Re: NanoVNA-H4 4" LCD Display 50KHz-1.5GHz - is the right one sell on Amazon?
On Wed, 5 Aug 2020 at 17:10, CT2FZI <ct2fzi@...> wrote: It seems its located in GUANG DONG , China.
Will you pay customs taxes? I sell VNA calibration kits on Amazon, although I have sold very few on Amazon. Most sales are eBay, website or bank transfer from companies. However, I have never sold internationally on Amazon, as prices on Amazon *must include all taxes*. I can¡¯t be bothered to work out how much it is going to cost to import into different countries, so I don¡¯t bother. Dave. -- Dr. David Kirkby, Kirkby Microwave Ltd, drkirkby@... Telephone 01621-680100./ +44 1621 680100 Registered in England & Wales, company number 08914892. Registered office: Stokes Hall Lodge, Burnham Rd, Althorne, Chelmsford, Essex, CM3 6DT, United Kingdom
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Re: NanoVNA-H4 4" LCD Display 50KHz-1.5GHz - is the right one sell on Amazon?
Hello.
The final price is on Amazon, with all taxes included.
While I would buy on Alibaba probably I would have to pay separate custom taxes for product made in China.
So, my assumption is: no other taxes to pay.
For 1 year the seller have 82% positive.
I guess is a good number, still there is a risk of 18%.
What alternative do you propose for buy NanoVNA-H4 in Austria?
Thank you!
73 YO2MNE
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Re: NanoVNA firmware user interface mod
#mods
On Wed, Aug 5, 2020 at 09:50 PM, Gary Hale wrote:
Page 2 5.357 != 5.375
Page 3 Red marker is in wrong place, it is not at 7.25 MHz. SWR is 2.28
at 7.25 MHz.
Gary AG7TH
Yes, page 2 5.357 is the frequency I am allowed to transmit on, those are fixed frequencies on the band plan, and 5.375 was the closest step I could chose on the VNA... unless there is another way to match the exact frequency I am not aware of... It was either 5.25, 5.375 or 5.5 so 5.375 was closest to the radio at 5.357. And yes you are right, page 3, marker 3 was set at 7MHz and marker 4 at 7.25... I still did not see it as I see 7.25 under marker #3 but I guess it was for marker #4. I saw it in the marker list, #4 7.250... sorry about that... good eye ! (or untrained eye for me !)
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Re: NanoVNA firmware user interface mod
#mods
Page 2 5.357 != 5.375
Page 3 Red marker is in wrong place, it is not at 7.25 MHz. SWR is 2.28 at 7.25 MHz.
Gary AG7TH
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On 8/5/20 18:45, cldp@... wrote: On Wed, Aug 5, 2020 at 09:30 PM, Gary Hale wrote:
On page 2 you compare the SWR at 5.357 on the 7300 with 5.375 on the VNA.
On page 3 you compare the SWR at 7.250 on the 7300 with about 7Mhz on
the VNA.
Gary AG7TH
Hi Larry,
for 60m I know I am a little bit off because I could not get the same frequency on the VNA 201 measuring point and the frenquency you see on the 7300 is the frequency I am allowed to transmit on, so I understand what you are saying but you can see the curve is pretty close if you get to the proper frequency. My concern was more from 3.5-4MHz which is way out...
As for page 3, I don't think I understand what you are saying, yes the radio is set at 7.250 with a SWR of roughly 2.35 but if you look closely at the software, marker 3 is marked in red and is displaying 7.25 at the bottom for 2.42 SWR reading next to the red triangle... I am not sure I understand what you explain ? The frequency readings at the bottom of the chart are the reading frequency of each markers marked from 1 to 10.
Just explain me, maybe I miss understand how to read the graphics ?
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Re: NanoVNA firmware user interface mod
#mods
Hi Gary,
for 60m I know I am a little bit off because I could not get the same frequency on the VNA 201 measuring point and the frenquency you see on the 7300 is the frequency I am allowed to transmit on, so I understand what you are saying but you can see the curve is pretty close if you get to the proper frequency. My concern was more from 3.5-4MHz which is way out...
As for page 3, I don't think I understand what you are saying, yes the radio is set at 7.250 with a SWR of roughly 2.35 but if you look closely at the software, marker 3 is marked in red and is displaying 7.25 at the bottom for 2.42 SWR reading next to the red triangle... I am not sure I understand what you explain ? The frequency readings at the bottom of the chart are the reading frequency of each markers marked from 1 to 10.
Just explain me, maybe I miss understand how to read the graphics ?
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Re: NanoVNA firmware user interface mod
#mods
On Wed, Aug 5, 2020 at 08:07 PM, Larry Rothman wrote:
I was playing with the TDR on my H along with using your NanoVNA.exe 0.1.67
and they don't match.
The Nano shows the correct length of my coax at just over a meter but your app
shows close to 4X as much.
Is there an issue or did I mis-configure your app?
See the two images.
Thanks,
Larry
Larry, you should set the nanovna software to a way higher frenquency stop, the picture I see display 494m (which is a low frequency stop), if you set the stop frequency at 900MHz, you should have a maximum of around 4m which is a much more realistic measuring range for the coax lenght I see on the other picture... You should set CH0 trace to LINEAR and clear all other traces, then go to DISPLAY, MORE, TRANSFORM, turn ON LOW PASS IMPULSE and set TRANSFORM ON. Set start frequency at 50kHz and stop frequency at 900MHz, you should get the right lenght on both VNA and software. The lower the stop frequency is, the longer measure you will get. At 900MHz stop, you should see around 4m which fit the lenght of coax you currently have.
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Re: NanoVNA firmware user interface mod
#mods
On page 2 you compare the SWR at 5.357 on the 7300 with 5.375 on the VNA.
On page 3 you compare the SWR at 7.250 on the 7300 with about 7Mhz on the VNA.
Gary AG7TH
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On 8/5/20 00:28, cldp@... wrote: @OneOfEleven,
my nanovna-h v3.3 display is pretty much matching what nanovna.exe application displays (something I had a hard time to acheive with nanovna saver, reading were always higher than on the VNA). What I see on the screen of the vna with your firmware is pretty close or spot on with the nanovna app.
I decided to make a test because I did try to tune an antenna in a vehicule this past afternoon from 28-29MHz and the readings I was getting with the VNA were way out compared to the radio. My VNA was displaying SWR of 3 over and the radio displayed 1.4... I did reset/recalibrate and still same result.
So I did try to compare my VNA with my IC7300 on my home station HF antenna. Sometime reading are out but most of the time, really close or near perfect match.
Where I am having some dispecrancies between my radio SWR and my nanovna-h running your firmware mod specially in low frequency like 3-4MHz. Reading from the radio show 1.15 SWR and nanovna display 1.67. And strangely, on 28MHz my home antenna is getting the same readings on the VNA and radio (where as when I was trying on the mobile, it was way out).
What can cause this behaviour (not sure if it is related to the firmware you are working on though, this is why I ask).
See attachment for comparing both VNA and radio readings.
Thank you !
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Re: NanoVNA firmware user interface mod
#mods
On Wed, Aug 5, 2020 at 05:20 AM, OneOfEleven wrote:
Hi Alezis
Does your ICOM have an antenna tuner of any kind built in I wonder ? .. that
would change everything.
Also, when you move the antenna between the ICOM and the VNA is the way the
coax is grounded changed at all ? .. some coax/antenna arrangements can have
a big dependency on the grounding method (if any is used), but knowing nothing
of your setup I can only guess at the moment.
Is the coax acting like an antenna in anyway do you think ? .. ie not entirely
baluned/choked from the antenna.
Hi, thank you for the reply. The Icom does have an antenna tuner but of course for the test, I left it off line. What you saw in the SWR readings were without having the tuner engaged, otherwhise, there is no SWR visible on the readout when the tuner is engaged. For the grounding, I have a bus bar with all gear (radios, switches, ect) grounded to that bus bar. So when I move the coax from the radio to the VNA, the only thing not being grounded is the VNA-H itself. I proceeded to ground the VNA either on the shield of the SMA connector or on one of the VNA screws but reading does not change much, still higher in 3-4MHz on the VNA than on the radio. I have a small RG174 pigtail (from the nano vna kit) from the VNA to the antenna coaxial cable with the use of a SMA to SO-239 adapter. I did calibrate the VNA using the pigtail and the adapter. The antenna is a commercial one with a un-un from Comet Antennas, it is an end fed antenna (vertical) so yes there is a sealed un-un on the antenna. If you have other ideas why I get such differences on some frequencies, let me know... I will try again without the pigtail but I don't have the right adapters at the moment so I cannot try...
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Re: NanoVNA firmware user interface mod
#mods
I was playing with the TDR on my H along with using your NanoVNA.exe 0.1.67 and they don't match.
The Nano shows the correct length of my coax at just over a meter but your app shows close to 4X as much.
Is there an issue or did I mis-configure your app?
See the two images.
Thanks,
Larry
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Re: Dreaming a new option for nanoVNA
On 8/5/20 2:59 PM, WB2UAQ wrote: Use a fiber optic link into the cubesat. I used one a few years ago to isolate a radio for field testing. Sorry that I can't remember much about it but it was not a big deal. We had some kind of fiber optic to USB device...one a the radio and one at the lap top. See no reason why this wouldn't work for the cubesat. 73, Pete We use those at JPL for testing too.. Mostly to provide galvanic isolation. Look for "Fiber USB Extender" and you'll get plenty of choices. They're in the $100-200 range. You'll also see "USB Active Optical Cables"
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On 8/5/20 2:23 PM, CARL HUETHER wrote: A preamp is often needed on low noise receiving only antennas for 160 and 80 since they are negative gain antennas with excellent SNR and directional performance.
The Waller Flag, for instance needs about 40-45 dB gain.
Carl
On 07/12/2020 5:27 PM OneOfEleven <cmoss296@...> wrote:
Trouble is, these pre-amps have a LOT of gain once you get as low as 50MHz, mine has an attenuator on it because of that, and it's only stage of amplification in the entire receiver system, which is RF from the antenna, through the pre-amp and filtering then straight into a 16-bit ADC running at 125MHz (FPGA SDR).
I would not use a pre-amp on HF with todays radios.
The OPA656 is a nice low noise operational amplifier to make a low noise preamplifier for lower frequencies. It will be hard to beat, except with a discrete JFET design such as that from Jefferts The nice thing about the op amp is that it can have fairly decent high level signal handling. Both of these can make a MF-HF LNA with a noise that's less than the galactic background for a short antenna (which is quite bright at 5MHz, if it weren't blocked by the ionosphere)
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Re: Dreaming a new option for nanoVNA
Use a fiber optic link into the cubesat. I used one a few years ago to isolate a radio for field testing. Sorry that I can't remember much about it but it was not a big deal. We had some kind of fiber optic to USB device...one a the radio and one at the lap top. See no reason why this wouldn't work for the cubesat. 73, Pete
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A preamp is often needed on low noise receiving only antennas for 160 and 80 since they are negative gain antennas with excellent SNR and directional performance.
The Waller Flag, for instance needs about 40-45 dB gain.
Carl
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On 07/12/2020 5:27 PM OneOfEleven <cmoss296@...> wrote:
Trouble is, these pre-amps have a LOT of gain once you get as low as 50MHz, mine has an attenuator on it because of that, and it's only stage of amplification in the entire receiver system, which is RF from the antenna, through the pre-amp and filtering then straight into a 16-bit ADC running at 125MHz (FPGA SDR).
I would not use a pre-amp on HF with todays radios.
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Re: NanoVNA firmware user interface mod
#mods
Bom trabalho! :)
/
Nice job! :)
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Re: NanoVNA firmware user interface mod
#mods
OneOfEleven
Allow me to change your software icon?
Thank you !!
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I followed your plan to install nanovna-saver on an imac running high sierra 10.13.6. Installation ran with no errors but when I tried to run from terminal. got the following error (see attachment),
Will this version only run on catalina?
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Re: NanoVNA firmware user interface mod
#mods
@ OneOffEleven? Please where can I find your PC program for NanoVVNA-H4 ?
Thanks
Jos
Op 5-8-2020 om 19:03 schreef OneOfEleven:
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On Wed, Aug 5, 2020 at 01:44 PM, Igor Jobim wrote:
Is it possible to copy the information from the SD card to the computer using
nanovna.exe?
A new feature, I mean. It could do yes as my firmware has the sd_list and sd_readfile commands enabled.
I'll look at adding it into the windows exe at some point.
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Re: NanoVNA firmware user interface mod
#mods
On Wed, Aug 5, 2020 at 01:44 PM, Igor Jobim wrote: Is it possible to copy the information from the SD card to the computer using
nanovna.exe?
A new feature, I mean. It could do yes as my firmware has the sd_list and sd_readfile commands enabled. I'll look at adding it into the windows exe at some point.
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Thank you RandMental!
I am a ¡°normal user¡± and have failed to make saver function on three different machines and four operating systems. I have had lots of help but I¡¯m too ignorant to put it to good use. For instance I have finally got saver to operate on one of my 32 bit windows 7 machine. However, I can¡¯t get it to connect to my nanoVNA. Previous to the installation of saver I was able to get it to show up in device manager. Afterward, it ceased to do so. I saw an earlier post that dealt with this issue and I will pursue that later.
SUGGESTION! Could you guys start a user group for us ¡°normal users¡±? It could include nanovna-users, NanoVNA-2, and tinysa. I went two days without checking my email and found over 250 emails in my inbox. You could post links to stable saver versions and methods to deal with common problems. Please develop a version for windows 7 on a 32 bit machine. I have at least four of them. Can I ship one to someone who knows how to do it?
Also I would be willing to test some of these versions. I am obviously a ¡°normal user¡± and would be a good test. I have a 64 bit MacBook Pro with VMware fusion with Windows 7 Pro. I also have a 32 bit windows 7 pro and a desktop window 7 pro that I use regularly.
Thanks to all of you,
Joe
Joe Joncas WA7MHB
Lincoln County Radio Amateur Club
541-272-3207
joe1@...
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On Aug 5, 2020, at 2:05 AM, RandMental <randmental@...> wrote:
Dear @DiSLord, @OneOfEleven @Holger and others
I am very impressed with the progress made on both the -H and -H4 firmware and the NanoVNA-Saver and the work you are doing.
However, I want to raise a concern as I see this project go the way of many other open-source community projects where the energy and initiative starts running low before the project and development has been stabilised for general use. The last few weeks have especially been chaotic for the normal users, with various releases trying to maximise performance.
I thus want to urge that we pause chasing new features and higher performance, and work together to release and test stable versions of the firmware and PC programs. If we don't we risk losing the support of the many users that have no interest in development and maximum performance, but just want a stable, usable NanoVNA for their RF and antenna projects work.
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Re: Dreaming a new option for nanoVNA
On 8/4/20 3:25 AM, Piero Tognolatti wrote: Hi,
is anyone able to implement a new feature in the nanoVNA menu?? I need to locate the nanoVNA inside a mokup of a cubesat to take S11 measurement for a while (10 minutes, for example). I cannot use have any cable running out from the satellite (to not disturb measurement), so I would like to set the nanoVNA in order to take and store measurements, for example a measurement every minute. Have you got room for a RPi or Beaglebone? Use the USB interface and NanoVNA-Saver? Can you tolerate WiFi? you can use VNC to remotely operate it.
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Dr. David Kirkby, Kirkby Microwave Ltd
Morariu Horia Iancu
CT2FZI
Igor - PY3IG
