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The calibration will be performed at the selected level e.g. 94.0dB but may be
changed in 0.1 or 1 dB steps using the following keys: -
Key
Calibration Level
Adjustment (dB)
+0.1
-0.1
i
-1.0
/
+1.0
Ensure the calibrator is attached to the microphone by gently inserting the
microphone into the cavity of the calibrator. A certain amount of resistance
should be felt whilst inserting the microphone as the o-ring seal on the calibrator
forms a seal around the microphone.
Ensure that the calibrator is switched on and set to the chosen level and all
correction factors for atmospheric pressure and microphone type have been
accounted for.
The pressure to free-field correction value to be applied when used with a Castle
calibrator GA601, GA607, or a B&K4231 is as follows:
Calibrator
Correction (dB)
Castle GA607
-0.2
Castle GA601
-0.2
B&K4231
-0.2
Press
and the instrument will calibrate to the level of the calibrator. The
display will show
CAL WAIT
while calibrating to the chosen level. When
calibrated the display will show
COMPLETE
and
will return to the Sound
Pressure Level display.
It is recommended that the unit is then placed into
STOP
mode and data is
cleared. The instrument is now ready to take measurements.
If the calibration is interrupted or the input level is not /- 3dB of the
chosen reference level then the display will show
CAL FAIL
.
An error message of
NO INPUT
is shown if the input level is lower than
approximately 70dB.
Check to make sure the calibrator is switched on and emitting the correct level
before proceeding again as indicated above.
OK
