Dynamic Signal Acquisition

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how can i acquire signal magnitude per every 0.2hz using pxi 4472

hello

i am using PXI 4472 card for FFT
analysis using LabView2009

i need to acquire the frequency Vs
magnitude for my application

Can anybody help me out to get
voltage magnitude for every (df)0.2Hz up to 500Hz bandwidth.

i could acquire the Voltage
magnitude for every (df)0.5hz,

with configuration continuous mode of 1000 sample
rate and 1000 samples per channel and spectrum measurement Express VI with

2000msec
delay time (‘df’=0.5Hz=1/2000mSec), further less ‘df’ program is terminating
intermittently

Please give your suggestion

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Here is a good rule of thumb:

 

Frequency Span = 0hz to sample rate divided by 2.56

lines of resolution =  record block size divided by 2.56

 

for example a 1khz sample rate and1k darta points is a 0 to 400hz spectrum (401 to 512 is calculated by not fully trusted in machinery world) and 400 bins or one bin per hz, df = 1. 

 

so for this example if you need df to be 0.2Hz, you need five times as much data or 5000 data points. 

 

 

Preston Johnson
Solutions Manager, Industrial IoT: Condition Monitoring and Predictive Analytics
cbt
512 431 2371
preston.johnson@cbtechinc
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