# Get the value of the frequency of the power spectrum

I'm rather new to LabView and want to measure the frequency of the peak in a spectrum of power of a real signal. In addition, I want this value of frequency and amplitude to save to a file. Right now I am able to trace a spectrum of power using an express VI, which gives me the correct frequency value in the graph.

However, I'm not able to extract the value of the frequency with different screws, I found in LabView after browsing through the various discussions in this forum. Can someone tell me please in the right direction? I use a digitizer NI PXI-5124 to record the signal in a rack of NOR.

If it is the dominant frequency you are looking for you can use the vi extracted a single signal. You can also change this vi to include the details of the search if it isn't the dominant frequency, I have not included it in my example, but you can check it in the help file.

Ian

Tags: NI Software

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========================================================

These are the resources of the United States and it should be similar for Microsoft India.

XBox - Support<-- best="">
http://support.Xbox.com/en-us/pages/default.aspx

http://support.Xbox.com/en-us/contact-us

XBox - Support Forums - and my XBox (top-right)<-- might="" be="" some="" good="" information="">
http://forums.Xbox.com/

Xbox technical support phone number

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I hope this helps.

Rob Brown - Microsoft MVP<- profile="" -="" windows="" expert="" -="" consumer="" :="" bicycle=""><- mark="" twain="" said="" it="">

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SignalExpress is programmed to display graphs with default scales based on the type of action, it's reading. These scales and settings can be changed by right-clicking on the graph, and then select Properties.

If you are interested to learn more about how to use SignalExpress, I would recommend checking out some demonstrations/tutorials on NI.com. You can find some of these demos at the following location:

Let me know if you have any other questions.

Kind regards

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Hi, I'm Jean,

I traced xy graphic for an excel file.

I converted excel file in text file and saved as a .lvm file. now I need to find the fft for this xy graph.

I will attach my text files and my vi.

Please, someone put the program and send me quickly.

I need urgent...

Here is a simple way to resample the data for a linear ramp of x and make the power spectrum. Modify if needed. (LabVIEW 2011)

(Fortunately you don't need to worry about the artifacts because each spectral component contains a whole number of cycles in your data)

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I am beginner in labview, I want to see the power spectrum of the sound samples, I want to see if there is any reason in these samples.

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I've tried to filter using these values (fs = 1000 Hz, 0.125 hz = fl and fh = 500 hz) and the graphics almost the same thing but the axis of the graph is between 0-0, 5.

issues related to the:

What is the x axis properties? Why is different, but the graphics are the same?

Make the mistake with the program?

Hi Limavolt,

You have a problem with the bandpass filter VI, this VI generates only the signal of value i.e. table DBL. The signal is a cluster.

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How can I trust the result of 512Hz on?

I've attached screenshots of:

(1) my application project configuration

(2) result of frequency domain

Very useful information, thanks to you both for helping!

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