National Instruments NI 9233 User Manual

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NI 9233 Operating Instructions and Specifications
10
ni.com
The NI 9233 also has TEDS circuitry. For more information about 
TEDS, visit 
ni.com/info
 and enter 
rdteds
.
Understanding NI 9233 Filtering
The NI 9233 uses a combination of analog and digital filtering 
to provide an accurate representation of in-band signals while 
rejecting out-of-band signals. The filters discriminate between 
signals based on the frequency range, or bandwidth, of the signal. 
The three important bandwidths to consider are the passband, the 
stopband, and the alias-free bandwidth. 
The NI 9233 represents signals within the passband, as quantified 
primarily by passband flatness and phase nonlinearity. All signals 
that appear in the alias-free bandwidth are either unaliased signals 
or signals that have been filtered by at least the amount of the 
stopband rejection.
Passband
The signals within the passband have frequency-dependent gain or 
attenuation. The small amount of variation in gain with respect to 
frequency is called the passband flatness. The digital filters of the 
NI 9233 adjust the frequency range of the passband to match the 
data rate. Therefore, the amount of gain or attenuation at a given