I updated fbins to version 4.0a to include a spectrum
plotting function

 http://78.46.38.217/fbins3.html

Draw a measurement box over the spectrogram and you
have a 'Plot Spectrum' button.

You can use this to examine signals in extreme narrow
bandwidth, down as low as 1uHz where you can see Doppler
effects.

To save spectrograms and plots, just use the browser's
'Save Image As' function.

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Paul Nicholson
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