Technical data

494 Agilent Infiniium 90000 Series Oscilloscopes Programmer's Reference
24 Measure Commands
:MEASure:FFT:MAGNitude
Command :MEASure:FFT:MAGNitude [<source>]
The :MEASure:FFT:MAGNitude command measures the magnitude of the
FFT. The source is specified with the :MEASure:SOURce command or with
the optional parameter following the :MEASure:FFT command.
The source must be a function that is set to FFT, or a waveform memory
that contains an FFT for this command and query to work.
<source> {FUNCtion<N> | WMEMory<N> | CLOCk | MTRend | MSPectrum |
EQUalized}
MTRend and MSPectrum sources are only available if the oscilloscope has
the EZJIT option installed and the feature is enabled.
The CLOCk source is only available if the oscilloscope has the High Speed
Serial option installed and the feature is enabled.
The EQUalized source is only available if the oscilloscope has the High
Speed Serial option and the Serial Data Equalization option installed and
the features are enabled. This command uses the Feed- Forward Equalized
(FFE) signal as the source.
<N> For functions and waveform memories: 1, 2, 3, or 4.
Query
:MEASure:FFT:MAGNitude?
The :MEASure:FFT:MAGNitude? query returns the magnitude value of the
FFT.
Returned Format
[:MEASure:FFT:FMAGNitude] <magnitude>[,<result_state>]<NL>
<result_state> If SENDvalid is ON, the result state is returned with the measurement
result. See the :MEASure:RESults table in this chapter for a list of the
result states.
Example This example measures the magnitude of the peak specified by the
:meas:fft:peak for channel 4.
myScope.WriteString ":SYSTEM:HEADER OFF" ' Response headers off.
myScope.WriteString ":func4:fftm chan4" ' Perform FFT on channel 4.
myScope.WriteString ":func4:disp on" ' Display the FFT.
myScope.WriteString ":meas:FFT:thr-47" ' Set peak threshold at-47 dBm.
myScope.WriteString ":meas:FFT:Peak1 2" ' Meas magnitude of peak 2.
myScope.WriteString ":meas:FFT:magn func4" ' Perform magnitude meas.
myScope.WriteString ":meas:FFT:magn? func4" ' Query for measurement.
varMagnitude = myScope.ReadNumber
Debug.Print FormatNumber(varMagnitude, "Scientific")