Is there a software application for the 8714ES to calculate K factor?
No, there is not a software application to calculate K factor for the 8714ES.
Google could be your friend. I did a search on "stability factor touchstone file", and see
How to calculate stability using Touchstone file?
I'm sure you will find plenty of others. So just read out the S-parameters, save as a Touchstone file, and you are done.
You could ask John Miles if there's any chance of him adding it to his vna.exe program
KE5FX GPIB Toolkit
I expect that can read from an 8714ES.
Of course, there are other approaches, like read into programs like ADS, but that's rather a sledgehammer to crack a walnut.
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