HBK 4231, User Manual

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Adapters
4 Sound Calibrator Type 4231
User Manual
1.5 Adapters
Sound Calibrator Type 4231 is mainly intended to be used when
calibrating instruments with 1

and 1/2

microphones. With other
adapters, you can also use the calibrator for calibrating the
microphones and instruments shown in Table 1.1.
With some adapters, the calibration level and uncertainty may be
affected and you must manually add or subtract the stated calibration
level correction to compensate for this.
1.5.1 Calibrating 1

Microphones
To calibrate a 1

microphone, take the calibrator out of the case and
remove the green 1/2

adapter (UC 0210), which is supplied with the
calibrator, by twisting it about 1/8 of a turn anti-clockwise as shown in
Fig.1.2. Then fit the microphone into the 1

opening underneath.
Fig.1.2 Removing the 1/2

adapter