Svantek SVAN 971 - History of Calibrations - Last Calibration; Post Measurement Calibration - Post Calibration

SVAN 971 User Manual
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After calibration measurement stop, the New Factor (difference between
Calibration Level and Calibration Measurement, calculated in dB) is displayed and
it will be proposed to save the new calibration factor by pressing <Enter>
(Enter=Conf.), or reject it by pressing <Esc>. In both cases the instrument exits
the Calibration screen.
It is recommended to repeat calibration measurements few times. Obtained results should be almost the
same (with 0.1 dB difference). Reasons for unstable results are as follows:
• calibrator is not properly attached to the instrument,
• there are external acoustic disturbances such as high noise levels nearby,
• calibrator or measurement channel (the microphone, the preamplifier or the instrument itself)
are damaged.
Note: During the calibration measurement, external disturbances (acoustic noise or
vibrations) should not exceed a value of 100 dB (when using a calibrator that generates
114 dB).
5. Press <Enter> to accept and save the new calibration
factor.
If calculated calibration factor is out of the ±3 dB range
the special warning appears on the screen. If the
calibration factor is out of the ±20 dB range the calibration
factor is not accepted.
<ENT>
6. Detach the calibrator from the microphone.
Note: To quit the calibration procedure without saving the calibration factor, press <ESC>.
4.2.2 History of calibrations - Last Calibration
The Last Cal. window displays up to ten last calibration
records and one position, that erases all calibration
records (Clear Hist.).
<ENT>
To erase all calibrations records in the history, choose the position Clear Hist.
and press <Enter>.
The instrument requests confirmation of the selected operation.
4.2.3 Post measurement calibration – Post Calibration
Sometimes it is required to perform so called post-
calibration of the instrument. The Post Cal. position
allows you to perform additional calibration after
measurement session and add its results to the data file.
There are three options for saving calibration results: not
to save (Off), save in the last file (Last File) or save in the
files which will be created after the last calibration
(After Cal.).
<ENT>