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Thanks DiSlord for explanation, I understand. Op di 5 okt. 2021 om 20:13 schreef DiSlord <dislordlive@...>:

Difficult implement fast vector interpolation on this CPU: NanoVNA measure real imag, for convert it to Z angle need: Z = sqrtf(real*real + imag * imag) angle = atan(real, imag); // here more

Hello DiSlord, Should the interpolation not be based on radial interpolation: so average of modulus and average of angle? All things here are complex numbers, so I think that we should also do a

Better do one calibration or on NanoVNA or on CPU side Calibration data contain noise, this noise added to calibrated value (increase noise), after send to CPU and use as basic calibration in CPU

I was referring to interpolation between points. If you calibrate with 401 points between 1 and 1.5G on the device and then calibrate with 2000 points on PC, all those in between values are

That's useful.

Well, as a substitute for "no calibration" which isn't easy to command, if the wideband cal is stored in #0, it has the advantage of "power cycle and you're in a known state" I'm not sure what the

Challenging but doable, you will have to use "Shunt through" method. For an easy to understand explanation of the problem: https://www.youtube.com/watch?v=1UbEz73FGCU

in my firmware need use: 'scan start stop points mask' mask - output mask #define SCAN_MASK_OUT_FREQ (1<<0) // Output freq in Hz #define SCAN_MASK_OUT_DATA0 (1<<1) // Output complex S11 #define

If I understand correctly this will lead to interpolation by Nano firmware which is not a good idea.

What commands make the NanoVNA send uncalibrated data?? I was casually looking around, and it seemed to me that you can turn off calibration with the menu, but there's no command that you can send

It's all about how accurately can you measure the reflection coefficient: Gamma = (Zload-Z0)/(Zload+Z0) For Z0 = 50, and Zload = 1 gamma = -49/51 = -0.96078 A 10% change in Zload would be gamma =

That is a good idea. I just started using NanoVNA-saver because it's in Python, and I'm familiar with scikit-rf.

This is a tricky measurement even with a high grade VNA. A compact article on the topic is at:

Thanks Roger, Op di 5 okt. 2021 om 03:07 schreef Roger Need via groups.io <sailtamarack= [email protected]>: That is indeed good advice. This slot 0 will remove the 'large errors/compensation' of the

NanoVNA firmware can send uncalibrated data, then calibration need use in external software But by default NanoVNA send calibrated data (if calibration apply on NanoVNA) in this case not need made

I need to measure a very low impedance device for a non-ham application.....probably less than 1 Ohm.? Is the NanoVNA able to make an accurate measurement on such a load in the 14 MHz range? 73,

Rune had a good suggestion where you calibrate slot 0 in the NanoVNA for the maximum frequency range you would ever need and then leave it that way and use the other slots for other frequency ranges

I'm not sure about the accuracy implications - there are some numerical precision effects that would need to be looked at. I believe there is a "scanraw" command in some of the firmware versions that

Well, saver and the device are two completely separate entities, with some versioning differences to boot (e.g. NanoVNA-Saver works with lots of different devices). But yes, some summarizing and