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Won't work - the Nano is a USB CLIENT.
You need to have a USB HOST port in order to plug in a memory stick.
This has been discussed before in the forum.

A quick check on Amazon shows a simple USB female-to-female connector (set of two, actually) costs about $6. One of those and the existing cable that comes with the NanoVNA gets you “on the air” (assuming you have a USB memory stick, which they seem to be handing out in cereal boxes these days ?).

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Regards,
Robb N2VJO

Great idea Robb

... or alternatively, make the internally installed SD card readable via the USB interface. No case modification would be required.

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73

Gary, N3GO

How about an off-the-wall suggestion from a newbie?

How hard would it be to use a USB memory stick on the already existing USB port? If that is feasible, then all users need do is buy an appropriate USB-female to USB-C cable..

Just thinking out loud...
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Regards,
Robb N2VJO

Is there anywhere in the UK I can get an authentic version please?

Hi to all.
I had problems getting an SAA-2N using vna-saver running on windows 10, specifically it would not connect to the USB port. I solved that, and having used the vna saver on my new laptop I decided to use it in the workshop on my old Win-7 machine.

The problem is the nanovna-saver exe wont run past flashing up a dos window with what I presume is the ini files and an error message. This screen stays visible for less then a second and I came up with the idea of videoing the screen at run time to capture the image which I enclose.

Can anyone advise what program or module is missing that prevent the nanovna saver running?
My win version is 7 pro with SP1, and C++ loaded. The vna is V2_2 build time October 2020
cheers
joe

Yes, that is correct.

On Wed, Dec 8, 2021, 6:41 AM Steven Bailey via groups.io <sbailey64=
[email protected]> wrote:

Sorry Donald...somehow I conflated Donald into Doug.

Sorry Donald...somehow I conflated Donald into Doug.

Hi Doug,

So the null gain (in -DB) will not be accurate but the frequency of the null will be accurate...if I do no calibration?

Thanks,

Steve

Steven: Taking this further, if you are just looking for a return loss null, such as for tuning a magnetic loop to a given frequency, you don't even need to do any calibration, as the frequency will be accurate even if the measurement is not.
73, Don N2VGU

Thanks everyone for the great advise. I especially like the screen shots (and experiments) Roger made (thanks Roger). For my purposes (looking at antenna reflections), re-calibrating looks to not be necessary.

Steven,

For best accuracy you need to re-calibrate. This is especially true if you only have 101 data points since there will be more interpolation when you zoom.

However if you are only interested in SWR or RL the interpolation feature (on H/H4 hardware and some other models) works very well. Here is a link to some actual measurements where I "zoomed in" on a 20 m dipole.

/g/nanovna-users/topic/73210908#12926

Roger

Steven,
the 6MHZ and its surroundings from the first production may be even more interesting when the value of the cooling condenser was inadequate.
Read more on my web site.

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Gyula HA3HZ ()

On 12/7/21 7:12 AM, Steven Bailey via groups.io wrote:

Hi all...am new to this group. Have a question about calibrating the NanoVNA. If I say calibrate from 3-30 Mhz...and then decide to look (or zoom in) at frequencies from say 5-6 Mhz...do I need to do another calibration from 5-6 Mhz?

For the standard nanovna, there's 101 points - so if you calibrate from 3-30 MHz, you have a cal point every 270 kHz.? When you zoom in, the software interpolates between those points. So over your 5-6 MHz, it will interpolate over the 7-8 points covering the range.? For the most part, it's unlikely that your VNA and connectors/cables (whatever you calibrated with) vary wildly in that range, so the results will be reasonably good.? The sort of guideline is that you don't want the *phase* of the uncalibrated reflection coefficient making a big fraction of a circle between points.

If you want better performance (or you're seeing something wonky) then recalibrating over the 5-6 MHz range gives you a calibration point every 10 kHz.

Realistically, this only makes a difference if you've got something unusual inside the calibration plane. I have been fooling with hooking up two VNAs back to back (to make all 4 measurements at once), so I have a "stub" inside the calibration plane. I'm working at low frequencies (<100 MHz), so the stub is really short.

In another experiment, I'm doing measurements with the "cal kit" connected by relays at the end of 100 ft of coax (two antennas in a phased array).? That's long enough that at higher frequencies, I get more than one wavelength in the coax, and that could make the simple linear interpolation with widely spaced points not work right.

You wouldn't have to, but the number of points it is calibrated for would
be less in the smaller range. It's best to re-calibrate and get the
benefits of all the calibration points in the new range.

Zack W9SZ

On Tue, Dec 7, 2021 at 9:14 AM Steven Bailey via groups.io <sbailey64=
[email protected]> wrote:

Hi all...am new to this group. Have a question about calibrating the
NanoVNA. If I say calibrate from 3-30 Mhz...and then decide to look (or
zoom in) at frequencies from say 5-6 Mhz...do I need to do another
calibration from 5-6 Mhz?

Hi all...am new to this group. Have a question about calibrating the NanoVNA. If I say calibrate from 3-30 Mhz...and then decide to look (or zoom in) at frequencies from say 5-6 Mhz...do I need to do another calibration from 5-6 Mhz?

Indeed it was and it seems to be giving me good measurements now with the antenna I am testing. With an antenna tuner I can get an impedance of 32 ohms at 1620 KHz which is my desired frequency. On another note, I talked with a friend of mine who is a retired RCA employee with a distinguished past and he was impressed that a piece of test equipment like this can be had for about $100 and I am impressed too. If operated with its limitations in mind this is a fantastic device especially after I flashed one of the better firmwares available in the files section.

Yes! That's the kind of thing I was trying to get you to find. That type
of mechanical issue is almost always the problem when something that was
working suddenly stops, especially after manipulating the setup, even in
innocuous ways. It's often in the least expected place.

I found the center conductor and dielectric and after putting them back in the VNA is responding correctly through out its full range. Sometimes a little poking around can solve a huge problem.

On 12/6/21 7:01 PM, Nicholas wrote:

A little embarrassing but I think I found the problem. I checked the SO-238 to BNC male adapter I was using and THE CENTER CONDUCTOR IS MISSING! It likely got lost on a piece of coax that I was using at one point. I am going to find it and put it back in. That would certainly result in an open no matter what antenna I use!

A classic problem is when someone "stretches" a piece of coax to make it reach (or when pulling through a conduit or around something else), and the center conductor pulls back within the shield, taking the center pin with it.