SubSurface Instruments LD-18, Руководство по эксплуатации

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7. Method for use in correspondence to situation of the field
<Filter selection>
(1) In a place where undesirable noise such as electric pole transformer sound, commercial frequency sound
from automatic vending machines, passing sounds from pedestrians’ and automotive vehicles and barking
dog is excessive, it is possible to more positively pin down the target sound when a combination of
BPF+NF+NR processing is applied.
(2) In a place where undesirable noise such as passing sounds from pedestrians’ and automotive vehicles and
barking dog is excessive, it is possible to more positively pin down the target sound when a combination
of BPF+NR processing is applied.
(3) In case the level of undesirable noise is low in suburbs or the like, it is possible to pin down the target
sound with BPF alone.
Each pipe generates its own leak sound within a certain range of frequency according to the material of pipe.
The following examples would be convenient to know the filtered width.
<Minimum level value>
As you get closer to the leak, the sound gets louder. Minimum level value decides which two of these loca-
tions are the loudest. Minimum level value is corrected for the changes in SENS, However, when you com-
pare it with the other site, we recommend to use the same SENS in good comparison.
[Hardware]
100Hz 200Hz 400Hz 600Hz 800Hz 1200Hz
Distribution Pipe CIP
Distribution Pipe VP
Service Pipe VP
Service Pipe GP
Pipes