Rion DA-21, Инструкция по эксплуатации

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97
Recording
Recording a calibration signal
Calibration for recorded data is normally performed by recording the sensor
calibration signal before or after the data recording procedure and by cor-
relating the result to the recorded data.
This method allows correct calibration even if the effect of the confi guration
elements of the sensor (extension cable, preamplifi er, etc.) is unknown.
In principle, it will be necessary to record the calibration signal again when
the confi guration elements have been changed. Input range information of
measuring device will also be required (if range switching is possible).
In the representative examples listed below, recording the calibration signal
may be necessary. In actual use, the operator should decide whether calibra-
tion is necessary, based on information given in this manual and other data.
1. Input range setting of the measuring instrument (not DA-21) was
changed.
The instrument may change output signal being supplied to DA-21
when input range setting is changed even at the same input signal.
2. Extension cable was changed (length, cable gauge, etc.)
A change in electrical impedance may result in a different output
signal being supplied to the DA-21.