Tektronix RSA6100A Series, Help Manual

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RF Measurements > Common Controls for Settling Time
Displays Time Params Tab for Settling Time Displays
Time Params Tab for Settling Time Displays
The Time Params tab is used to set the Measurement length and minimum settled duration parameters.
Measurement Length
Measurement length locates the end of the measurement period for settling time. This value is set
independently of the analysis period for other measurements in the analyzer. This allows other
measurements to display multiple frequency hops during an analysis, while focusing the settling time
analysis on a single hop. You can set the measurement length either by entering a value in the entry box, or
by dragging the magenta bar to the desired location in the graph. Traces and the display to the right of
the measurement time are shown in grey to indicate that this section of the waveform is not being used
in the measurement. If your signal does not settle to within your tolerance band, make sure that the
measurement time ends during the settled portion of the waveform. The beginning of the settling time
measurement is set with the analysis offset control, the same as other measurements in the instrument.
Use analysis offset to exclude earlier hops from the measurement. See
Analysis Time (see page 296)
for setting the analysis offset control.
If there is more than one phase or frequency hop in the signal to be analyzed, use the Measurement Length
control to instruct the analyzer which hop to measure. First, adjust the main Analysis Offset control to a
point in time slightly earlier than the transition you wish to measure. Do this in the Time Overview display
or the Analysis Settings control panel. Then adjust the Measurement Length so the end of the Settling Time
measurement falls within the apparent settled period after the signal transition. The reason it is important
for the user to set this control is that the Settling Time measurements start at this point and look backwards
in time (towards the signal transition) to
fi nd the latest trace point that is not inside the tolerance band.
NOTE. If your signal does not settle to within your tolerance bands, make sure that the measurement time
ends during the settled portion of the waveform.
Min Settled Duration
The minimum settled duration is the amount of time the signal must remain within the tolerance band to be
considered settled. Some user speci
fi cations require that the signal be settled for a minimum period. If this
is not required in your application, set this value to the default of 0 seconds.
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RSA6100A Series Real-Time Spectrum Analyzers Help