Tektronix RSA6100A Series, Help Manual

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General Signal Viewing > Common Controls for General
Signal Viewing Displays Prefs Tab
use the POI time value to determine if you are at risk of either missing a narrow transient or of its
captured amplitude being less than the actual signal.
Minimum signal duration vs. RBW, option 200
Span RBW (kHz) FFT length Spectrums/s
Minimum signal duration for
100% POI,
μ s
1000 1024 292,969 5.8
300 2048 146,484 14.8
100 4096 73,242 37.7
30 16,384 18,311 134.8
110 MHz
20 32,768 9,155 229.5
1000 1,024 292,969 5.8
300 1,024 292,969 11.4
100 2,048 146,484 30.9
30 4,096 73,242 107.4
20 8,192 36,621 147.4
40 MHz
10 16,384 18,311 294.8
xxx
Transforms/s – This is the number of transforms/second being performed by the DPX engine.
It is a function of the selected resolution bandwidth and number of trace points. The desired
RBW determines the number of points required in each transform, which alters the transform rate.
Additionally, the selected trace length may place requirements on the number of points required in
the transform independent of the selected resolution bandwidth.
FFT Points – The approximate number of points in the FFT of the input signal. FFT points provides
an indication of frequency resolution, but it is not an exact measurement. Note that higher numbers
for FFT points mean that the instrument is taking a longer string of input samples for each FFT,
which decreases the time resolution.
Minimum FFT length versus trace length (independent of span and RBW), Option 200
Trace length (points) Minimum FFT length
801 1,024
2,401 4,096
4,001 8,192
10,401 16,384
xxx
RSA6100A Series Real-Time Spectrum Analyzers Help
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