There are four diagram areas on this dialog. Depending of the selected mode and analyzer type, one or more diagram areas are enabled for usage.
For every visible diagram, a measurement must be made to create a valid main calibration dataset. When all the required calibration data has been created, the SAVE button gets enabled and the UPATE button receives a green background to indicate, that a complete main calibration dataset is now recorded.
The created main calibration dataset can now be used in the application by simply pressing the UPDATE button, which will also close the dialog. If one or more curves do not match the expectations simply rerun the needed calibration by pressing the button below the diagram again.
When closing the dialog using the UPDATE button, the calibration status in the status bar is updated.
To get smoother scans when the measured object s resistance is near one of the calibration references (means i.e. the measured resistance is 50Ohm real which is identical with the reference value 50Ohm) an over scan feature was added.
In the calibration dialog exists an input field , where the number of scans can be entered. This number of scans is executed when the readXXX button is pressed. The calibration curve used is the arithmetic mean of all scans executed. The higher the number, the smoother the calibration data is.
The time needed to create a i.e. 5x over scan is about 5 times the duration needed for a 1x over scan. The resulting calibration data file contains no information how many over scans where used during creation
Starting with release 2.8.5d of vna/J there are two modes for the calibration.
Depending on the analyzer type, the maximum scan range of the analyzer is divided into 1 or more ranges with different number of calibration steps. This results in enhanced resolution in these scan ranges.
This mode uses a fixed number of calibration steps in maximum scan range of the analyzer. For some analyzer types, the number of steps can be changed in the driver info dialog.
These scan ranges can be changed by the user by editing a simple text file. The driver specific text-file is created when the calibration dialog is first opened. The filename depends on the short-name of the driver. The file is located in the preset directory of vna/J. The text-file must contain lines with exactly this format:
[start-frequency]blank[stop-frequency]blank[number of steps]blank[#overscan]
If you get stuck in using these user-defined scan ranges, simply delete the corresponding file in the preset folder of vna/J