Hi All,
Last friday, I gave a 4 hour presentation on the nanoVNA for the local radio club in Ostend, Belgium.
It was attended by over 50 people, see a short report here
A video will be posted online too (but needs some time editing, so be patient ...).
I uploaded a pdf with clickable links in the File section in a new folder "Presentations"
All is in the DUTCH language, but the pictures explain themselves (I hope) ... and Google Translate is your friend ;-)
If anyone wants to do the translation into English, mail me off-list for the original .pptx file.
(my address is good on qrz.com)
73,
Luc - ON7DQ/KF0CR
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Thanks for that good info. I ordered the 3.2" touch screen. Cost at present is 11 Euro. Thanks also to Herman, ON1BES, for upgrade documentation. I need no extension parts, as already I have a larger (hand ground eliminating, balun avoiding) 6mm PE board with N adapters. See pic. I only must make the larger cover frame. 73. Hans DJ7BA -----Urspr¨¹ngliche Nachricht----- Von: [email protected] < [email protected]> Im Auftrag von nanovnauser@... Gesendet: Sonntag, 22. Dezember 2019 00:02 An: [email protected]Betreff: Re: [nanovna-users] Screen replacement? just select the 2nd pic to get the touchscreen version.
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Re: First PCB pictures of the V2
If you can point out concrete examples with evidence of where we are "stealing intellectual property", you are welcome to bring the case to your local state department of commerce.
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Re: First PCB pictures of the V2
S-A-A (V2) hardware is a completely new design from scratch. There is nothing that's bears any resemblance to the edy555 design, except for the use of si5351 to cover low frequencies. We have innovated on several key parts of the VNA design such as the coupler design, and OwOComm will publish all design files in order to render the ideas unpatentable. We don't market or sell these devices, so we are not in control of what trade name they will be sold under (that's up to the distributors), and there is also no registered "NanoVNA" trademark.
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Re: First PCB pictures of the V2
On Fri, 20 Dec 2019 at 15:27, Gyula Molnar <gyula.ha3hz@...> wrote: Doesn't it bother you steal your other intellectual product? To my knowledge all of the developers are from China. Stealing intellectual property is very much a part of the culture. 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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Terry, just try another card.
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On Mon, Dec 23, 2019 at 6:39 AM Terry VK5TM <vk5tm@...> wrote: Found it on the english Aliexpress site, but when I went to pay they
started wanting jpeg scans of my credit card, drivers license and other
stuff.
They can stick that where the sun doesn't shine.
Terry VK5TM
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Re: Choke Series resonant frequency measurement
I agree Alan, GDO or equivalent should be the best method IMO also.
@Henry: If you use NanoVNA, it needs to be calibrated on a narrow freq
interval, it has only 101 points, easy to miss a deep resonance. Better use
NanoVNA-saver, which can calibrate with many more points (ie 2020)
*Still, nobody answered my question: is the stray capacitance (or impedance
in general) of the NanoVNA channels influencing the measured resonance
frequency of the choke, or the calibration is able to remove this
influence? *
I understand so far the choke is shunted by the 50 Ohm impedance (which is
not purely resistive) of the NanoVNA channels, which reduce Q but the
resonances should still be visible.
W8JI is describing a different method of measuring the choke:
It would be interesting to compare the various methods.
73 Ady YO2NAA
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On Mon, Dec 23, 2019 at 2:56 AM alan victor <avictor73@...> wrote: Yes, you need to place the choke in its position ON THE INTENDED AMPLIFIER
chassis. In this manner the exact distributive affects of shunt C are
properly noted.
And with all do respects to the VNA, I would much rather do this
measurement with a GDO.
Or... convert your vna into the equivalent of a GDO by exciting the ch 0
port into a small link coil which would utilize the measurement system as a
coupled transformer. Not unlike the GDO, coupling must be kept to a minimum
so that reduction in Q affect of the choke under test is minimized.
Note, you will need to measure both the anti resonate as well series
resonate points as you described. In the series mode, the choke is shorted.
Again, a direct connect of this arrangement to ch 0 would seem problematic.
Consider the vna system is placing 50 ohms in series with the choke under
test!
I would encourage you to correlate the measurements with the vna and with
the GDO technique before applying 4000 volts to that nice tube!
I would also consider if you have one... the classic chokes like the old
National Radio R175 which had strong series resonate problems in the 15
meter band. They would burst into flames! See if the vna points out the
alarm. You should be able to pick up both the series resonate and parallel
resonate signature on the vna-Smith plot. I know the GDO does pick up these
signatures and I have modified those chokes based on the GDO results to fix
their problems.
Alan
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New extended Tutorial Version 1.5. for the NanoVNA-H
Hello Friends,
I have my tutorial extended by a chapter "The NanoVNA-H used up to 1500 (1300) MHz" and uploaded to my Homepage ( www.gunthard-kraus.de) as Version 1.5.
The chapter contains also a 110 MHz LPF tested up to 1300 MHz as a practical example.
Have fun with it.
73's
Gunthard , DG8GB
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On Sun, Dec 22, 2019 at 05:56 PM, Gary O'Neil wrote:
. I would expect this to be true if the standards used in both were set equal
to ideal.
Being mathematical identical the standards being NOT ideal have identical impact, even the uncertainty regions will be identical. The formula I provided for comparison and is proven to be identical is the the standard 3 term calibration formula as also used in nanoVNA saver and TAPR-VNA. I have not yet checked if this formula is also used (without simplification) in the nanoVNA itself. For sure the nanoVNA does not allow to use fully characterized standards and therefore the mathematics inside the nanoVNA is somewhat simpler. -- NanoVNA Wiki: /g/nanovna-users/wiki/homeNanoVNA Files: /g/nanovna-users/filesErik, PD0EK
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Re: errors of "error" models
GIN&PEZ;
Am I correct in my interpretation of this that incorporating standards with correction has - in this particular case - moved the measured result closer to the higher of the uncertainty boundary limits? The implication being that the use of nominal values for the standards potentially minimizes the degree of uncertainty in the final measurement.
Is it possible that there is a sign error in how the HP correction terms are coded? Alternating signs would tend toward convergence on a nominal value, rather than divergence in a signed direction.
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73
Gary, N3GO
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Thanks Jeff;
Too many new tools tied to learning about this. I don¡¯t know which one to learn first. :-)
I¡¯m seeing universal agreement on the equivalence of the computations, so I¡¯m comfortable that I can set anchor for my understanding at this point.
I think the nuance that GIN&PEZ may be attempting to communicate; is the influence or perhaps lack of influence of calibration on the uncertainties in the final result.
They utilize what they define as differential error regions and intervals to predict the limits of uncertainty, and I think they are comparing measurements using nominal value estimates for the NanoVNA¡¯s OEM standards with measurements made using high quality HP standards and their respective characterized correction values. Those results are also evaluated to assess their containment within the predicted error region.
--
73
Gary, N3GO
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Erik;
The most recent posts by GIN&PEZ is shedding some new light on this. I am seeing additional data that leads me to believe that my understanding still remains somewhat off track. I also see hints of how the traditional approach may be different.
It raises a few more questions for me.
The calibration mathematics is making sense though, and I think I¡¯m not too far from understanding the process in better detail.
--
73
Gary, N3GO
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On Sun, Dec 22, 2019 at 11:32 AM, <erik@...> wrote:
In /g/nanovna-users/message/8494 they provide the proof they
are mathematically the same.
The GIN&PEZ equation certainly seems to give the same result as the standard one-port 3-term correction equations. Here's a quick Matlab example I wrote, using the GIN&PEZ terminology and values pulled out of the air for short, open, load, and measured DUT gamma: MATLAB CODE S = -0.9; % Actual Gamma of Short O = 0.9; % Actual Gamma of Open L = 0.1+1i*0.1; % Actual Gamma of Load s = -0.8+1i*0.1; % measured Gamma of Short o = 0.85-1i*0.15; % measured Gamma of Open l = 0.2; % measured Gamma of Load g = 0.5+1i*0.5 % measured Gamma of DUT % G will be the actual (calculated) Gamma of the DUT. % First, Gamma calculated according to GIN&PEZ Gginpez = (S*(L-O)*(g*s+l*o)+L*(O-S)*(g*l+o*s)+O*(S-L)*(g*o+s*l))/... ((L-O)*(g*s+l*o)+ (O-S)*(g*l+o*s) + (S-L)*(g*o+s*l)) % Now, Gamma calculated per 3-term one-port correction formulas: % (see equations 1, 5, 6, and 7 in the User Guide down-loadable from: % ) % First, four preliminary equations... D = S*(O-L)*s + O*L*o - O*L*l - (O*o - L*l)*S; e00 = -((O*l-L*l)*S*o - (O*L*o - O*L*l - (L*o-O*l)*S)*s)/D; e11 = ((O-L)*s - S*(o-l) + (L*o - O*l))/D; de = -((S*(o-l)-O*o + L*l)*s + (O*l-L*l)*o)/D; % And then the final equation calculating Gamma per 3-term correction: G3term = (g-e00)/((g*e11)-de) *** The Results *** Gginpez = 0.3288 + 0.7535i G3term = 0.3288 + 0.7535i Note: This is not a mathematical proof, but for this example the two methods of error correction give identical results. Which raises the question: For a one-port VNA, is there an advantage to using the GIN&PEZ equation over the standard 3-term error correction equations? - Jeff, k6jca
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I believe it is soldered, haven't bothered to look.
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Terry VK5TM
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I found this
2.8 inch 240*320 color TFT LCD touch screen with ili9341 driver IC touch panel | eBay
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2.8 inch 240*320 color TFT LCD touch screen with ili9341 driver IC touch...
Çý¶¯Æ÷IC£ºILI9341. ´øSPIµÄ 0.91Ó¢´ç80x160 sma ll tft lcd. S TFT lcd display fo. TFT TRANSMISSIVE. composed of a color TF...
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But it costs as much as a new nanoVNA.
Bob
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On Sunday, December 22, 2019, 08:39:46 PM PST, Terry VK5TM <vk5tm@...> wrote:
Found it on the english Aliexpress site, but when I went to pay they started wanting jpeg scans of my credit card, drivers license and other stuff.
They can stick that where the sun doesn't shine.
Terry VK5TM
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I looked at it and it's not clear just how it replaces the original screen.? Is there a connector you just swap, or what?? I would give it a shot to make for a bigger display.
I have had some trouble with AliExpress as well.? I am putting them on the bottom of my list of suppliers, along with Amazon.? So far Ebay is on top.
Bob K6DDX
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On Sunday, December 22, 2019, 08:39:46 PM PST, Terry VK5TM <vk5tm@...> wrote:
Found it on the english Aliexpress site, but when I went to pay they started wanting jpeg scans of my credit card, drivers license and other stuff.
They can stick that where the sun doesn't shine.
Terry VK5TM
( )
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Found it on the english Aliexpress site, but when I went to pay they started wanting jpeg scans of my credit card, drivers license and other stuff.
They can stick that where the sun doesn't shine.
Terry VK5TM
( )
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I was just going by the guy who said it was, specifically when he said it was a way to get QST issues.
Dave?? AB7E
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On 12/22/2019 8:07 PM, Jim Shorney wrote: Did you actually look at TinyCat/LibraryThing that W0RW uses? It is not a download or copying service.
73
-Jim
NU0C
On Sun, 22 Dec 2019 19:39:21 -0700
"stone_ridge_road" <xdavid@...> wrote:
the guy who thinks W0RW isn't engaging in copyright abuse
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Did you actually look at TinyCat/LibraryThing that W0RW uses? It is not a download or copying service. 73 -Jim NU0C On Sun, 22 Dec 2019 19:39:21 -0700 "stone_ridge_road" <xdavid@...> wrote: the guy who thinks W0RW isn't engaging in copyright abuse
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Not all.? I just think it's funny how easily people will rationalize their behavior, and I'm referring to the guy who started this thread as well as the guy who thinks W0RW isn't engaging in copyright abuse. ? Some of the other comments on free use have been informative for me, but I still think it's telling that nobody has thought to simply ask the author of the article for a free summary of his conclusions.
I don't know what links you referring to either .... I don't believe I've posted any relative to this thread.
73,
Dave?? AB7E
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On 12/22/2019 6:00 PM, Frank Howell wrote: Wow, Dave! You got in the bus very late, didn¡¯t you?
NONE of us are interested in this new QEX article for VNA theory! It¡¯s about the empirical comparison of the NanoVNA versus other higher grade VNAs. Do you get that difference? I¡¯ve got about a GB of books and articles (including the ones you¡¯ve put links to instead of actually reading this thread) on VNA theory, tutorials, user & service manuals, etc.
Way back on Saturday Night Live, Emily Litella used to get in the bus late, too. But when she caught on, she exclaimed, Never mind!
What¡¯s in your wallet? Lol
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OwO
Dr. David Kirkby, Kirkby Microwave Ltd
Jim Shorney