Setting video bandwidth spectral measurement

Hello, I am a german intern (please do not look on my grammar!) in a US company and my last weeks consisted of playing with arrays, clusters and tab controls to set up a new design for a control panel in LabVIEW. So, I am a real beginner in using LabVIEW.
My next task is to build an individual spectrum analyzer with different functions. Our Hardware: NI 5600 Downconverter, 5620 Digitizer, 5610 Upconverter, 5421 AWG. Software: LabVIEW Full 7.1, Spectral Measurement Toolkit....
I was really impressed to find this great amount of examples for perfoming spectral measurements. And I think I will try to mix a few examples and make later a few changings to get my own analyzer.
My question concerns the following: is it possible to set the sweep time and video bandwidth like with an ordinary spectrum analyzer.
Do I have to create a special vi or is there an earsier way for such individual settings.
Thank you very much for all answers.
Norbert

I'm not sure that what you are looking for is valid. In the standard "traditional" spectrum analyzer a narrow bandwidth variable frequency filter is swept across the band of interest, but when you are doing it digitally you basically are getting everything and then using an FFT to resolve, from the complex waveform received, the components that make up that waveform. Usually the only filtering is to limit the maximum frequency to below 1/2 of your sampling frequency to prevent aliasing (Nyquist theorem) Similarly, I'm not sure what in the FFT realm cooresponds to "video bandwidth" on your Agilent or Rhode & Schwarz Spectrum Analyzer. The width of your FFT's bins, which might be coorespondent, is related to the sample rate/sec and the total number of samples (which needs to be a power of 2), i.e. sampling at 11025 samples/sec, analyzing a sample set containing 8196 produces 11025/8196 = 1.35Hz wide bins. Now cooresponding with the sweep time on a SpecA the time needed to collect those samples would be #S* period, or #S*(1/fS) = 8196*(1/11025)= 0.743Sec. The more samples (higher resolution, narrow bin widths) the longer "the sweep".
P.M.
Putnam
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Senior Test Engineer
Currently using LV 6.1-LabVIEW 2012, RT8.5
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"CherieC" <[email protected]> a écrit dans le message de news:
[email protected]...
>I installed NI-RFSG, NI-RFSA, the Spectral Measurements Toolkit, and the
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>re-installing the toolkits, but this is not fixing the problem.  How
>can I get the installer to install the toolkits for both versions of
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>  
> Thanks for your help,
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