Re: Dumb FFTquestion

On Tue, 23 Oct 2007 17:00:46 -0700, in sci.electronics.design Genome
<mrspamizgood@xxxxxxxxxxx> wrote:

On Oct 23, 11:28 pm, Martin Griffith <mart_in_medina@xxxxxxxx> wrote:
I'm doing some sims in LTspice, that take a long time, 30+
minutes...so if I just sample say 20mS, using the Mr Blackman's
window, at what LF should I ignore the results?

Truthiness makes me want to think that it is 100Hz, but the plots are
deceiving me

Martin

Bum.... you only have to do that windowing stuff if you don't pick a
start and end point on the waveform that does not make it wrap around
and agree with itself coming up the other side afterwards.

Go look at when you want it to start and when you want it to end and
then tell the FFT what those are without the windowing.

DNA
didnt understand a word of that :-(


Martin
.

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