Having trouble overlaying data on Smith Chart using LabVIEW

[alexndr]

I am receiving data from an HP8720A Network Analyzer and want to display it on a Smith Chart.  I have developed my VI with the Smith Multi Point.VI as a sub VI.  When I run my VI the subVI displays the data but it is not overlayed properly on the Smith diagram.  I am normalizing my data and it looks exactly as the analyzer but the data is not directly over the Smith diagram, how can this be corrected?

[JohnnyH]

Hello alexndr,

I'm not entirely sure why your graph is not in the right position, but I was looking at one of the examples for the Smith Multi Point.vi, and I think it provides a good idea of how this data can be manipulated.  If you look at the detailed help for this VI, there is an example at the bottom called Smith Plot With Zooming.vi.  If you go to the block diagram, there is a VI in the lower right of the outer while loop called Remap Smith Plot Section.vi, which demonstrates how the Smith Plot can be manipulated.  Hopefully this is helpful!

[Chazzzmd]

Alexndr,

Did you ever figure out why your data was not overlaying properly over the smith chart? I have been messing with the same exact issue on the Agilent N5230A I have. The plot is coming out just right, but not overlaying correctly. I have referenced the Smith Multi point.vi with no success. It's starting to become very frustrating, and I just want to get this script up and running.

Basically I have r & i being converted to a complex, then being normalized (50.00), and finally going into the input of the smith.vi.

Argh!!

Any way any help would be much appreciated.

Thanks,

-Chazzzmd