Hello St Augustine, Unfortunately, I cannot open these files that you have attached so I cannot tell you for certain where your problem lies. However, if you are using one of the FFT VIs from the Analzye>Waveform Measurements sub-palette, then you should be able to wire directly from the VI to a Waveform Graph. Make sure you are trying to wire to a Wavform Graph not a Waveform Chart. If you are using the FFT VIs on the Analyze>Signa Processing>Frequency Domain sub-palette, you should also be able to directly wire into a Waveform Graph, but please refer to the KnowledgeBase document linked below for more information about plotting complex numbers.
http://digital.ni.com/public.nsf/websearch/C010A823CEA80D5386256938005A066E?OpenDocument Regards, Jyoti F National Instruments
