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How to graph frequency response

I would like to sweep the input frequency, say from 550mhz to 950mhz, take the result of each sweep and plot that on a graph. But I want each plot to stay on the graph so that what I end up with would show what the  shape of a filter would look like. Actually that is what I am testing. I am sweeping a filter with a 40mhz bandwidth and looking at the output on my spectrum analzyer with infinite persistence to see the overall response of the filter. How can I implement something like that in labview.

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What is your specific question? How to perform a sweep? Are you controlling some instrument? Are you asking how to control the instrument? Are you asking about instrument drivers? Are you asking how to design the program? Are you asking how to do a user interface? Are you asking how to draw graphs? Have you looked at any of the LabVIEW tutorials? Have you looked at any of the examples that ship with LabVIEW? What exactly have you done?  There are several examples that ship with LabVIEW on how to draw graphs. For multiple graphs you'd just wire an array of data.

 

Remember, to help us help you,  How To Ask Questions The Smart Way

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Specific question: How do I draw the response curve of a filter in a graph.

I am not asking how to perform a sweep

Yes I am controlling an instrument

I am not asking how to control the instrument

I am not asking about instrument drivers

I am asking how to implement the program

I am not asking how to design a user interface

I am asking how to draw multiple graphs without overwriting previous graphs

Yes I have looked at labview tutorials

Yes I have looked at the examples that ship with Labview

I have wired the output of my data collect routine to an array an wired that to a graph. Did not get the expected result.

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@Rivetm wrote:

I have wired the output of my data collect routine to an array an wired that to a graph. Did not get the expected result.


That's not quite correct. What I mean by using arrays is that you can use arrays to draw multiple plots. For a chart an array would place an additional point for each plot, with each element of the array referring to a different plot. For a waveform graph a 2D array would correspond to the data for multiple plots. For an XY graph then you'd need an array of clusters, where each cluster contains 2 separate arrays - one for the X values and one for the Y values. Thus, how you do it depends on the type of chart/graph that you have. If you upload your code it will be easier to point out the issue.

 

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Actually, maybe I should approach this in a different way. How about I give you the data file that I have. It represents the swept data from the filter. I guess I just want to analyze this data and put it in a graph; here's what I have tried.

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I have no idea what that data is supposed to represent, and what you mean by "analyze this data". Why are you trying to perform a spectral measurement of integers?

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That data looks way more complicated than it has to be.  Why not set up your instrument for a single sweep, get the trace data and work with it?  (Trigger a single sweep for each trace.)

Bill
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