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Oscilloscope + Labview oscilloscope driver + Labview = Bode Plot

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Hello. 
Maybe someone knows how to create a Bode diagram in Labview with an oscilloscope signal? I downloaded the driver for my oscilloscope to work with Labview. If you know how to do that, please take a photo with instructions.
https://www.youtube.com/watch?v=IVFFyj-U7Jo&feature=youtu.be&t=37 Oscilloscope data sheet https://mediacdn.eu/mage/media/downloads/SDS1000X-E_datasheet.pdf Labview driver for the oscilloscope https://www.siglent.eu/Downloads In Tektronix oscilloscopes, Bode Plot can be executed via Signal Express. Unfortunately, I do not have a Tektronix oscilloscope.

 

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Message 1 of 8
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A Bode Plot is just a frequency response curve, right?

 

As you sweep through the frequency range take measurements with the scope at regular intervals and plot those measurements on an X-Y graph with frequency in the X- Axis and amplitude in the Y-Axis

 

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Unfortunately, most readers of this Forum, including some real Experts, have not mastered the skill of being able to read the code that Posters fail to post. If we cannot see "what you did wrong", we are unable to tell you how to fix it. (Bob Schor 28 August 2018)
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Message 2 of 8
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You can't create a Bode plot with just an oscilloscope.  You also need a cyclical signal of some kind (usually a sine wave) and a way to sweep it through a frequency range. 

You can use LabVIEW to simulate the whole process though.  Here's an example of sweeping a sine wave to measure a filter response and viewing the results as a bode plot:

https://forums.ni.com/t5/Example-Programs/Bode-Diagram-Plot-Using-LabVIEW/ta-p/3504314

LabVIEW 8.5.1 - 2018 Pro Dev
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Message 3 of 8
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 RTSLVU, this method will not give an exact result. Bode Plot(Frequency response) is better.


NIquist; Yes, I need something like that.

To generate a sweep signal, I use a signal generator. https://mediacdn.eu/mage/media/wysiwyg/siglent/Downloads/DataSheet/SDG1000X%20Datasheet-en.pdf
The oscilloscope is connected to a computer. On the computer, LabView with a driver for my oscilloscope. How to embed Bode Plot in my LabView driver so Labview uses signals from my oscilloscope and creates a Bode Plot?

https://www.youtube.com/watch?v=UmTAhIrVids On the video in the oscilloscope there is the Bode Plot function, I do not have such a function in the oscilloscope. Therefore, I need a computer and LabView for this.

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Message 4 of 8
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For a transfer function you should know the exitation or measure it Smiley Wink  (and the response ...),

if you have simultaniously captured both signals (your scope has at least two channels Smiley Very Happy) , you can use the math or signal processing vis to calculate the transfer function (usually you have to decide wether you do it mainly in time or frequency domain ... )

Wether you use a stepped sine, multi sine, noise, chirp ....  is up to your needs and programming skills.

 

To analyse potential differences between the two channels, just swap them Smiley Wink  (and use both data and the geometric! mean)

 

Greetings from Germany
Henrik

LV since v3.1

“ground” is a convenient fantasy

'˙˙˙˙uıɐƃɐ lɐıp puɐ °06 ǝuoɥd ɹnoʎ uɹnʇ ǝsɐǝld 'ʎɹɐuıƃɐɯı sı pǝlɐıp ǝʌɐɥ noʎ ɹǝqɯnu ǝɥʇ'


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Message 5 of 8
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@monopolie wrote:

 RTSLVU, this method will not give an exact result. Bode Plot(Frequency response) is better.

 

 


Sure, you will need to do some processing but the method of measuring the output with the oscilloscope, processing and plotting it in an X/Y chart is exactly what everyone else is telling you to do.

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Unfortunately, most readers of this Forum, including some real Experts, have not mastered the skill of being able to read the code that Posters fail to post. If we cannot see "what you did wrong", we are unable to tell you how to fix it. (Bob Schor 28 August 2018)
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Message 6 of 8
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Electronics is my hobby. A thousand apologies, I did not understand something about how to make X / Y Bode Plot.
I made a Bode Plot (not an X / Y Bode Plot) using a signal generator and an oscilloscope (image 1).

RTSLVU, How to take measurements with an oscilloscope at regular intervals on this Bode plot (image 1)? Maybe this is done using programs such as Matlab, and the analysis should be done on a computer? On my oscilloscope I did not see such a function that it was possible to take measurements at regular intervals.

On my oscilloscope, measurements can be taken at regular intervals only using cursors (image 2).
What result should I get I understand:  frequency in the X- Axis and amplitude in the Y-Axis. I do not know how to do this.

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Message 7 of 8
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I don't know what oscilloscope you are using but every scope I have used with LabVIEW that could do on screen measurements cold also do the same measurements remotely using LabVIEW.

 

 

 

  

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Unfortunately, most readers of this Forum, including some real Experts, have not mastered the skill of being able to read the code that Posters fail to post. If we cannot see "what you did wrong", we are unable to tell you how to fix it. (Bob Schor 28 August 2018)
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Message 8 of 8
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