Re: Trouble buying from China
Stevepilot; It was being held. Apparently, no aircraft cargo space was available until just a very few days ago. -- *Mike* , K0JTA /g/Visible-Cell-Phone?°À³å(¥Ä)³å/?
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I would say NO.
Sorry to say, but have worked with VNA's for 30 years and as soon as you come near 1/8 wavelength the measurement errors are taking over.
You know, in the analyzer the matrices that are multiplied together, the error matrice will start to influence significantly. It is very difficult to say that it always will not work when exceeding 1/8 (because you are closing in to 1/4 and the matrice in play will get 0's and infinite in some places) because let's consider you are clever and you measure in a narrow sweep where your cable length is not any close to a 1/4 wave multiplum, then it can actually work to some extend.
Generally if you can't evaluate when you are measuring correct, I recommend you to keep your calibration point as close as possible to the analyzer and respect you might have significant errors if your CAL point exceeding 1/8 wave length away from the port.
People believing they can calibrate out 20 meter of coax at any frequency, does not have any idea what they are talking about.
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Re: What is the latest hardware version of NanoVna
#buying
Sorry the- H4 has a bigger screen and a lot of extra's in DiSlord firmware , I think you mean the H.
Op 19-5-2020 om 17:27 schreef Dragan Milivojevic:
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Way too expensive. The different versions are explained in the wiki:
/g/nanovna-users/wiki
Choice is practically between 3 versions: F (large screen), H4 latest
revision by Hugen of the original nano (small screen)
and "nanoVNA2" (S-A-A 2) that is a completely new project with better
performance but you will have to wait for it.
Safest bet is probably H4 directly from Hugen store.
On Tue, 19 May 2020 at 14:00, Andrea <sbarelman@...> wrote:
Hi to all
I would buy NanoVna but i'm little confused :) There are many version H- F....??
Any Advice ?
Thanks
or
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Re: Calibration standards - pl-259?
Calibration using SO-239 or PL-259 connectors is marginally useful at lower frequencies like the HF band because it is not an impedance controlled connector. The link below is the only commercial set I know of and they are UHF to SMA connectors with SMA loads attached which you can buy from Amazon much cheaper. A review of these Array Solutions cal loads was done by someone in this group. /g/nanovna-users/topic/71375643#11047You can make easily make better ones and there are several YouTube and web links that tell you how. Disclaimer: There are a couple of topics on this group that have discussed the disadvantages of using UHF (SO-239 and PL-259) connectors with the NanoVNA. /g/nanovna-users/topic/71097146#10935/g/nanovna-users/topic/71523607#11501Roger
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Re: Trouble buying from China
Question is Mike - why from 6th May to now to get to USA ? Hong Kong is the problem and has been pre Covid too :(
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Calibration standards - pl-259?
Does anyone have a source for a set of calibration standards on PL-259 / 239 connectors? Yes, I know I could ¡°make them¡±, but I¡¯d rather buy them! ;)
--
Regards,
Chris
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Re: What is the latest hardware version of NanoVna
#buying
Way too expensive. The different versions are explained in the wiki: /g/nanovna-users/wikiChoice is practically between 3 versions: F (large screen), H4 latest revision by Hugen of the original nano (small screen) and "nanoVNA2" (S-A-A 2) that is a completely new project with better performance but you will have to wait for it. Safest bet is probably H4 directly from Hugen store.
On Tue, 19 May 2020 at 14:00, Andrea <sbarelman@...> wrote:
Hi to all
I would buy NanoVna but i'm little confused :) There are many version H- F....??
Any Advice ?
Thanks
or
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Re: Is Gen11.TAOBAO nanoVNA upgradeable to 1.5GHz
Hi Dave. You can find the schematics in the Wiki in the Documentation section.
regards Bert
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Re: What is the latest hardware version of NanoVna
#buying
Then I would advise the -H4
Jos
Op 19-5-2020 om 14:31 schreef Bob Kircher:
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No matter which one the cost is so low not worth looking for lowest cost
bad clone. You will be happiest with the current Hugen NanoVNA-H the gold
standard as I understand it. Buy from Amazon or other reputable source.
Suggest you avoid Banggood.
Bob Kircher, K7QXY
Tigard, Oregon
503-789-3983
On Tue, May 19, 2020, 5:00 AM Andrea <sbarelman@...> wrote:
Hi to all
I would buy NanoVna but i'm little confused :) There are many version H-
F....??
Any Advice ?
Thanks
or
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Re: Is Gen11.TAOBAO nanoVNA upgradeable to 1.5GHz
Hi Bert thanks for the hardware information.
However .... I don't see some of the resistors mentioned on the only
schematic of the nanoVNA (12/29/16 @11:31AM) I can find.
I was interested to see which resistors needed changing before delving
inside. Is there an (earlier/later) schematic somewhere?
Dave
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On Mon, 18 May 2020 at 15:23, <bert_winkler@...> wrote: Hi Dave,
First You must upgrade the hardware of Your device.
- remove R29, R30 and R31
- replace R13 by 0 Ohm
- replace R9 by 200 Ohm
- replace R24 by 91 Ohm
- replace R22, R23 by 49.9 Ohm
- replace R25 by 11 Ohm
In order to use the full frequency range (10 kHz to 1500 MHz) You must
update Your Firmware.
Regards Bert
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I'd say that there is another requirement - range used for SOL calibration and range used for measuring should be identical! More precisely, calibration points and measuring points should be the same. This is less impactful if measuring range is relatively small (narrow) comparing to the "center frequency" (for example 14.000MHz to 14.300MHZ vs 3.5MHz to 29MHz), but still ...
With lengths approaching quarter wave length, things (impedance transformation) become very fast changing, and in my experience, interpolation between points where actual calibration was done done becomes much less accurate.
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Re: What is the latest hardware version of NanoVna
#buying
No matter which one the cost is so low not worth looking for lowest cost
bad clone. You will be happiest with the current Hugen NanoVNA-H the gold
standard as I understand it. Buy from Amazon or other reputable source.
Suggest you avoid Banggood.
Bob Kircher, K7QXY
Tigard, Oregon
503-789-3983
toggle quoted message
Show quoted text
On Tue, May 19, 2020, 5:00 AM Andrea <sbarelman@...> wrote: Hi to all
I would buy NanoVna but i'm little confused :) There are many version H-
F....??
Any Advice ?
Thanks
or
|
Re: What is the latest hardware version of NanoVna
#buying
|
What is the latest hardware version of NanoVna
#buying
Hi to all
I would buy NanoVna but i'm little confused :) There are many version H- F....??
Any Advice ?
Thanks
or
|
NanoVNA dealers in Europe?
With all the China problems, are there any NanoVNA dealers in Europe?
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Re: Trouble buying from China
I ordered pcbs that were ready at the end of March, they too got returned to the supplier for "security reasons".
Reshipped 4th April and they are still sitting in some warehouse in Shenzen waiting on the donkey to wake up and transport them to the airport.
Re the shipping out of Australia - pretty normal - our postal service is pretty crap at the best of times, I can get stuff from Germany quicker than I can get it from Sydney.
--
Terry VK5TM
( )
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Yes, assuming the antenna is connected at exactly the same point as your open, short, load were connected. If there's an additional "pigtail" at the antenna or anything like that, that will have an effect.
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If I connect the NanoVNA-H to a length of coax (about 20m of RG-11/U in this case) and perform an SOL calibration through the coax, will the NanoVNA then show me the feed point characteristics of the antenna to which the load end of the coax is connected?
Are there any other special settings that must be made?
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Re: Trouble buying from China
Update from Mike, K0JTA:
Picked up and processed May 6 in Hong Kong via DHL, and is now in "CINCINNATI HUB, OH - USA" at this time!!! -Looks as if I will have the shipment in hand VERY soon, unless there is a US Customs delay!!! (Woo-HOO!)
--
*Mike* , K0JTA
?°À³å(¥Ä)³å/?
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Re: Are any of the NanoVNA sold on Amazon any better or worse than any others? Is there a better U.S. site to order from?
How about the rampant misuse of "your" and "you're"?
---?
Ciao baby, catch you on the flip side
??
73 de W3AB/GEO ???
You can say "over", you can say "out", you just can't say "over and out".
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On Monday, May 18, 2020, 02:12:58 PM PDT, Rich NE1EE <ne1ee@...> wrote: What's a Grocer's Apostrophe? (humor) On 2020-05-18 17:01:-0400, you wrote: R&L said that there may be H4's stock this week!
randy.ab9go@... -- 73 de Rich NE1EE On the banks of the Piscataqua
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Mike K0JTA
Roger Need
Chris K2STP
Bob Kircher
Oristo
Jim Allyn - N7JA
GEO BADGER