User Calibration And Preparations; Overview; Calibration Modes - Deepace KC901V Manual

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Chapter 3 User Calibration

and Preparation before Measurement

KC901V has been calibrated on its ports at factory so that the field calibration

can be skipped. Due to various reasons, the factory calibration can't correct error in

field-use perfectly, so the curves will have some imperfect drifts. But in normal engi-

neering applications, as long as the testing result can help with analyzing and judging,

there is not necessary to spend time on user calibration.

During measurement, cables and adapters are normally used. They will intro-

duce loss and phase shift. With temperature drift and aging, instrument's perfor-

mance will degrade. If this has big influence on your measurement and makes test

result no longer usable, a user calibration should be performed.

Calibration data is only valid if measuring DUT with the same conditions (cables,

adaptors, temperature, analyzing bandwidth and sweeping speed etc.) as performing

the calibration. If these condition has changed, there will be new errors. Calibration

conditions should be as close as it can be the actual situation of the test.

Try to reduce the times of changing different adaptors during testing. It's not

recommended to put an extra adaptor on just for protection the ports.

There are three kinds of calibrations in KC901V, factory calibration, system cali-

bration and user calibration.

Factory calibration: Instrument has a high-density full-band calibration. using

scaling algorithm to do the interpolation reaching higher density. The factory calibra-

tion is saved into the instrument permanently; users can't reset it or use it directly.

But it can override the system calibration by restoring factory settings.

System calibration: after the instrument comes out from the factory, the data of

system calibration is the same as factory calibration. System calibration can be used

directly. It also can be done by users. After doing the system calibration, every fre-

quency of the instrument is calibrated, the basic error corrections can be maintained.

So it's not necessary to do this calibration again in most situations. When restoring

the factory settings, the system calibration which is set by user will be abandoned and

the system calibration data will be the same as the factory calibration.

User calibration: it can be set by user anytime. This calibration will do the cor-

rection to every data point according to the actual setting. There won't be interpola-

tion errors. Therefore, its accuracy is higher than factory calibration as well as system

calibration. User calibration is only applicable for the set frequency. If the setting pa-

rameters are changed, the calibration data will be useless but still saved temporarily.

If we go back to the last setting parameters, the calibration data is still effective.

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