How to tell if you have a bad NanoVNA

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  • Опубликовано: 21 ноя 2024

Комментарии • 149

  • @randyslaten299
    @randyslaten299 2 года назад +50

    Don't know if this is the best place to rant about this, but here goes...
    Make sure to select DISPLAY->CHANNEL = "S11 (REFL)", not "S21 (THRU)", for measurements like SWR and SMITH charts made on PORT 1 (S11).
    For HF calibration, use 1 MHz -to- 30 MHz stimulus range:
    STIMULUS->START = 1 MHz, STIMULUS->STOP = 30 MHz.
    By all means use a smaller range for higher accuracy if necessary.
    Always reset calibration data before performing another one: CALIBRATE->RESET.
    Perform Open-Short-Load calibration and save result:
    CALIBRATE->OPEN..SHORT..LOAD..DONE->"SAVE 0".
    All settings and calibration data stored in "SAVE 0" will be loaded upon power-up.
    Verify good calibration by placing Open-Short-Load devices on PORT 1 and observe that "dot" position appears at right-left-center on SMITH chart center axis.
    If calibration was done right at the SMA connector on PORT 1 but an open coaxial jumper and/or adaptor is later added, the SMITH chart will show a rotated arc instead of a "dot". By introducing an electrical delay the calibration reference plane can be moved to the end of the jumper/adaptor to compensate.
    Automatically: MARKER->OPERATIONS->E-DELAY
    Manually: DISPLAY->SCALE->E-DELAY = "value" (+/- nS or pS)
    Re-save to include in location of choice, e.g. "SAVE 0", "SAVE 1", etc.

  • @MidlifeRenaissanceMan
    @MidlifeRenaissanceMan 3 года назад +15

    I picked up a used Nano VNA F that had some similar issues. Buttons were all out of whack, but calibration was fine. I replaced the lithium battery and now it works like a champion. Problem free.
    Try replacing the battery, or giving it a reliable supply

    • @temporarilyoffline
      @temporarilyoffline  3 года назад +6

      Very good idea!

    • @TonyLing
      @TonyLing Год назад +1

      I've just tried unplugging the internal battery on mine and running off USB-C. No change observed.

  • @jeffreyfritz5866
    @jeffreyfritz5866 Год назад +6

    You have descirbed exactly the way that my NanoVNA is acting. It acts like your bad one. R&L is replacing it with a newer version. Your video and testing was immensely helpful! 73

  • @Number4lead
    @Number4lead 2 года назад +7

    I bought a nano VNA on amazon. I have attempted to build several antennas from quagis to moxons to j poles. My vna always measured poor to mediocre performance. I always assumed I did something wrong, although I measured everything to a T. Now I'm wondering if my vna is faulty all this time. I'm going back to the good old reliable SWR meter.

    • @temporarilyoffline
      @temporarilyoffline  2 года назад +4

      I've been happy with the aursinc label on Amazon. You could try a second one for something to compare too and return it if it doesn't work as expected. The Nano has so much functionality (when it works), but the cloners have gotten ugly. Amazon link: amzn.to/3ezESBc

  • @astrawally8448
    @astrawally8448 7 месяцев назад +2

    My biggest learning with these is that you need to be wary your own interactions and how they impact what you are measuring (capacitive coupling, induction effects etc), how well it is shielded (your Norcal looks hip but it is not shielded) and any grounding effects.
    The NanoVNA uses a few mW of power to make its measurements/sweeps, it doesn’t take a lot of interference to impact those.
    To show this, get your good NanoVNA and connect a known good VHF/UHF whip. Find best VSWR and start to interact with it.
    Point here is that there are so many factors at play that it is going to be difficult to blame the NanoVNA purely.
    I do agree with the other comments about battery and firmware updates but I don’t believe that any one supplier or manufacturer is intrinsically building dud hardware beyond the odd faulty units.

  •  7 месяцев назад +3

    You should set the stimulus, or change the band before calibration.

  • @barrykery1175
    @barrykery1175 3 года назад +1

    My NanoVNA H4 is build time Jan 31 2021 Version 1.0.45 and I don't have any issues at all. I have a RIG Expert AA-230 Zoom, AA 650 and a SARK 110. All four give me pretty much the same readings. This is not the firmware version that came with mine. I bought mine from R&L Electronics thinking they did their research before they went out and bought junk. I also purchased the TInySA from them. The TinySA had a slight glitch on the display on 40 meters when I narrowed the span down to 10 khz. I updated the firmware and the little glitch went away.
    Your video was very interesting and glad you posted it.
    Barry, KU3X

    • @temporarilyoffline
      @temporarilyoffline  3 года назад +1

      Thanks Berry! I wish it was easier to spot the "fake"... but it could have also had an ESD or something... I'm holding on to it for fun.

  • @jamescoleman4747
    @jamescoleman4747 2 года назад +5

    Try and remember to ground the coax before connecting your vna or other kit.

    • @temporarilyoffline
      @temporarilyoffline  2 года назад

      That's a great idea!

    • @ronalddang7507
      @ronalddang7507 Год назад

      If you're using a regular stick antenna on an HT, do you need to ground it? If so, how?

    • @temporarilyoffline
      @temporarilyoffline  Год назад

      Usually you are the ground in an HT. But you can add a "tiger tail" and get greater range. When you take the antenna off the HT to test, you need to replace that missing human factor.

    • @ronalddang7507
      @ronalddang7507 Год назад

      @@temporarilyoffline I see, so how would one replace that "human" factor? Sorry if these are simple questions, I'm quite new to electronics myself

    • @temporarilyoffline
      @temporarilyoffline  Год назад

      ​@@ronalddang7507 No problem with the simple questions, that's what I'm here for. That's the "tiger tail" I mentioned earlier. Check out this short from my buddy Hayden - Ham Radio DX channel:ruclips.net/user/shortsccJHdmSE7D4
      What are you trying to accomplish? testing the antenna on the nanovna?

  • @ToNzHoLtZ
    @ToNzHoLtZ Год назад +1

    My nano vna was glitching until I installed the new firmware, and it now seems to work okay, except for the fact it does not have a DTF option ..

  • @tomstrum6259
    @tomstrum6259 Год назад +3

    Can't believe you opened up your buddies Vna & pulled shielding cans off !!

    • @temporarilyoffline
      @temporarilyoffline  Год назад +3

      When it starts out broken, you've got nothing to lose! :-D

    • @izzzzzz6
      @izzzzzz6 Год назад +1

      lol

    • @TonyLing
      @TonyLing Год назад +1

      The shielding cans thankfully are not soldered in place, and pop on and off very easily

  • @bertbronson8395
    @bertbronson8395 9 месяцев назад

    I am curious as to why the curves werent flatter given the swr was set to 1.0/ division on both devices (later in the video) instead of the 250m/ division you had on your device at the beginning of the video. 1.0/ gives a full range of like 10 vs 250m/ a vertical range of 2. That may not affect the readings or results, but it is curious...

    • @temporarilyoffline
      @temporarilyoffline  9 месяцев назад

      I don't remember changing that setting either...

    • @bertbronson8395
      @bertbronson8395 9 месяцев назад

      @@temporarilyoffline 1.0 is the default setting. The IMSA guy goes thru that on his 'intro to the nanovna' video - thats the only reason I know that - had no idea what SWR was used for at the time LOL.

  • @n8mail76
    @n8mail76 Год назад +6

    I've had mine for several years now. I've always made excuses for why it sucked. It works. But it makes you pay patience to get results

    • @temporarilyoffline
      @temporarilyoffline  Год назад +3

      I have a second one that works well.I use it a lot and it is great.The one in this video just seems to be a fake.

  • @rilosvideos877
    @rilosvideos877 10 месяцев назад

    I am missing the red thread in test test procedure - looks more like try and error. Its essential to have proper shielding in place (esp. for higher frequencies) and to have a proper calibration first. When i buy from ebay or ali how can i know what i get? You probably should omit the lowest price offerings ;-)

  • @peterdekeles.
    @peterdekeles. 3 года назад +5

    Would love to see a video on updating the firmware

    • @temporarilyoffline
      @temporarilyoffline  3 года назад +4

      Its on the table. I found a really good firmware to install during this diagnostic process. I'm very impressed with how well it gets installed and the "polish" it puts on the device. It just seems like the creator thought about the interface a bit and rounded off the rough edges.

    • @peterdekeles.
      @peterdekeles. 3 года назад +3

      @@temporarilyoffline I look forward to it. Thanks Steve

  • @DonzLockz
    @DonzLockz 2 года назад +1

    what was the end result? Did you return it?

    • @temporarilyoffline
      @temporarilyoffline  2 года назад +2

      This one was a fake, it was also a channel donation and I've kept it hoping that I can fix it someday. I need to do a firmware update on it to use a 3rd party firmware and see if that helps among other things. If your a ham and you're bored... you're doing it wrong!

    • @bryantwalley
      @bryantwalley Год назад

      @@temporarilyoffline all the components in these are relatively cheap to begin with. I would be curious to know if it was truly a fake or if they (Chinese manufacturing) are just buying components in bulk and relying on the law of averages to produce good ones and just accepting that they may have to eat a few returns.

    • @temporarilyoffline
      @temporarilyoffline  Год назад

      @@bryantwalley This is exactly how I feel about the MMDVM boards - we bought about a dozen of them from Aliexpress and half didn't work - requiring some surgery, etc. Finally I got tired of being QA and just ordered a complete unit from a known brand on amazon. I paid more, but I knew it would work when I got it... and it did.

  • @Screamingtut
    @Screamingtut 3 года назад

    mine comes up with the Blue logo like your friend's NanoVNA. I cannot read the version because I did not have my reading glasses handy.

    • @temporarilyoffline
      @temporarilyoffline  3 года назад

      There are a lot of different versions of the firmware out there.

  • @PhilLeith
    @PhilLeith Год назад

    I have one a friend gave me ... and I am getting results I would not expect. SWRs in the 10:1 range in the range this dipole is cut for. I'm thinking maybe it's a bad one

    • @temporarilyoffline
      @temporarilyoffline  Год назад

      I had to run a side by side comparison with another analyzer to prove it

  • @Tommyr
    @Tommyr 2 года назад

    I just bought one on Amazon and can return it if it doesn't work right within 30 days. Need it for VHF/UHF antenna testing. I already have an AA-55 zoom for HF.

    • @temporarilyoffline
      @temporarilyoffline  2 года назад

      It's a great gadget at a great price

    • @izzzzzz6
      @izzzzzz6 Год назад +1

      it only goes to 1 Ghz i think. Better get a newer vs they go much higher in frequency.

    • @Tommyr
      @Tommyr Год назад

      @@izzzzzz6 I don't need one that goes higher.

  • @vidasvv
    @vidasvv 3 года назад

    How does it compare if u slap a 75 or 100 ohm load ? tnx 4 the upload! 73

  • @bill-2018
    @bill-2018 11 месяцев назад +1

    I also experienced having to press the screen several times. I think in my case the battery voltage was a bit too low as it seems better now I keep it topped up after every use no matter how short.
    G4GHB.

    • @temporarilyoffline
      @temporarilyoffline  11 месяцев назад

      Thanks Bill! Looks like you've got a good answer.

  • @xiaonguyen6693
    @xiaonguyen6693 11 месяцев назад

    great video, love the adhd extras :)

  • @Randy-xs4wm
    @Randy-xs4wm 3 года назад +1

    I actually need to buy a NanoVNA and would appreciate your recommendation (link) for which one to buy. By the way, affiliate links are ok with me (because the price doesn't increase for me if I use a link you sponsor, AND I get to support your efforts as well)!

    • @temporarilyoffline
      @temporarilyoffline  3 года назад

      Thanks, there is a link for R and L electronics in the description

  • @TonyLing
    @TonyLing Год назад

    Can it actually be counterfeit? I understand that it is an open source design.
    My H4 behaves in a similar way. The interface can be unresponsive, and the measurements are not consistent. I think I'm going to buy a V4.

    • @temporarilyoffline
      @temporarilyoffline  Год назад +1

      Counterfeit in the sense that it was made and sold by somebody that didn't know what they were actually making.

  • @user-uv4xe3cq2y
    @user-uv4xe3cq2y 7 месяцев назад

    Before jumping to conclusions, replace the battery with a fresh one. Tnx for the video.

  • @derbemobile
    @derbemobile Месяц назад

    Weird. Now mine works but Bill's doesn’t 😂

  • @bulldogloverlover5496
    @bulldogloverlover5496 Год назад +2

    Incredibly long and not very clear. It was so long I forgot exactly what we were comparing.

    • @temporarilyoffline
      @temporarilyoffline  Год назад +1

      Good thing there are chapters on the video.

    • @TonyLing
      @TonyLing Год назад

      It is nobodies fault but your own that you have a short little span of attention

  • @prestonshute7243
    @prestonshute7243 2 года назад

    Had to send mine back to Amazon, it was doing lots of strange thing. The screen was not operating correctly, lots of retouches on back. Did not agree with either MFJ meters. So I did a screen cal and that made it even worst. So back it went and they gave me full refund to my account. That unit was about $105.00.
    I may try buying another 🤞
    73
    Wd4dda

    • @temporarilyoffline
      @temporarilyoffline  2 года назад

      I got a second one and it has been good to me. The fakes are a problem. Glad to hear you got your money back with no hassles.

  • @djdommes9302
    @djdommes9302 2 года назад

    How about scale setting ?

    • @temporarilyoffline
      @temporarilyoffline  2 года назад

      Wouldn't that have returned to "normal" after a factory reset?

  • @darylcheshire1618
    @darylcheshire1618 4 месяца назад

    You can re-calibrate the touch screen.

  • @uzaiyaro
    @uzaiyaro 5 месяцев назад

    Calibrate the touch screen if you're having problems with the touch.

    • @temporarilyoffline
      @temporarilyoffline  5 месяцев назад

      I did that in the video.

    • @uzaiyaro
      @uzaiyaro 5 месяцев назад

      @@temporarilyoffline I must have skipped over that part, and I must have had good luck with mine for a moment because it started being touchy again (pardon the pun) after I wrote this comment. I’m trying a firmware update tonight and will see if that has any effect. It’s not my nano anyway, so this might just push me towards a non-clone if I can’t get it to cooperate.

  • @izzzzzz6
    @izzzzzz6 Год назад

    I just picked up a nano for €45 inc. delivery. Hoping it's a good one. It's white.

  • @ur5gqf
    @ur5gqf 7 месяцев назад

    Купи очки, там масштаб scale/div разный на графике swr. Видно же что одинаковые платы...

  • @frequencywatchers
    @frequencywatchers Год назад

    I Have My NanoVna Working Good, But The First Thing I Did I Changed The Basttery So Now It Works 3 Times As Loonger On A Field :)
    Sorry For You problem, Maybe I Can Figure It Out If I Put My Mind To It, Sadly I Would Have To Have Your VNA To Figure TThe Problem Out, I Bet Its Easy One:)

    • @temporarilyoffline
      @temporarilyoffline  Год назад

      I'm open to any suggestions!

    • @frequencywatchers
      @frequencywatchers Год назад +1

      @@temporarilyoffline Well, You Can Send It To Me And I Can Try To Fix It And Send You Back The VNA, I Have Some Smart Heads Over Here To So I Will Not Be The Only One Figuring Out Your Problem And We Could Maake Videos About This Thing :) I Can Make A Video How I Figured Out The Problem And You Can Make A Video About How Its Changed And Whats Changed And What You Are Doing With It Now And All That Stuff :) Ofcorse You Will Be Allowed To Use My Footage In Your Video Aswell To Show What You Want To Show

    • @temporarilyoffline
      @temporarilyoffline  Год назад

      Message me on the discord or via email

  • @curtw8827
    @curtw8827 Год назад

    I've learned that updating firmware sometimes results in a brick.

  • @tmiller9099
    @tmiller9099 2 года назад

    Do you need to set the range/stimuls before calibration?

    • @temporarilyoffline
      @temporarilyoffline  2 года назад

      Yes, you should set it to what interests you in the testing you're doing. Gotta ask the right questions to get the right answers.

  • @rickeaston3228
    @rickeaston3228 2 года назад

    Why did you keep it? I would have sent it back when the screens would not come up right. Why? It could be a legit unit but broke or it's a crummy clone. Either way, you should have gotten rid of it. It also has a dim display. Not very bright.

    • @temporarilyoffline
      @temporarilyoffline  2 года назад +1

      I kept it because a friend sent it to me and one day I might learn of a way yo fix it.

  • @dannelson8556
    @dannelson8556 Год назад +4

    By far the number one killer of nano VNAs is static discharge.
    hams unfamiliar with working with VNAs will foolishly connect their VNA to an outdoor antenna without a pad or without discharging any static on the center conductor and poof goes the front end of your VNA. If you did this in a laboratory with $100,000 VNA you get fired and sued for the cost of the repair.
    vector Network analyzers are generally considered laboratory grade equipment not field equipment so they almost never have protection against static discharge. It is expected that the user is properly trained in their operation and knows how to discharge any static charge before attempting to connect the DUT.
    So several mistakes I see in your video, one is you connected an external antenna to lab equipment without properly discharging any static buildup. two you connected lab equipment to an external antenna without an appropriate DC blocking pad You should always use a 3db DC blocking pad on the front end of your VNA.
    And of course one of the very first things to look for when experiencing erratic performance with microcontroller devices is input voltage. In other words you need to check your battery' voltage as low voltage or inability to supply the required current can cause erratic performance. As a ham radio operator I would expect you to already know this.

    • @temporarilyoffline
      @temporarilyoffline  Год назад +1

      You give hams a bad name.

    • @tmillsaz
      @tmillsaz 2 месяца назад

      He is just one of those Sad hams

    • @temporarilyoffline
      @temporarilyoffline  2 месяца назад +1

      It's all in the delivery. "You should have known this" vs. "hey, you might not know this, but..."

  • @richardblanchard2743
    @richardblanchard2743 11 месяцев назад

    You didn't say what scale you have in swr per division.

  • @daviddahlgren9603
    @daviddahlgren9603 Год назад

    Is that a dent in the case ?

  • @KingLoopie1
    @KingLoopie1 2 года назад

    If you have time, or a friend that has a hot air reflow station... You might want to try reflowing that board and cleaning it before updating it again. 👍

    • @temporarilyoffline
      @temporarilyoffline  2 года назад +1

      Good idea! So much to do in this hobby!

    • @KingLoopie1
      @KingLoopie1 2 года назад +1

      @@temporarilyoffline you ain't a lying there!

  • @DirtyPlumbus
    @DirtyPlumbus Год назад +1

    About 10 minutes into dealing with this the 24oz hammer would have come out and put the VNA to bed.
    Lol

    • @temporarilyoffline
      @temporarilyoffline  Год назад +1

      Sometimes you just have to know for sure...

    • @DirtyPlumbus
      @DirtyPlumbus Год назад

      @@temporarilyoffline I get that, but after reloading firmware you have to start asking yourself if you're gonna replace components on it or if it's better to just spend $60 on a new one from a different seller.
      Made for an interesting video anyway.

    • @temporarilyoffline
      @temporarilyoffline  Год назад +1

      I bought another one anyway. Needed a control for the test!

    • @DirtyPlumbus
      @DirtyPlumbus Год назад

      @@temporarilyoffline you got me hoping the one I just ordered isn't junk. Lol
      Honestly didn't even cross my mind before the video. Atleast now I'll have an idea of what to look for. Thanks

    • @temporarilyoffline
      @temporarilyoffline  Год назад +1

      @@DirtyPlumbus no problem, good luck!

  • @BigDamGun
    @BigDamGun 5 месяцев назад +1

    Hey dude, set the stimulus first before cal and your problems will go away and you won't waste the
    viewer's time ...

    • @temporarilyoffline
      @temporarilyoffline  5 месяцев назад

      I realize you don't have the staying power to get to the point in the video where do the exact thing you accuse me of missing... let me make it really easy for you: 14:26

  • @stevetotaro3219
    @stevetotaro3219 2 года назад +3

    Why am I half way through the video and have no clue how to tell if I have a bad NanoVNA?

    • @temporarilyoffline
      @temporarilyoffline  2 года назад +1

      Check the description for chapters

    • @stevetotaro3219
      @stevetotaro3219 2 года назад

      @@temporarilyoffline You could have made a 30 second video. Compare your suspect VNA against a known a good VNA.

    • @temporarilyoffline
      @temporarilyoffline  2 года назад

      Your right, I could have.

    • @stevetotaro3219
      @stevetotaro3219 2 года назад +4

      @@temporarilyoffline You HAM guys really love the sound of your own voices. Bunch of chatty Kathies

    • @k94536
      @k94536 Год назад +2

      @@temporarilyoffline nooooo the more info the better thank you k6rys

  • @dombernal1399
    @dombernal1399 2 года назад

    Use a HB pencil as a stylus.

  • @rojirrim7298
    @rojirrim7298 3 месяца назад

    Great video on how NOT to test if the device is broken or not because you're comparing decimals of SWR against an antenna that only you happen to have. FYI, they sell such things as "RF Demo Kit" VNA test PCBs at 5€ a piece in online stores, which you can actually use to compare against the known reference circuits of the PCB.
    By the way, you're doing the callibration at the plane of the PCB's output directly, and then you're attaching the antenna using an extension cable, so your callibration is bollocks if you don't add the extra E-Time on the settings to compensate for the increased length of conductor... Please, don't make videos talking about things you really don't know about with certainty, because often you'll end up spreading myths and false ideas. 41k people watched the video and are now left wondering whether they have a faulty NanoVNA without any real evidence from what I've seen that there are brands making copies with false hardware.

    • @temporarilyoffline
      @temporarilyoffline  3 месяца назад

      Great comment on how NOT to make comments on a youtube video. If you don't understand the concept of the test, don't bother making comments. You'll only end up spreading myths and false ideas. Not many will read your comment, but those that do will probably point out that even the original manufacturer of the NanoVNA indicates there are faulty clones.

    • @rojirrim7298
      @rojirrim7298 3 месяца назад

      @@temporarilyoffline Thanks for not answering to my point about your calibration being faulty since you made it at the plane of the NanoVNA and not of the DUT. As for the clones being "faulty", it's more about a clash between the original makers splitting and one of them remaking the design and selling it to a chinese factory, but the devices they make still work, albeit with more noise than the $300 alternative that the original makers offer...

    • @temporarilyoffline
      @temporarilyoffline  3 месяца назад

      If you understood the concepts laid out in the video, you'd know that the DUT is the NanoVNA, not the antenna. You'd also understand that even if the viewer didn't have the antenna I have, they could repeat the A/B comparison of the NanoVNA with any antenna, or even a dummy load. Just because you don't have all the facts or understand the concepts laid out in the video doesn't make /me/ wrong.

  • @nortonics5745
    @nortonics5745 4 месяца назад +1

    Next time please take your meds first.

  • @A_scope
    @A_scope 4 месяца назад

    its most likely the bms and a failing lipo

    • @temporarilyoffline
      @temporarilyoffline  4 месяца назад

      Interesting idea! Just not enough voltage to make it run well enough?

  • @baconsledge
    @baconsledge Год назад

    Pretty much cannot conclude anything.

  • @yavamaystudio8045
    @yavamaystudio8045 6 месяцев назад +1

    I had Hughen version, ...Very bad, 🤯 freazing, send back for refund

  • @MountainMan7.62x39
    @MountainMan7.62x39 7 месяцев назад +1

    Whats wrong with you. Whats wrong with you. Asked three times, whats wrong with you. Oops missed asking whats wrong with you. Oops missed asking whats wrong with you again. Oops missed asking whats wrong with you again for the third time. Opps, didn't need to ask whats wrong with you, intended to ask something else.

  • @domfilap8477
    @domfilap8477 Год назад +1

    Well that was a waste of 10 minutes.... told me nothing!

    • @temporarilyoffline
      @temporarilyoffline  Год назад

      Some people's kids man

    • @TonyLing
      @TonyLing Год назад

      Yes Dom, you could have been giving it the five fingered knuckle shuffle for 10 minutes instead

  • @dxidansv1321
    @dxidansv1321 Месяц назад

    Why do you set such a short span not even 1mhz?

    • @temporarilyoffline
      @temporarilyoffline  Месяц назад

      The device can only collect so many samples, the wider span you choose the less precise it is. Either way, what really matters is that the devices both ran the same tests and got (or didn't) the same results.

    • @dxidansv1321
      @dxidansv1321 Месяц назад

      @@temporarilyoffline oh i get it..