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SVANTEK 977W User Manual
The
Logger Name
position enables the
user to define the name of the logger file in
which the data of the
RT60
analysis will be
recorded. The name can be up to eight
characters long. After pressing the
◄ or ►
push-buttons, the special window with text
editor is opened.
►
The
Level
position defines the level for triggering the measurement.
In the
Impulse
method, the trigger condition appears when the
TOTAL
sound
pressure level exceeds the defined by the user threshold
Level
value. The
parameter can be set in the range
24
÷
136
dB
with
1 dB
step (
100 dB
default
value).
In the
Decay
method, the
Leq
level defined by the
Level
parameter must be
reached to start time history recording. The
RT60
measurement starts when the
1 second
Leq
(
A
weighted) level value decreases by
10 dB
. The RT60 Decay
algorithm uses 50 samples pre-
trigger, defined by “10 dB drop point” (see
Appendix H).
13.3. Setting the RT60 view
The
Display Modes
list of the
Display
menu enables the user to select the type of
data displayed during the
RT60
calculation.
<ENT>
Time data can be viewed as a
Raw Data
,
Smoothed Data
(or
Integrated Data
in case of
Impulse
method).
The user may also switch between different data view modes during measurement in the presentation display
mode. For this purpose, it is necessary to set the cursor on the field with
Raw
,
Smoothed
or
Integrated
text
(at the right upper corner of the display) and change its content with the
<Alt>
and
◄ or ► push-buttons.
<Alt/
►
>
<Alt/
►
>
13.4. Start RT60 measurements
Measurements with the use of Decay method
1.
Set parameters for
Decay
RT60 measurements. Most used setup is
presented below.
Method:
Decay
Recording Time:
7s
Time Step:
10ms
Averaging:
On
Smoothing:
3
