Larson Davis 831C-FFT, Справочное руководство

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SoundAdvisor Model 831C Making the FFT Measurement 145
FIGURE 18-7 FFT Misc tab
d.
Select up to 3
Trigger Sources
from the drop-down menus, and
enter up to 3 Trigger Levels .
e.
If your Transducer is a microphone,
integration is disabled. If you
selected Other as the transducer,
select an option from the
Integration drop-down menu.
LEARN MORE
For more information on
each integration option, look for the
terms in Appendix C Glossary on
page 1
.
Step 14.
If you’re using a microphone, press the right softkey (
//*
) to set values on
the Tonality tab. If you’re using another transducer, skip this step.
a.
If desired, select a Tonality standard from the Tonality drop-down menu.
FIGURE 18-8
For ISO 1996-2 tonality:
the measurement
must be A-weighted, averaged for at least 1
minute, with the Hanning window applied. If
your settings differ from the selected standard,
the 831C displays a prompt from which you
can automatically choose standard-compliant
settings.
For ISO/PAS 20065 tonality:
the Line
Bandwidth must be 1.9–4.0 Hz, etc. If your
settings differ from the selected standard, the
831C displays a prompt from which you can
automatically choose standard-compliant
settings. Refer to the standard for other
specifics.
b.
Select other available values
according to the Tonality standard you
selected. For additional information,
look for these properties in Appendix C Glossary on page 1 ., or in the selected
standard.
Step 15.
Press the middle softkey (
/*/
) to Close and save the Setup and return to
the Setup Manager tab.
18.3 Making the FFT Measurement
Step 1.
Make the FFT measurement setup the Active Setup on the meter. To do this, do
the following: