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The quetion about sound card output to Oscilloscope

Hi all !I found a problem :I use labviewI created a digital square wave form to Export to  Oscilloscope,and remove The while loop(use finite samples) ,and Display images below,my sound card Default Sample Format:samples rate :22050;16 bits  per samples;I took the  data points in The  vi ,(vi,Classification of data points iData points n the graph below),

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I don't see what your problem is.  What is that spreadsheet about?  You put the image over top of the text.


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thanks for your reply!I created a square wave in labview use numbers,and This signal is then output from the sound card to the oscilloscope,my vi in 2.png and 3,png; spreadsheet ’data points is the green line marks the data point selection in 3.png  ,The other part in the spreadsheet  is the part marked in red 2.png;My reason for doing so:I chose the 1336 points , theoretically converted into 167 waveforms, we can clearly see the waveform chart display in 2.png, I will signal input to the oscilloscope , but can only display 11 waveforms , I only can change Computer sound card sampling rate to increase the number of waveform ,roughly law I made ​​an spreadsheet,

 I can not understand is the calculation I reached the limits of the sampling frequency of the oscilloscope waveform is not more than 30 , but according to the median of 16 in terms of sound , namely rate of 2 ^ 16 , so much resolution, should at least see hundreds or even thousands in the oscilloscope waveforms , but actually not the case , I do not know where the problem is , I hope you can give suggestions , thank you!
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What oscilloscope are you using?  What timebase do you have it set to?

 

At the 60kS/s, you are sending out about 22ms of data.  Make sure your scope is setup to capture at least that.

 

The other issue could be that you are closing your sound card before it has finished writing the waveform to the output.  Try adding a wait after the Sound Output Write VI.


GCentral
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"Not that we are sufficient in ourselves to claim anything as coming from us, but our sufficiency is from God" - 2 Corinthians 3:5
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I'm sorry to reply so late! my scope is tektronix TDS 1002,Display parameters:60MHZ,1GS/s,I have access to relevant information , learn 1GS / s corresponding data points have 50000000 points for my SCOPE,And I use labview own example : general sound vi, remove the while loop , the waveform display is still the same as before , section by section , each section is only five sine wave ( each sine has a 100   data point  ),how it happen ?any Proposal will be great help ,thank you!

 

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