Spectral Measurements Toolkit + subtracting one waveform from another

[Dntblnk22]

I am trying to determine whether it is possible to use the Spectral measurements Toolkit to capture 2 waveforms and subtract one from the other to see the difference. 

Any advice here would be greatly appreciated.

Thanks

[MicrowaveDave]

Hey,

From your description, it sounds like you might not need the spectral measurements toolkit at all.  If you can acquire two waveforms (either with the DAQmx or NI-SCOPE drivers), it is possible to simply subtract the difference with a LabVIEW numeric subtract function.  These functions (add/subtract/multiply, etc.) are polymorphic, which means that they can add, subtract, or multiply many different types of data.  Thus, just as they can operate on two numbers, they can also operate on two waveforms as well.  Thus, I would try use the numeric add function.  Hope this helps and let me know if you have any more questions!

Regards,

David Hall | Applications Engineering | National Instruments

[Dntblnk22]

Hi David,

Thanks for the prompt reply.  I am very new to this hardware/software so please let me know if I am going down the wrong path.  The software I am working with was previously written to capture a waveform using a NI 5122 Digitizer.  I was thinking that I would like to capture that same waveform on one channel of that digitizer directly and also capture it again after it has gone through the rest of my system starting with the other channel.  Then subtract the first from the second to measure the difference. 

So you're saying that the Spectral Measurements Toolkit is not necessary for this measurement?  I will investigate the NI Scope drivers as you had mentioned. 

Please let me know if you think I am headed down the wrong path. 


Many thanks for your prompt response.


Tony