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SVANTEK 977W User Manual
Calibration By Measurement
Calibration by measurement for the sound measurements can be done in the
following way:
1. Select
the
calibration
by
measurement
(highlight
the
Calibr. by Measurement
text) from the
Calibration
sub-list and press the
<ENTER>
push-button.
2. Attach the acoustic calibrator SV 30A
(or equivalent
114 dB / 1000 Hz
)
carefully over the microphone of the instrument.
Note: It is also possible to use an electro-mechanical pistonphone, which generates a signal (ca
124
dB) or different type of acoustic calibrator dedicated for ½” microphones. In any case, before
starting the calibration measurement, the user has to set the level of the signal generated by the given
calibrator (Cal. Level position of Calibr. by Measurement sub-list), which is stated in the calibration
certificate of the unit (the value of the Cal. Level set by the manufacturer of SVAN 977W is equal to
114 dB). It is also necessary to switch the instrument Range to the High level setting.
3. Switch on the calibrator and wait approximately 30 seconds for the tone to
stabilise before starting the calibration measurement.
4. Start the calibration measurement by pressing the
<Start/Stop>
push-
button.
5. Stop the calibration measurement by pressing the
<Start/Stop>
push-
button after stabilisation of the calibration measurement result.
The calibration delay time is set to
3 seconds Waiting for the start of the
measurement the
Delay
is counted down
on the display. After the end of the
measurement, the result is displayed in the
bottom line. The measurement is running
until the user presses the
<Start/Stop>
push-button.
….
It is recommended to repeat the calibration measurement a few times to ensure the integrity of the calibration.
The obtained results should be almost identical (with ±0.1 dB difference). Some possible reasons for unstable
results are as follows:
the calibrator is not properly attached to the instrument,
there are external acoustic disturbances such as high noise levels close by,
the calibrator or the measurement channel (the microphone, the preamplifier or the instrument itself)
are damaged.
Note: During the calibration measurement, any external disturbances (acoustic noise or vibrations)
should not exceed a value of 100 dB (when using a calibrator that generates a level of 114 dB).
6. Press the
<ENTER>
push-button to
accept the calibration measurement
result.
The calibration factor is calculated, stored
and displayed (cf. next Figure) after
pressing the
<ENTER>
push-button and
confirmation (
Are you sure? Yes
).
<ENT>
Note: The user should press the <ESC> push-button to quit the calibration procedure without saving
the calibration factor.