Hello, It sounds like you've sorted out your questions through the two excellent response posts.
I found a couple of knowledge base entries regarding FFT analysis in LabVIEW, and I thought you may want to reference them for further information/instruction. Please look at the following links. http://www.ni.com/support/labview/toolkits/analysis/analy3.htm http://digital.ni.com/public.nsf/3efedde4322fef19862567740067f3cc/eb86c3f027df072186256db0006c3612?OpenDocument I hope this helps. Please let me know if you still have any questions. Have a great day! Kind Regards, Joe Des Rosier National Instruments