Frequency evaluation of A/C-curve
The frequency evaluation for the measured signal is done using two evaluation curves.
Curve A represents the characteristic hearing curve of the human ear. Lower sounds seem
quieter than middle or high frequency sounds to the human ear.
Curve C evaluates this frequency range linearly and without a filter (actual sound level).
Press the „A/C“ button to switch over to this filter. The active filter is shown in the display by
„dBA“ or dBC“.
Switching-over the measurement range between Hi/Lo
The sound level detector has two overlapping measurement ranges. The lower, Lo-range is from
30 to 100 dB and the higher, Hi-range is from 60 to 130 dB.
„OVER“ is shown in the display if the level falls below or exceeds one of these ranges. In this
case, switch-over to the lower/higher range.
Press the „Hi/Lo“ button to switch between ranges.
FAST/SLOW time evaluation
The signal can be measured using two different measurement intervals.
The time evaluation must be set to „FAST“ for sound levels that change rapidly (horns, shots,
etc.).
The time evaluation must be set to „SLOW“ for constant sound levels and sound levels that
change slowly (white noise, hums, etc.).
Press the „F/S“ button to switch between ranges.
10. Making measurements
Make sure you have suitable ear protection for loud sound sources. There is risk of an
damage to the ears!
Observe the permissible ambient temperatures (Techn. Data) to avoid faulty
measurements.
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