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Re: Choke Series resonant frequency measurement
Thanks for the feedback and link Ady.
Once the cal is complete, the measurement plane is 50 ohms. Assume the cal is accurate and complete, the fixture will actually be a larger error contributor than the vna itself. It cannot be over emphasized that these large chokes must be measured in-situation as they are used. The parasitic present will be altered dependent on their placement. I had this vna running for some other work and took a look at one of these larger unmodified plate chokes. The first clockwise crossing is the standard SRF of the parallel resonate point. Sorry for the blur photo but you can see the 2- series resonance loops, one at ~ 15 MHz, the larger, and a second smaller one at 21 MHz. This second small loop is problematic. This measurement is taken with 401 date points. Use of the vna will require more than 101 data points to properly resolve the loops. Use of the feature in PC saver routine is required. Cal over several 100 points is necessary to achieve the loop signature clearly. Alan |
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Re: First PCB pictures of the V2
It would not. GPL:ed software does not care about the license of the hardware it runs on.
If it did, Dell and Lenovo would have to release the schematics and board files of their offerings running Linux out of the box :) Edy555 also released the schematics under a permissive license, but the pcb artwork was not released. Hugens NanoVNA-G is their original pcb artwork, even if it is firmware compatible with the original NanoVNA. Similarily thus NanoVNA 3ghz/SAA/v2 is original artwork. Only thing in common with other NanoVNA's is the name and firmware compability. |
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Re: NanoVNA connected to Amazon Fire tablet
hwalker- L.Rothman-
A couple of weeks after I bought the FIRE as it's only 4 months old yesterday. Amazon sent me a "Special Offer" to trade in my FIRE for the "Latest". I felt it was a "Bulk email" to all FIRE Owners on their list, which it was, but they never indicated #1 there was a problem #2 the problem will continue as new apps are released that take advantage of later versions of Android 5.. which was obsolete that day I bought it..I'm not sure but They were haaving a "PRIME DAY" and suckered me like they did Joe and Sally Sixpack.. What pisses me off more I gave away my 7 inch quad core Samsung to a deserving young lady who lost a baby to SIDS. She was here last weekend housecleaning for some Christmas money. I should trade back for the FIRE.. And I bought the fire with 64Gb RAM not 32.... Anyhow... 2 options - Amazon offers 7.3.1.1 as a download .bin file... Yet no instructions. How woul done install it and would it work, or did they change hardware. Both are Octo-cores.. I saw this too.. Has anyone tried it... the claims seem to indicate an advantage to where I am at with regard to being "Throttled" by Amazon. BUT- it does not change the level of my OS... My point being even if I "UN-Throttle" Amazon will the NovaVNA app run on OS based on Android 5... Here is the link: Merry Christmas to all, I'm leaving for the Airport, I'm schelping the family too cheap to hire an UBER driver today..relatives coming to town, bearing critizims and opinions galore..Tiz the season... reminder to self--Stop at Liquor store. The 3 beers I put in the Fridge after Field Days are hanging on the tree empty as of last night..... |
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Re: errors of "error" models
#90.04: Another one Estimated Value of Core Uncertainty in Z Measurement
- Continuing our guesses regarding the references of Gary O'Neil, N3GO : 23 December 2019 - /g/nanovna-users/message/8585 : ... but, on the other hand, if you ask if we can replace the legitimate - by the Decent Manufacturer of the Standards - S, L, O values, we chosen in our other program: #90: On the -Second- Arithmetical Method of Error Estimations in VNA Measurements - 22 December 2019 - /g/nanovna-users/message/8505 e.g. by the uncertainty values: S: 0.99*(cos(pi*(+178/180))+%i*(sin(pi*(+178/180))))$ L: -0.029*(cos(pi*0/180)+%i*(sin(pi*0/180)))$ O: 0.99*(cos(pi*(-2/180))+%i*(sin(pi*(-2/180))))$ which result to be the conjugates of the previous ones, then the answer is positive, simply because these values are also legitimated by the Decent Manufacturer of the Standards - they are within the uncertainty limit he provided to The Common User. By the way, the Core Uncertainty which is propagated from the Standards to Z, and was estimated in: #90.01 : Final Conclusion 22 December 2019 - /g/nanovna-users/message/8521 having its part values: ( Rt : +5% , Xt : +13% ) now, after the above replacement, results to also has the part values: ( Rt : - 5% , Xt : - 19% ) and so on... Sincerely, gin&pez@arg |
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Re: errors of "error" models
@Gary, N3GO
22 December 2019 - /g/nanovna-users/message/8572 Dear Gary, Well, these are interesting issues indeed, but we are not sure exactly where we have to look at, so we can only guess, e.g. if you are referenced at our positive conclusion: #89: On the Comparison of our Formulation with that by Erik, PD0EK" - 22 December 2019 - /g/nanovna-users/message/8494 , then you may have to take into account that our positive result : "true" is made possible only after we included in our program all the needed corrections to Erik's program - as we suggested with: @Erik, PD0EK - 21 December 2019 - /g/nanovna-users/message/8482 So, would you, please, be more specific regarding to what you are referenced at ? Best regards, gin&pez@arg |
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Re: NanoVNA Presentation
#measurement
#nanovna-saver
#tutorials
Nico going Luc! Good pictures as well.
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I will be doing something like that tonight :-) in Dordrecht, NL. I will be focussing on the Smith Chart in the nanoVNA and applications of that, skipping as much of the Math as I can. 73, Arie PA3A Op 23-12-2019 om 11:46 schreef Luc ON7DQ: Hi All, |
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Re: Screen replacement?
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
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 |
Ismo V??n?nen OH2FTG
Larry Macionski
gin&pez@arg
Arie Kleingeld PA3A
OwO
Dr. David Kirkby, Kirkby Microwave Ltd