开云体育

No intention to complain just trying to make a reasonable effort to get the original Hugen unit as for basically the same price his design and build quality is obviously better, and also rightfully deserves the credit and the sale over the others. I would assume some ebay resellers are offering the original they get wholesale at AliBB, but its hard to differentiate them and I don't think the 900MHz stated frequency limit automatically disqualifies a particular unit from being original, specially if it seems to have the correct look and packaging, but then again it also does not guarantee anything either. I wish sellers would publish a picture showing the PCB and shields as it would make selection easier, and even if they ship something different then at least one could file a not as described complaint, although it would hardly be worth the hassle trying to return the unit.

Herb,

Actually, two different odd harmonics get used.
From Erik's post of /g/nanovna-users/message/1743

You are explaining well, except the SW uses above 300MHz the 3rd harmonic of one clock and the 5th harmonic
of the other clock to avoid detecting the 3rd harmonic of the mixing product of the 1st harmonics of the clock's
Example 200MHz + 200.00166MHz produce from 1st harmonic 1.66kHz which will include a certain amount of 3rd harmonic at 5kHz.
Using 200MHz + 120.001MHz produces only 5kHz when their 3rd and 5th harmonic combine

Also, the Si5351 is spec'd to operate at up to 225 mhz, anything beyond that is a gift.
Those for which the PLL craps out at 290 mhz are not necessarily from "shady sources".
Perhaps just cut from the outside edge of the wafer, but still perfectly compliant with the spec.

Jerry, KE7ER


On Fri, Jan 17, 2020 at 09:20 AM, hwalker wrote:

On Fri, Jan 17, 2020 at 07:49 AM, <nanovnagroup@...> wrote:

From the link at the Wiki section:


It states that top frequency range is 900MHz:
========================================================
It actually states that third harmonic operation is 300-900MHz. The fifth
harmonic is used for 900-1500 MHz operation. This is a basic principal of
operation for the NanoVNA that should be well understood by most user's. I
would think that would be especially true if the user's the name is
"nanovnagroup" :)

As Larry replied, some NanoVNAs will only able to reliably achieve 266.7-800
MHz third harmonic operation, and 800 - 1.300 MHz fifth harmonic operation.
Hugen specs his v3.4 NanoVNA-H as operating reliably to 1.5 GHZ. His v3.4
board uses the same synthesizer chip as his original NanoVNA-H so I'm guessing
he must be cherry picking his synthesizer chips. Think of it as overclocking
your PC's clock, the majority of legitimate chips will operate reliably pass
their marked frequency, but those using seconds from shady sources probably
will not.

- Herb

On Fri, Jan 17, 2020 at 06:30 AM, Ken Kayser wrote:

Hi. Has the Save/Reteive Settings feature ever been implemented? Seems like I have seen a post that said it was but can't find it in the program. Thanks all.
=================================================

Ken,
The NanoVNA does not allow the settings you save in memory locations 0-4 to be saved externally and restored to the unit. Rune's NanoVNA-saver program allows you the save and retrieve calibration settings that you perform within his program; however, these are only for use within his program.

If you are asking if NanoVNA-saver allows you save and restore configuration information, such as its current operating state, that is not a feature Rune has implemented but is probably on his to do list.

- Herb

On Fri, Jan 17, 2020 at 07:49 AM, <nanovnagroup@...> wrote:

From the link at the Wiki section:


It states that top frequency range is 900MHz:
========================================================
It actually states that third harmonic operation is 300-900MHz. The fifth harmonic is used for 900-1500 MHz operation. This is a basic principal of operation for the NanoVNA that should be well understood by most user's. I would think that would be especially true if the user's the name is "nanovnagroup" :)

As Larry replied, some NanoVNAs will only able to reliably achieve 266.7-800 MHz third harmonic operation, and 800 - 1.300 MHz fifth harmonic operation. Hugen specs his v3.4 NanoVNA-H as operating reliably to 1.5 GHZ. His v3.4 board uses the same synthesizer chip as his original NanoVNA-H so I'm guessing he must be cherry picking his synthesizer chips. Think of it as overclocking your PC's clock, the majority of legitimate chips will operate reliably pass their marked frequency, but those using seconds from shady sources probably will not.

- Herb

Unless you purchase from hugen's preferred seller, you don't really know what you're going to get.
I purchased a Gekko unit back in June - and there was nothing wrong with using it over 1GHz.
Others have had issues.
If people want to complain about what this unit does for $39US, then they should buy one of the $400 units sold on ebay and elsewhere with reliable specs.
A number of forum members have 2 or even 3 of the Nano's and I for one have already modified mine to reduce noise and increase the freq range specs.
my $0.02

That's by design.

A cheaper solution would be to take a board mount female SMA connector,
solder a strip of 3 header pin sockets to it instead of a PC board.
Then clip up a pin header strip into sections of 3 pins to mate with the sockets,
and add a selection of junkbox resistors and coils and caps and crystals to each.

Total cost of about $5. No U-FL connectors to break. No $40 demo board.
If you keep everything down under 100mhz, no need for 10ghz connectors.
The only thing that's going to wear out is the 3 header pin sockets,
which are easy to replace for pennies.

Jerry, KE7ER

I wonder if any H versions with the right original look and still being advertised ebay now a days with only a 900MHz top frequency limit instead of 1500MHz are automatically guaranteed to be "cheap Chinese" Hugen clones, or might as well just be older leftover stock of earlier genuine builds before the higher 1.5GHz was achieved. Asking because the former was recently suggested here:

/g/nanovna-users/message/9752

Just trying to gather as much info as possible before ordering a unit, but for my own reasons I am not too motivated about ordering at his AliBB store, so please no need to comment on this.

I thought the rocker switch was meant only to move the marker(s) position.
But if I use it just after having changed the Start or the Stop frequencies of the Stimulus, it acts on them... not what I was expecting.

Is that normal, as designed, or is it a bug ?
Firmware 0.5.4, compiled on December 9.

TNX

Alberto

Hugen's redesign of the original nanoVNA used harmonics to provide a stated response up to 900MHz.

Since the original design, additional testing has proved that depending on who manufactured the device and when, it was capable of 1500MHz and most firmware now allows the user to enter that as a top frequency. The caveat is that the clock chip fundamental is only spec'ed for 260MHz max and pushing it to 300MHz might not work.

Look at QRP's firmware - he has a built-in power-on test that checks the clock to see if it's stable at 300MHz and hugen created a firmware update that tops out the clock at 266MHz to guarantee 50KHz to 800MHz on all devices (as some users had issues with the 900MHz max freq).


However, the DEFAULT frequency range is still up to 900MHz - that is why when you install even the latest firmware (other than hugen's 800 version), it boots up at 50KHz to 900MHz.

You see them advertised as 900MHz devices because almost all Chinese vendors copy each others advertising info written in English and don't change much.


There have been many improvements since then including layout improvements to the circuit board that allows fairly good results up to about 1.3GHz.

All this info is contained in the almost 10,000 forum posts (!) should you want to try browsing the various topic threads.

Clear as mud?

From the link at the Wiki section:


It states that top frequency range is 900MHz:

--------------------------------------------------------------------------------------------------------
nanoVNA-H commercialized by Hugen reduced cost and enhanced usability

working LiPo
refined touch screen
better PCB layout, RF shielding
third harmonic operation 300-900MHz
Touchstone file export
standalone PC software
--------------------------------------------------------------------------------------------------------

According to this it seems the 1.5GHz top frequency for the H version was not implemented since the beginning, but was rather a later improvement? If so I would assume there might still be earlier legitimate H units out there being advertised as 900MHz top frequency, specially by non tech savvy sellers. Or am I wrong?

Hi
Seems to work ok and not crash when on continuous sweep.
Thanks Rune

I agree, they're very difficult to connect and disconnect. Here's an outlandish idea I considered...Amazon has U.FL to panel female SMA connector jumpers in lengths up to 12 inches. IF someone REALLY wanted to have a permanent fixture you could get one for each demo section and build yourself a complete demo box; that way you'd only have to connect them up once and could then tap into whichever of them you wanted to. Guess you'd have to characterize the jumpers as well...but I digress. Yep, it sounds ridiculous I agree and did I say expensive? They're around $12 for four jumpers...you do the math since you could buy a couple more nanoVNAs for the money you'd invest in such a project...but it would work. 73 - Dino KL0S

Hi. Has the Save/Reteive Settings feature ever been implemented? Seems like I have seen a post that said it was but can't find it in the program. Thanks all.

Ken

On Fri, Jan 17, 2020 at 08:07 AM, Rune Broberg wrote:

So 3.7 it is, though it might work with 3.6 - I
just don't test it with that. :-)

Does not work with python3.6 here.

nick@LM19-3:~/nanovna-saver-0.2.2$ python3.6 ./nanovna-saver.py
Traceback (most recent call last):
File "./nanovna-saver.py", line 17, in <module>
from NanoVNASaver.__main__ import main
File "/home/nick/nanovna-saver-0.2.2/NanoVNASaver/__main__.py", line 21, in <module>
from PyQt5 import QtWidgets, QtCore
ImportError: cannot import name 'QtWidgets'

All good with python3.7 of course.

On Thu, Jan 16, 2020 at 04:05 PM, Pierre Martel wrote:

Anyone can report what version and linux distro they are using where
NanoVNA-saver works right away?

Pierre

The instructions at used to work perfectly on Linux Mint 19 before PyQt5 got changed back in December.

What distro are you using?

If it is Debian based please try the suggested edit to ~/nanovna-saver/requirements.txt See post #9737.

Nick

On Thu, Jan 16, 2020 at 10:39 PM, Denis Collins wrote:

den@den-ThinkPad-T520 ~/nanovna-saver $ pip3 -V
pip 19.3.1 from /usr/local/lib/python3.6/dist-packages/pip (python 3.6)

Interesting. That's a much newer version of pip3 than you get from the python3-pip in the LM repos.

How did you install pip3 19.3.1?

Please can you do

$ which pip3

and post the result?

Did you get the PyQt5 error when you tried to install PyQt5==5.14.1 with your version of pip3?

Glad the requirements.txt hack worked for you.

Nick

I also suggest getting the Kindle book by Christoph Schw?rzler. It's very useful.

--
Trystan

Hi all,
I have uploaded a *potential* fix for the 0.2.2 crashes seen when running
continuous sweeps following an in-application calibration. It's available
on GitHub as a .exe:



(Look for 0.2.2-1)

If you are experiencing this problem on Linux or Mac, you can pull from the
Development branch on GitHub for now - if this is confirmed to fix the
problem for users other than me, I will make a proper 0.2.3 release soon :-)

--
Rune / 5Q5R