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Hi David
I think you should read my response to this question.
You negative conclusion is not valid.
Pragmatic solution are still useable and in addition using the NanoVNA-saver you got it all to perfection. You even was the person who motivated Rune to developed his calibration function with L and C coefficients and his load are even able to cope with the inductive loads such as the BNC calibration kit from SDR Kits. IT IS PLAIN PERFECT David.
I know you want to flood the firmware with all sort of default professional calibration kit data, It is you who are dreaming of a tolls only very few would benefit from (who want to fool around in outdoor environment with the professional calibration kit anyway) and as a bench tool I definitely prefer the NanoVNA to be as is, as a bloody good and accurate "vector measurement engine" and solve rest of the challenges by software.
And for a spot measurement device in the field, you can do with the described tricks very well even with other homemade calibration kits having same plane for short open and load and a known delay to the real calibration plane. The only improvement I can think off is the possibility to enter negative delay in the display/Scale/Electrical delay so we also can move the calibration plane forward.
Kind regards
Kurt


-----Oprindelig meddelelse-----
Fra: [email protected] <[email protected]> P? vegne af Dr. David Kirkby from Kirkby Microwave Ltd
Sendt: 11. oktober 2019 01:14
Til: [email protected]
Emne: Re: [nanovna-users] reference plane

On Thu, 10 Oct 2019 at 23:57, johncharlesgord via Groups.Io <johngord= [email protected]> wrote:

Ken,
As delivered, the NanoVNA default calibration, Location 0, is
apparently set up with the S11 reference plane at the on-board
connector. You can run another calibration at the end of your cable
put that in another storage location if you like.
--John Gord

But it is currently *totally impossible to get a valid calibration on a cable with a male SMA on the end. *The firmware doesn’t permit one to enter any characteristics of the female calibration standards. Female SMA calibration standards will be nothing like text-book opens and shorts, whereas male calibration standards will be fairly close to text-book opens and shorts.

Without fixes to the firmware, this problem will not go away.

Dave.

On Thu, Oct 10, 2019 at 03:07 PM, Ken Bozarth wrote:

Am I missing something big here? Does this nanovna calibrate the end
of

the

cable as the reference plane? All VNAs should do this. Mine does not.
Recalling cal 0, with the TX connector open, it looks like an open.
If I

do a

complete calibration at the end of the cable, then leave it open at
the

end,

it is not an open, at any frequency. What am I doing wrong?

--

Dr. David Kirkby,
Kirkby Microwave Ltd,
drkirkby@...

Telephone 01621-680100./ +44 1621 680100

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Registered office:
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