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Pondering a simple question relating to SMA calibration devices as in those that are generally supplied with a?newly purchased Nano VNA as an example. Open is Open, that is obvious. The connector

I got my cal kit from Dr. David Kirkby kirkbymicrowave.co.uk. It includes not only extensive characterization data but also optionally verification standards which will allow you to check the quality

That is NOT a calibration board. That is a DEMO board. Those are good enough to show a VNA newbie: What would a parallel resonant circuit look like on a VNA? What would a series resonant circuit look

Sure - the original question was about possible other VNAs with better performance. I cited the Keysight FieldFox (an "inexpensive" analyzer in Keysight land :) ) as I interested in showing how they

OOOOoops,........That's W?LEV, not WLEV. For some reason I have to wait a few seconds to release the "ALT" button for the "zero" in ASCCI code to register. Who knows.......it's a digital

Jim, the NANOVNAs I contend are highly useful for us amateurs and "top level" professional applications and CERTAINLY for education. However, I use mine where I can not carry the (100-lb.) 8753C with

Yet another reason to become familiar with the complex representation of the impedance! Oh,.....yes,......AND the Smith Chart. Dave - W?LEV wrote:

I agree that the simple formula is of little use in real world use and it cause more confusion than it is worth. Also.... SWR = Zt/Zo for Zt >= Zo and Xt and Xo both = 0 Example: Zt = 100 + j0 and Z0

This constant SWR circle is certainly a useful exposition of the concept and is very nicely done. Having the Smith Chart display on the nanoVNA can be very helpful even if you retrieve data

As noted elsewhere, the basic measurement uncertainty is around 1%, so if your cal standard uncertainty is 1%, then you're in the right ballpark. But it *really* depends on what you're measuring.

One other thing.. The "raw measurement" that the NanoVNA makes is essentially a filtered sum of 48 samples. The raw adc samples are probably about 1 part in 10^4 (call it 1E-4 fractional uncertainty)

What do you guys make of these calibration boards? https://deepace.net/wp-content/uploads/2020/10/正面-scaled.jpg Accurate enough to give a result with <3% differences?

The problem is you're in the "observer with two watches, which one is correct" scenario. Unless you have access to a (much) better measurement tool, you won't know if it's the cal standards or

W0LEV - Thats good to hear... I have heard that its not worth upgrading as the nanoVNAs are good enough... I guess this is looking more like finding a better calibration kit to use with the N.V

Siegfried Jackstien - Thanks for the recommendation, I will research these. John Gord - Re maintaining a consistent length between O, S, L - the three now provided with the nanoVNA are just RPSMA

Don't downplay the accuracy of the NANOVNAs. I have compared several offerings from the NANOVNAs with the HP 8753C with the associated S-Parameter test set using HP cal. standards. The agreement,

Arie, Thank you for posting your paper. I suggest that you correct the text below to state that this formula is only true when the reactance X is 0. I have seen on many occasions people thinking that

Thanks for the correction. I put these together quickly and should have proofread them for errors. Here are the corrected versions showing several complex impedance values that all result in an SWR of

Hi Russ, Lets put it simple without too many formulas. There has been a lot of math to come to the SWR formulas but we can think about it. The reflection coefficient is the percentage of reflected

You can certainly make a homemade short or open, but characterizing it accurately is another thing entirely. Without accurate characterization a standard is useless. 73, Don N2VGU