CALCulate:RELative:MAGNitude:AUTOcommand.The values shown in this query are those that are tested.ParametersExampleItem Range of values Description/Default valueexpected_value(for the expected powerlevel)sensor-dependentDEF[a][a] The mnemonic DEF means DEFault. This is not equivalent to the DEFault parameter used in the commandsubsystems. The parameters must be entered in the specified order. If parameters are omitted, they default from theright. The parameter DEFault is used as a placeholder. Specifying DEF leaves the parameter value unchanged.The U2040 X-Series ignores the numeric value entered in thisparameter. Any value entered is treated like DEF.resolution1 to 4[b]1.0, 0.1, 0.01, 0.001DEF[a][b] When SENS:AVER:COUN:AUTO is enabled, the resolution setting affects the number of averages applied. Refer to“Auto-averaging mode” on page 44 for more information.A numeric value for the resolution. If unspecified, the currentresolution setting is used.source_list (@1),(@1)This channel list specifies the channels used tocalculate the difference. If unspecified and the current setupis a difference measurement, then this difference setup isused, otherwise it defaults to Channel A-A.MEAS1:DIFF:REL? DEF,3,(@1),(@1)Queries the CALCulate1 relativedifference measurement ofChannel A – Channel A, using the currentrange and a resolution setting of 3.
