PeakTech 1280 Bedienungsanleitung Seite 88

1. Click to show Function menu, choose "Math". Check "FFT". The user interface is
switched into Three View mode.
2. Set "Channel", "Window", "Format", "Scale", "Frequency Base".
3. You can drag anywhere in FFT window to move the signal up and down and side to side.
15.1. To select the FFT window
There are four FFT windows. Each one has trade-offs between frequency resolution and magnitude
accuracy.
Type
Hamming
Rectangle
Characteristics
Better solution for magnitude
than Rectangle, and good for
frequency as well. It has slightly
better frequency resolution than
Hanning.
Recommend to use for:
Hamming
 Sine,
periodic and
band random noise.
 Transients or bursts where the
signal levels before and after
the event are significantly
different
Best solution for
worst for magnitude.
Best type for measuring the
frequency spectrum
repetitive signals and measuring
frequency components near DC.
Recommend to use for:
 Transients
or bursts,
signal level before and after
the event are nearly equal.
 Equal-amplitude sine waves
with frequencies those are
very close.
 Broadband random noise with
a relatively slow
spectrum
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Window
narrow
frequency,
of non
the
varying