User`s manual

Table Of Contents
Audiomatica Srl FFT - 1/3 OCTAVE 10/07/01 18.07.43
CH A dBSPL 51.2kHz 16384 Rectangular File:
100 1k 10k 20k100 Hz
80.0
dBSPL
70.0
60.0
50.0
40.0
30.0
CL IO
Figure 9.6
9.7 TIME DATA DISPLAY (OSCILLOSCOPE)
The time data (Fig. 9.7) is an ancillary display to an FFT or RTA executed
measurement. Here we see a 100Hz sinusoid captured and analyzed with a 16K
FFT.
Figure 9.7
The time data display has a number of particular features that allow, out of user
control, for automatic scale adjustment and triggering of the displayed signal.
The time information displayed is the processed data only. The user can zoom in
and out of this data but it is not possible to display more than one acquisition area.
Fig. 9.8 shows this effect; the same 100Hz sinusoid as before seems now
truncated; this means that we only reached the maximum displayable data, in case
of a 16K FFT @ 51200Hz sampling this is exactly 320ms.
108 9 FFT, RTA AND “LIVE” TRANSFER FUNCTION