Norsonic nor1256, Instruction Manual

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2 Nor1256
Sound Calibrator
Using the sound calibrator
• Switch on the sound level meter to be calibrated
and let the meter stabilize before calibration. A
typical sound level meter needs at least 3 minutes
to stabilise.
• Place the microphone of the sound level meter
to be calibrated in the coupler of the calibrator.
Use a suitable adaptor, if necessary. Use a slow
movement, since a fast movement may create an
excessive pressure which temporarily may change
the sensitivity of the microphone.
• Press ON/OFF button. Wait for the LED above
the “ dB -button” to change from red to green. The
level and frequency is indicated in the display of
the calibrator. After powering the sound calibrator,
the fi rst combination of frequncy level is 94 dB re.
20µPa and 1 kHz. Select the appropriate level and
frequency for your calibration by pressing the
dB or
Hz button, respectively.
• Normally the background level should be more
than 20 dB lower than the level from the calibrator
in order to not infl uence the reading. Therefore it is
good practice to notice the indicated sound level
before the sound calibrator is switched on.
Display
LED
Change level
ON/OFF
Environmental
Acoustic coupler
Battery compartment
Adapter
Calibration button
Change frequency