negative VSWR

Cecile Bachmann

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Jul 30, 2020, 5:42:10 AM7/30/20

to VNA Tools

Hi,

recently VNA Tools II is quite often calculating a negative VSWR on my measurements. As far as I know this does not make much sense. Do you have any idea what could be the reason for this?

I have been trying to add a file for example or to send it per email, unfortunately it is too big to be added and compressing it does not seem to help.

Thanks and regards

Cecile

Cecile Bachmann

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Jul 30, 2020, 10:50:49 AM7/30/20

to VNA Tools

Hi,

I found the problem, apparently in this case one of the calibration standards was measured wrongly (the short at Port 2). When I repeated the calibration the problem was solved.

Would it maybe make sense, to add an error message for this kind of error? As a negative VSWR is quite obviously wrong.

Thanks and regards

Cecile

Michael Wollensack METAS

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Aug 3, 2020, 4:35:53 AM8/3/20

to VNA Tools

Hi,

you get a negative VSWR when the absolute value of your reflection is larger than 1.