Spectral analysis of an acquired signal

Hello there,
I am trying to acquire a signal for spectral analysis. I have set the analog input VI to 1Chan/NSamp/Dbl format, and fed the data to the express spectral analyzer VI. The VI is set to acquire arrays of 100 samples length, before feeding it to the FFT VI. The problem is, however, that the waveform graph I use to present the spectral distribution shows spectral analysis for a bandwidth of 0.5 Hz only (0 to 0.5 Hz), and I have no clue why this happens. I am sure there is something I do not know about how to set the application to go right.
P.S. I have also tried the low level FFT VI, the wavegorm graph shows a bandwidth corresponding to the number of samples being acquired at each iteration, (100 in my case), which really confuses me. I have looked at the examples, and none of them uses DAQ for FFT, they all use signal generators which work fine with me.
Does anyone have an idea of what I am doing wrong, any help shall be greatly appreciated...
Thankyou for your patience,,,
Bedair

Hello there,
Attached is a sample code of my problem, please note that I use LabVIEW 8.0
Thank you for your help,,,
Bedair
Attachments:
sample_code_fft_noise1.vi ‏86 KB

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Sssantosssh wrote:
How does one acquire the physiological signals from a medical monitor? The monitor is a non-national instruments monitor. The patient monitor records ecg, invasive blood pressure from a patient and displays this on a screen. This information is relayed to a central station. Is there a way to obtain these signals and see the ecg and blood pressure waveforms in labview and thus analyse these waveforms. Thank you
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Spectral analysis of an acquired signal

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