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Using LabView 8displaying multiple ftt formats onto one graph

Using LabView 8
I am using several FTT analyzers (Hamming, Blackman, Flattop) from one signal source.  Each of the analyzers will then be displayed onto the same wavefrom graph with all the same Xo and dX.  I created a bundle for the waveform to accept Xo, dX and the Y coming from the Peak signal of the spectral analyzers.  The Y works if i only use one Peak signal, but i was hoping to be able to use multiple signals.  What i've noticed so far is that the source signal first must be converted from an array type to a dynamic data type.  This goes to the input of the FTT analyzers.  The Peak output then must be changed back to an array format so that it can be used for the Y on the bundle with Xo and dX.  When i merge the three Peak outputs to be changed to an array and then sent to the Y, there are no errors produced.  What happens though is that only one graph is produced and the Xo and dX scales are not correct.  The Y axis produces either ONE straight line or ONE triangular shaped lines, nothing near peak outputs.  My question is, how do i merge the arrays properly so that the waveform graph can display the 3 seperate lines?
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It sounds like perhaps your conversion function(s) are not configured correctly. The dynamic data conversion functions are express VIs, which means that you can double-click them and configure them. The default configuration is to convert the dynamic data to a 1D array, but If you have multiple signals merged together, then this is not the correct conversion. Instead, you should convert it to a type that accomodates multiple signals, and in your case, I think a 1D array of waveform would be best. You can then edit the t0 and dt components of each of those waveforms (since they are just default values) to be what you're looking for.

Kind Regards,

E. Sulzer
Applications Engineer
National Instruments
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