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A real mess of the coefficients of the 85032F (current 9 GHz N kit)

Question asked by drkirkby on Jan 11, 2015
Latest reply on Jan 19, 2015 by bhokkan
Someone I know wanted to get the coefficients of the 85033F 9 GHz N kit to use with another make of VNA. He was quite confused about them, and concluded there were various revisions of the kit.  After having a look, at 

http://na.support.keysight.com/pna/caldefs/stddefs.html

I can understand his confusion. The HTML files linked from there on the 85033F have all sorts of inaccurate data in them. 

As far as I can work out, looking at my PNA, the coefficients are: 

**Open**
C0=89.939
C1=2536.8
C2=-264.99
C3=13.4
offset delay = 41.19 ps
Offset loss = 930 M Ohms/s (a really nice and obvious unit !!)
Offset Zo = 50 Ohms
Min frequency=0 MHz
Max frequency=999 GHz (a bit outside the range of the 20 GHz VNA)
Coax or waveguide = Coax

**Short** 
L0=3.3988
L1=-496.4808
L2=34.8414
L3=-0.7847
Offset Zo = 49.99 Ohms 
Offset delay = 45.955 ps

That data is consistent with my 8753ES and 8720D.  But the files linked at 

http://na.support.keysight.com/pna/caldefs/stddefs.html

for the 85032F show a pretty random mix of values, depending on what instrument you look for. For example

* For the PNA, the male and female coefficients are completely different. But they are not in my PNA's firmware. 
* For the 8753D, a sliding load with a lower frequency limit of of 4 GHz is indicated. But the 85033F has no sliding load. 
* For the 8753D, the offset delay of two opens are different, despite the C0, C1, C2 and C3 are all the same. 
* N9912A - the offset delays are rounded to one decimal place. Sine that is actually the XML file used, rather than a binary download, I assume the values are not really optimal, although having played with an N9912A, perhaps it doesn't matter too much, as that instrument will not win any prizes for accuracy. 

Anyway, it seems to me that quite a lot of the data on the 85032F needs looking at. 

Dave

Edited by: drkirkby on Jan 12, 2015 1:12 PM  

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