Larson Davis 831, User Manual

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Model 831 Manual Performing the Measurement 7-13
Modified Profile Graph
After a back erase operation has been performed, the sound
level profile graph will be modified to indicate the erase
operation as shown in FIGURE 7-11.
FIGURE 7-11 Modified Profile Graph
Time History Records
The time history records from the point data were restored
from to the last record will be marked as back erase records.
Resetting the Measurement
A measurement is most often reset
when a noise event which is not
typical of the measurement desired
takes place. For example, an aircraft
passing overhead when attempting
to measure the background noise in
a normally quiet area. To reset a measurement in progress, press the
1
(RESET)
key. This will erase all data previously measured and reset
the run time clock to zero. A reset will not reset stored data
files. A reset can be initiated when the Model 831 is running,
paused or stopped. However, it must be stopped for the reset
operation to be performed.
Resetting When Running or Paused
If it is running or paused when the
1
key is pressed, a Stop
Required Menu will be displayed as shown in FIGURE 7-
12.
FIGURE 7-12 Stop Required Prompt
Erased Portion
of Profile