76
Table 6-19
FFT frequency analysis
FFT operation techniques
Select FFT window
Use FFT (fast Fourier transform) mathematic
operation to transform time domain signal into
frequency-domain signal.
It is convenient to observe the following types of
signals by using FFT
Measure harmonic content and distortion
Indicate noise property in DC power
Analyze vibration
As signal containing DC component or bias will
result in mistakes or bias in FFT waveform
components, in order to reduce DC components,
you can select AC coupling. For reducing random
noise and aliased frequency components in the
repeat or single pulse event
you can set
oscilloscope s acquisition mode as average.
Suppose YT waveform is repeating continuously,
oscilloscope takes FFT transformation of the time
record with limit length. When the period is an
integral, ampliltude value of YT waveform remains
the same at thestart and finish the waveform
shall not discontinue
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UTD1000L User Manual
Function menu
FFT
Source
Windows
Vert Scal
Set
Open/close FFT
operation function
.
Select information source
involved in operation
when
it is dual channel
model
.
Set Hanning window function
Set Hanning window function
Set Blaclman window function
Set Blaclman window function
Set vertical coordinate unit
as linear or vdb
----
Hanning
Hamming
Blackman
Rectangle
Vrms
dBVrms
On
Off
Instruction
