Hioki MEMORY HiCORDER 8855, Instruction Manual

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4.3 STATUS Settings (FFT)
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4.3.5 Setting the Window Function
Function
display Meaning
: Rectangular (effective on discrete waveforms)
: Hanning (effective on continuous waveforms)
: Exponential (effective on decaying waveforms)
Function
display Meaning
: Increases in number, small step
: Decreases in number, small step
100%
100%
Waveform captured
in one operation
10%
10%
Noise on attenuated waveform
is reduced
When setting of exponential window function
attenuation ratio 10%
NOTE
The window function defines the segment of the input signal that will be
processed. Window processing can be used to minimize leakage error.
Screen: STATUS, Waveform display
Procedure 1. Use the Menu keys to display the desired screen.
2. Move the flashing cursor to the
Window
item.
3. Use the function key to make the selection.
4. If
EXPO.
was selected, the coefficient item is displayed. Select the
attenuation ratio in percent, using the function keys or the Jog/shuttle
controls. If coefficient (attenuation ratio) is set to 0%, processing will be
carried out as 0.1%.
When measurements are taken using the Hanning window or exponential
window, note that the calculation results in the display of a value that is
lower than the amplitude obtained when using a rectangular window.