Svantek SVAN 958A - FFT ANALYSER; SELECTING FFT ANALYSIS MODE; SELECTING FFT ANALYSIS PARAMETERS - FFT SETUP

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SVAN 958A User Manual
12 FFT ANALYSER
The instrument operates as the FFT analyser in a very similar way to the level meter. Moreover, the FFT
analysis is performed in parallel with the level meter measurements.
The results of FFT analysis (spectra) can be examined by the user on a
display in the Spectrum presentation mode. The availability of this mode can
be switched on or off by the user (path: <Menu> / Display / Display Modes).
FFT spectra with the single Total overall value measured with preselected
frequency weighting filter and windowing are presented in the Spectrum
mode. The read-out of the value of interest in the spectrum can be done using
the vertical cursor.
12.1 SELECTING FFT ANALYSIS MODE
In order to select the FFT function the user
has to enter the Function list by pressing the
<Menu> key, then select the Measurement
Function position and open it by pressing
<ENTER>. In the Measur. Function list the
user has to highlight the FFT option, mark it
by ► key and then press <ENTER>.
<ENT>
Note: It is not possible to change the current function while a measurement is taking place.
In this case the instrument displays for about 2 seconds the text ”Measurement in Progress”. In
order to change the current measurement function the instrument must be stopped!
12.2 SELECTING FFT ANALYSIS PARAMETERS – FFT SETUP
The execution of the FFT analysis depends on
settings made in the Measurement Setup list.
The Spectra are averaged during the period
defined by Int. Period and repeated as defined
in the Cycles Number position.
<ENT>
The FFT Setup position appears in the Input list
for the FFT function and enables the user to
select the parameters of FFT spectrum
calculation for each channel: filter, frequency
band, window type and number of spectrum
lines.
<ENT>
Activavting FFT in the channel
The activation of spectrum calculation is made by switching on ([
]) the
Enabled position.