From: ImageAnalyst on
Yeah, you basically get a signal that's energy as a function of
frequency (cycles per second, Hz). I'm not sure of the exact units -
it depends on what you start with. You're starting with Volts. I'm
not exactly sure of the FFT units - maybe it's Watts or something
related to that, but I'd have to do some studying up on that. I'm
sure someone else will know and tell you.