BRUEL & KJAER 4448 Manual De Instrucciones página 5

CalibratiOn
NOTE: By default Type 4448
is set up for a calibration level
of 94dB. You can change this
using PC Software Type 7825
Protector (for more details see
Type 7825 Online Help and
Type 4448 User Manual).
to Calibrate type 4448
1. Switch on Type 4448 and wait for it
to start up.
2. Remove windshield
(important: see windShield)
3. Place the acoustic calibrator
over the microphone as shown
to the left. Be careful to push
the calibrator straight onto Type
4448 without twisting, since this
might loosen or over tighten the
microphone capsule.
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4. Turn on the calibrator. Type
4448 automatically recognises
calibration tones and enters
calibration mode.
5. Press the 'R' key to confirm that
you wish to calibrate. Type 4448
will take a few seconds to automat-
ically adjust to the required level.
Once calibration is completed, a 'CAL
OK' message will appear. Type 4448
stores the calibration date, time and
level then returns to the default
screens.
windshield
to remove the windshield
Twist the black plastic ring
(not the foam) counter-
clockwise and lift it off.
to attach the windshield
Place the tabs into the slots
then gently twist the black
plastic ring (not the foam)
clockwise.
NOTE: When attaching or removing the windshield always hold and twist using the
black plastic ring at the base of the windshield: Never use the foam.
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