Re: NanoVNA vs. MFJ-259B Antenna Analyzer
Thanks for sharing this - I just joined this group today!
I had heard several times how the NanoVNA wasn't that accurate, so I was surprised to see how it compared to the MFJ analyzer. Thanks for sharing my video!
Hopefully I can learn more about this amazing kit on this forum
--
Carson VA3OSO
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Re: Definition of resonance
Yes, this has been a good learning exercise. Remember that I made the test-setup to intentionally get some weird results to see if those could be handled by an antenna tuner and describe how. And yes, I did not use a current choke, intentionally, normally I always do. I am impressed that Roger could guess my setup and make a duplicate. I am always telling my colleagues to use a current choke (CMC-filter) to avoid the coax screen to be a part of the antenna, and to mitigate vertical polarized disturbances. Nevertheless I had problems to interpret the original measurement but thanks to all input I have gained more insight, as I hope many others also have.
73/Torbjorn/SM6AYM
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Re: Where did OneOfEleven go
It's updated on a regular basis - so make sure you have a look at the current version about once per day.
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On Wednesday, September 9, 2020, 12:32:13 p.m. EDT, Brian Morrison <bdm@...> wrote: On Wed, 2020-09-09 at 18:28 +0200, EB4APL wrote: Hi,
Where I can download NanoVNA-App for Windows?? I'm trying to find it
several days but I can't. -- Brian
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Re: Where did OneOfEleven go
On Wed, 2020-09-09 at 18:28 +0200, EB4APL wrote: Hi,
Where I can download NanoVNA-App for Windows? I'm trying to find it
several days but I can't. -- Brian
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Re: Where did OneOfEleven go
Hi,
Where I can download NanoVNA-App for Windows?? I'm trying to find it several days but I can't.
Thank you,
Ignacio, EB4APL
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El 07/09/2020 a las 5:58, DiSlord escribi¨®: In NanoVNA-App, press button 'Upload Firmware'
In dialog box you can select, or load custom from file, or use 1-of-11 or my v1.0.26 build in app.
Warning!!!! Not upload wrong firmware, if you not instal quartz, select only LSI variant
--
El software de antivirus Avast ha analizado este correo electr¨®nico en busca de virus.
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Re: NanoVNA vs. MFJ-259B Antenna Analyzer
Yes, indeed! Again, the NANOVNA's are the best piece of test equipment to
enter the amateur market (and some professional use as well) since the
hand-held DMM. And, again, its a wonderful educational tool. And, again,
at a very affordable price.
I'll terminate the comments before bad-mouthing MFJ...............??
Dave - W?LEV
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On Wed, Sep 9, 2020 at 4:01 PM OneOfEleven <cmoss296@...> wrote: I just watched VE3OSO's comparison video and had a chuckled at the end lol.
I've been thinking for a while just how peed off MFJ must be now that we
have these extremely useful little VNA's, especially with how much they
cost. MFJ's sales must have taken a hit I should imagine.
--
*Dave - W?LEV*
*Just Let Darwin Work*
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For an open/short the VSWR is (mathematically) infinity. Displaying that is a practical limitation. Instead, you might look at dB(|S11|) or the Return Loss which should be right around 0dB after a calibration. Or, just |S11| (in linear units) which would ideally be 1.0. Of course, all this to within practical limits which, if you're within 1% of 1.0 that's a 40dB return loss and pretty darn good for most every application.
Hope that helps!
Darrell -- AF5FX
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NanoVNA vs. MFJ-259B Antenna Analyzer
I just watched VE3OSO's comparison video and had a chuckled at the end lol.
I've been thinking for a while just how peed off MFJ must be now that we have these extremely useful little VNA's, especially with how much they cost. MFJ's sales must have taken a hit I should imagine.
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Re: Transmission Line Tools
TNX Maurizio, that did the trick on my win7 machine except the drawing of the tuner it's missing " Form2Network3.bmp " that I am assuming it makes but have no clue where it hides it
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Re: Transmission Line Tools
Hi Perdard , I get also the same error message on Windows XP sp3 .
After that , I dowloaded the TeeChart5.ocx , and put it in the same directory of the application , and the program is working .
Another problem is that is not possible to draw the tuner. To do it the program needs some pictures.
Best Regards
Maurizio.
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Hi WB2UAQ and Oristo,
Thank you both for your response.
To begin with my Firmware spec of the NanoVna-H 4, I have version 0.5.0, Build time Feb 21 2020.
Before any cal I pressed RESET.
I have done three One Port calibrations in the following order:
1.??? OPEN-SHORT-LOAD -> result CAL OK
2.??? LOAD-OPEN-SHORT -> result CAL OK
3.??? OPEN-LOAD-SHORT -> result CAL OK
With "CAL OK" I mean that I have checked the measuring points of the SHORT, OPEN and LOAD in the Smith Chart.
As soon as a Cal Component Button is pressed then the text is reverse highlighted (text on black background), so I now understand that you can exactly see what you have pressed.
To put it to the test during the calibration I have deliberately mounted the SHORT to port 1 (CH0) and pressed the OPEN button.
So also pressing the SHORT button after mounting the OPEN.
As a result when connected the SHORT the dot was concentrated to the far right of the Smith chart.
My conclusion is that it makes no sense of the order in which you may use the cal components as long as you press the right button, so I suppose that the order does not matter.
Now I am anxious to the thought behind the green colored button below the button you had just pressed in the CAL menu during calibration.
Op 8-9-2020 om 04:09 schreef WB2UAQ:
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If the nano follows the HP network analyzers, it doesn't matter what the order is until after DONE is pushed.....even if you did one of the conditions over again.
Does it matter with the nano?
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Re: Transmission Line Tools
On Wed, Sep 9, 2020 at 08:08 AM, Perdad wrote:
Thank you for the nice suggestions !
Though I can't make the TLW3 to Graph anything on a modern Win10, get Run Time
Error 339.
I have tried all the different compatiblity modes but no luck. If anyone knows
how to fix this,
please give a hint.
)) Kind regards, Per
To install the update, you need the original TLW program from the ARRL Antenna Book CD installed on your computer. David AC?YW
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Re: Definition of resonance
Roger,
Very cool!
Impressive that you were able to very nearly duplicate his Smith chart
with a simulation.
And thanks for the pointers to TLD and TLW for transmission line analysis
in posts 17276, 17277.
Jerry, KE7ER
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On Tue, Sep 8, 2020 at 03:21 PM, Roger Need wrote: The second is a Smith chart. The one on the far left is at the antenna. The
second is after factoring in 17M of RG58C. The last is Torbj?rn's original
screenshot for comparison. Results are strikingly similar.
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Re: Transmission Line Tools
Thank you for the nice suggestions !
Though I can't make the TLW3 to Graph anything on a modern Win10, get Run Time Error 339.
I have tried all the different compatiblity modes but no luck. If anyone knows how to fix this,
please give a hint.
)) Kind regards, Per
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OK, my last update was way back in January and there have been a ton of enhancements to the commands on the device.I really need to? sit down and pull together all the new commands from the last 6 months.
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On Wednesday, September 9, 2020, 8:35:33 a.m. EDT, n9xcr@... <n9xcr@...> wrote:
Thank you, Larry! Yes, I looked through the command console doc, but on another web site. I'm not sure if it's the same, but I'll find the one here and take a look. Looking at Nanovna saver now.
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Thank you, Larry! Yes, I looked through the command console doc, but on another web site. I'm not sure if it's the same, but I'll find the one here and take a look. Looking at Nanovna saver now.
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Re: Definition of resonance
Everybody, this has been a grand discussion. It's great way to learn.
What is going on here is not opaque. The antenna does not consist of
two legs of 8 metres. That's all that's going on. One leg is 8 metres, yes, but the other leg is 8 metres plus the
length of the coaxial feed line (the feed line's braid). That leg has, in addition, a 90 degree dog leg at the feed point. To further muddy computations are reactive effects along that extra length of "antenna". On top of that, of course, we don't know about how that extra length, the braid, is "terminated". The 8 metre "radiating element" is being worked against a dog legged
counterpoise that has two arms of unequal length and a 90 degree bend. That's all. This is an off centre fed antenna of substantial complexity.
We also know nothing whatsoever about the "ground". At these
wavelengths what ground is and where it is becomes a large question. We don't know if the braid is somehow connected to that "ground" and, if so, how. There is no mystery. The instrument is being honest. It is simply
not looking at a dipole with 8 metre legs. It is looking into something far more complex. Mention has been made of isolating the braid at the feed point. Yes,
that can be done...sort of. The instrument tells us that it has not been done here. Even in the pure case, which a ham cannot bring about in his real world, please note that there will still be r.f. on the braid and not just common mode either; only on the page of a text book does the choke or whatever not leak or pass some r.f. By the way, consistently left out of attempts at computer modelling
antenna radiation patterns (mentioned earlier in this discussion) are the many conductors in the ham's house. Modelling all that would be excruciatingly difficult and time consuming but be very sure that Gertrude Stein was correct in saying that "a wire is a wire is a wire". At these wavelengths all that house wiring in its convoluted runs participates in the antenna's pattern and so in any analysis by instrument. John
at radio station VE7AOV
+++++ On 2020-09-08 3:21 p.m., Roger Need via groups.io wrote: I redid my simulation assuming that Torbj?rn Toreson did not use a current balun at the feedpoint. An additional antenna element that represented the outside surface of the coax shield was added. The output is as follows:
The first graphic shows the feedpoint impedance and SWR at the antenna.
The second is a Smith chart. The one on the far left is at the antenna. The second is after factoring in 17M of RG58C. The last is Torbj?rn's original screenshot for comparison. Results are strikingly similar.
Roger Need
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I was told it should be >9000 during calibration.
Darrell
Sent from my over-rated IPhone 7 Plus. Any Mis-spellings or grammar errors are due to my IPhone auto correct feature.
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On Sep 8, 2020, at 20:46, david.hostetler@... wrote:
?What do you expect the SWR of a short (or open) to be?
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Yes Sir. I reset it before recalibration.
Darrell
Sent from my over-rated IPhone 7 Plus. Any Mis-spellings or grammar errors are due to my IPhone auto correct feature.
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On Sep 8, 2020, at 20:24, David Eckhardt <davearea51a@...> wrote:
?Before you do any new cal., be sure to clear any past cal memories.
Dave - W?LEV
On Wed, Sep 9, 2020 at 1:20 AM Darrell Carothers <rescuemedic1@...>
wrote:
I have calibrated the VNA. With the short plug it shows 1:12.76 SWR.
After calibration if I reinsert the short plug it shows SWR of 1:9554.1 to
1:2147483647.47.
Is there away to do a hard reset back to factory settings? Or is it
bricked?
Any help would be greatly appreciated.
Darrell Carothers
Sent from my over-rated IPhone 7 Plus. Any Mis-spellings or grammar
errors are due to my IPhone auto correct feature.
--
*Dave - W?LEV*
*Just Let Darwin Work*
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What do you expect the SWR of a short (or open) to be?
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af5fx
Perdad
Darrell Carothers