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Possible adjunct to 2.8" NanoVNA for outdoor use - LCD viewfinder
My friend Rich K0ZX has been using his NanoVNA (original type) outdoors, and asked me about options for improving display visibility. I went searching for possible solutions and ran into a low-cost camera viewfinder accessory (some digital cameras also have ~2.8" LCD display, and are subject to the same visibility impairments when used outdoors.)
A few weeks ago I ordered on ebay the 2.8" LCD viewfinder listed below (now about USD 12; they seem common on ebay and I'm sure there are alternatives to consider...) It arrived after about a month, and after popping out (inverting) the rubber material eye cup (it's shipped in a backwards configuration reduce size of shipping container) and placing it on my (very much original-era NanoVNA), it does indeed somewhat magnify the display and shield it from ambient light. A few of caveats: 1. The touchscreen is obviously not accessible while the viewfinder is in place, and my nanovna is pure original vintage, no updates, so the manual button/switch controls leave more than a little to be desired; 2. The focus isn't quite perfect - it seems that it the small gap between the LCD plane and the viewfinder focus point caused by the PC board material takes the viewfinder slightly out of focus, but it's still quite readable, nonetheless; 3. There's no immediately obvious way to fix the viewfinder to the NanoVNA. In any event, I wanted to pass this along to our user hhcommunity to see if it inspires any further ideas. A few photos are attached. Please excuse the up/down inverted photos (photography hasn't been my thing since about 1962!) Comments and observations welcomed! 73 Dave WB0GAZ wb0gaz@... |
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Re: New H4 Model Received from R & L Electronics
On Fri, Jun 12, 2020 at 11:28 AM, John wrote:
* I am looking forYou can save the various plots as a graphics file in NanoVNA Saver by right clicking the window you are interested in. You can also change the axis scaling and popout the window to stretch it. There are many programs that will plot Touchstone files. All of the other NanoVNA PC programs (see wiki for list) import touchstone files. AntScope 2 will also import touchstone files and you can save the plots as a screenshot. There was a discussion of programs that import touchstone in this group earlier this month. Roger |
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Calibration kit modeling with nanoVNA possible?
#calibration
#linux
#octave
I found a web page
explaining how to compute the *calibration kit model coefficients* from .s1p files (Load, open, short) from your home made calibration kit.. Usually you get the .s1p files from a calibrate professional VNA. Is it possible to also use the .s1p files from nanoVNA-saver? For those who like to calculate themselves, following I describe the software setup under Linux. The residuals from the calculations are shown in a plot. Installation instructions for Ubuntu 20.04 in the Terminal + file browser: $ sudo apt install octave # Create a data path $ cd $ mkdir Install $ cd Install # Install Octave library NLopt $ sudo apt install octave-nlopt # Install calkit_model.m $ cd $ mkdir Install/IN3OTD_CalKit $ cd Install/IN3OTD_CalKit # download calkit_model.m from Here is a "script": click on script and download in folder IN3OTD_CalKit # install sbox # copy sbox.zip to folder IN3OTD_CalKit and "expand here" # copy file nanoVNA1_Load.s1p to folder IN3OTD_CalKit # now run a calculation: $ octave # set path to package sbox (S-parameter toolBox) octave:1> addpath('sbox/sbox'); octave:1> calkit_model('nanoVNA1_Load.s1p','LOAD') offs_delay = 43.648469 ps offs_loss = 0.000000 Gohm/s offs_Z0 = 49.986443 ohm Residual RMS error : -44.357936 dB Octave_CalKit-model-LOAD_nanoVNA1.png octave:1> calkit_model('nanoVNA1_Open.s1p','OPEN') offs_delay = 11.793264 ps offs_loss = 0.744891 Gohm/s offs_Z0 = 54.943388 ohm C0 = -153.031826 * 1e-15 F C1 = -537.445705 * 1e-27 F/Hz C2 = -184.283709 * 1e-36 F/Hz^2 C3 = -69.580809 * 1e-45 F/Hz^3 Residual RMS error : -33.399417 dB Octave_CalKit-model-OPEN_nanoVNA1.png octave:1> calkit_model('nanoVNA1_Short.s1p','SHORT') offs_delay = 20.000000 ps offs_loss = 0.100000 Gohm/s offs_Z0 = 10.000000 ohm L0 = 0.000000 * 1e-12 H L1 = 0.000000 * 1e-24 H/Hz L2 = 0.000000 * 1e-33 H/Hz^2 L3 = 0.000000 * 1e-42 H/Hz^3 Residual RMS error : -30.112093 dB Octave_CalKit-model-SHORT_nanoVNA1.png The references 3 and 4 from the web page are changed to: Reference [3] Agilent Technical Forum, "HP 85032F Cal Kit" thread Reference [4] Agilent Technical Forum, "Type N cal kit data needed" thread 73, Rudi DL5FA |
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Re: RigExpert's PC software now Supports NanoVNA and is Open Source
#consolecommands
#measurement
#applications
On Fri, 12 Jun 2020 at 17:48, DJ7BA <dj7ba@...> wrote:
You can not avoid the need to calibrate virtually any VNA (RigExpert, NanoVNA, Keysight etc) if you wish to measure the actual complex impedance of an antenna because the impedance is changed dramatically by the connecting cable. If you only measure at the cable in the shack, then you are not getting as much information as you can. It is only being used like an SWR meter. 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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Re: RigExpert's PC software now Supports NanoVNA and is Open Source
#consolecommands
#measurement
#applications
Hi,
I would just like to share my experience. I got my NanoVNA-H4 two days ago. I did not have any install problems encountered by many and I do not exactly know why. My "operating conditions" for the install are: PC (from Start>>Settings>>About tab) - Windows 10 Home single language, version 1903, OS build 18.362.900; Antscope2 - v1.1.1; NanoVNA-H4 (from boot-up screen) HW version 4.2 Version 0.5.0 Build Time Feb 21 2020 - 12:55:37 Kernel 5.1.0 I installed Antscope2 directly after download (previously was the v1.1.0 which also installed without problems and that version also connected to my NanoVNA H4). As noted by others, there is a Settings tab when Antscope2 loads that says "Connect to NanoVNA." I just confirmed the correct COM port already filled out in the corresponding box (from Windows DeviceManager). Attached is a screenshot on the SWR tab of Antscope2 of the Cushcraft R7 antenna which was the DUT (I am repairing the R7 antenna which was given to me by another HAM. The whole mast bent with very strongs winds and the 40m and 30m traps were also bent. I have straightened the bent parts and am seeing its performance with the NanoVNA). The SWR tab of Antscope2 shows a sweep 0-30Mhz; the grayed out vertical bands on the frequency axis are the amateur bands (there is an option in the Antscope2 settings tab to select ITU Region) corresponding to my QTH ITU Region 3. The R7 antenna was designed to work at 7 bands (10m, 12m, 15m, 17m, 20m, 30m and 40m) and the SWRs at the corresponding bands are shown. There is still some tuning that is needed: the lowest SWRs do not fall within the necessary bands (grayed out areas)... To confirm/compare the measurements made by the NanoVNA, I attached an AWO7A meter to the R7 and made a manual scan of the 7 bands. I tuned the AWO7A meter to the frequency shown by the NanoVNA (as shown by Antscope2) where the SWR is lowest and compared the SWR reading of the AWO7A. Here are results (first SWR numbers are NanoVNA readings; second numbers are AWO7A readings) - 160m - 1.6095Mhz @ 5.71; 1.609Mhz @ 6.7 80m - 3.209Mhz @1.92; 3.209Mhz @ 2.6 40m - 7.0478Mhz @3.53; 7.048Mhz @ 4.1 30m - 9.9269 Mhz @2.33; 9.927Mhz @ 2.4 20m - 13.7657 Mhz @1.9; 13.765Mhz @ 2.0 17m - 17.6045Mhz @ 1.24; 17.605Mhz @ 1.2 15m - 20.8035Mhz @1.22; 20.804Mhz @1.2 12m - 24.9622Mhz @1.15; 24.963Mhz @ 1.1 10m - 29.7607Mhz @ 1.15; 29.761Mhz at 1.0 Attached also are picture shots of the readings per band. The results for the 80m and 160m are inconclusive, since the antenna was not designed for these bands. The Return Loss tab of the Antscope2 for the R7 antenna is also attached. The diagram is shown as POSITIVE dB (the NanoVNAsaver software has the option of POSITIVE or NEGATIVE dB). I could not find -if any- similar option for the Antscope2 to show the RL diagram in the more familiar NEGATIVE dB format. I hope this experience could be of help. The NanoVNA H4 with Antscope2 gives very helpful info for my needs as a hobbyist, as does the AWO7A meter. There are certainly more accurate tools available, but these already help tremendously. Also, it was noted that the Antscope2 does not say anything more (could even be less) than what NanoSaver says of the NanoVNA data. It is just good to have another PC software available. My two cents worth... 73s Gerry DU7EYG |
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Re: RigExpert's PC software now Supports NanoVNA and is Open Source
#consolecommands
#measurement
#applications
On Fri, 12 Jun 2020 at 09:01, DJ7BA <dj7ba@...> wrote:
Hi Dave, Hi It¡¯s an interesting question and the answer is that the affect of pin depth depends on things that 99% of people will not consider. But, in some limited cases, it can effect amateurs in ways unrelated to measurements. These are things to consider. 1) Agilent have produced a graph for at least one RF connector, where the affect of pin depth is determined by RF simulation. The research showed return loss will *not* be significantly effected below a few GHz. 2) The specification of the worse N are -0.04¡± to + 0.0000¡±. I would not want any connector precessed by any amount, as it can damage others. That was my concern with the RigExpert. 3) Apart from the RigExpert, I have never seen any N *chassis mount connector* or *adapter* with precession. So one is unlikely to find a precessed chassis mount connector or adapter. Even cheap ones from China seem okay. Others have reported seeing precession, but I have never personally seen any other *N* connectors with the problem. I believe modern manufacturing tolerances mean it is very easy to make connectors meet the specification. 4) When people assemble connectors on *cables*, there¡¯s a *huge* variation! If you look at a bunch of amateur assembled cables you will find pins well off centre and pin depths so different that you can see it with the naked eye. 5) Now what I personally think will be the most significant issue. If you are running high power, the heating of the inner conductor is likely to affect the power handling, so it could effect hams at low frequencies. I would want the male pin inserted as far as possible in the female to reduce the resistance and so heating. 6) If you look carefully at the design of N, SMA and 3.5 mm connectors, you should be able to work out that wear will cause the male to enter the female more, so wear on the outer is likely to improve matters - but the inner is likely to wear more, so I am *not* saying worn connectors are betters. 7) On precision 3.5 mm calibration standards, I have seen them go out of specification due to wear. The smaller connectors will wear more, and a precision connector will be closer to the limits to start with. Clearly if a calibration standard has a specification of -0.0005¡± / + 0.0000¡±, then wear on the outer conductor of 0.0005¡± or even less, will put it out of specification. On a typical SMA, which has the pin recessed 0.005¡±, much greater wear can occur before the SMA will go out of specification. 7) I have seen one precession Agilent N go out of specification. 8) The worse problems with cheap N connectors is the threads are poorly made, so wear on connectors is much higher than desirable. I have seen some N connectors where the thread appears to have been cut with an axe. Chinese N to SMA adapters - no gap specified. but surprisingly, my experience is that the Chinese connectors are okay. They know the tolerance on their manufacturing. If it is +/- 0.010¡± with a 95% uncertainty (2 standard deviations), then assuming a Gaussian distribution, designing for a gap of 0.02¡± will put the chances of getting one out of specification to be about 0.01% (4 standard deviations) 73, Hans Dave, G8WRB --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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Re: NanoVNA-H and AntScope2 Two part question
#applications
#firmware
Thanks Larry and Steve.
I am guessing that my NanoVNA2 is lost since it has been stuck now over a month in KY. |
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Re: RigExpert's PC software now Supports NanoVNA and is Open Source
#consolecommands
#measurement
#applications
On Fri, 12 Jun 2020 at 07:49, randmental <Randmental@...> wrote:
Dave, No, I did NOT choose not to get a refund! Personally I thought that the N connector looked pretty poor, was out of specification and should be returned. But the club chose not to. Yes, we did have the option of a refund. But what annoyed me with RadioWorld was that they would not swap it for another unit. I think they were totally unaware of what a connector guage was, and didn¡¯t want a fussy customer that might reject another. 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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Re: RigExpert's PC software now Supports NanoVNA and is Open Source
#consolecommands
#measurement
#applications
Hi Dave,
I saw your N Plug male pin gap measuring gauge pic. Thanks for it, I never saw such device before. Good point. I have both, the AA-600 and the NanoVNA, so a comparison is of interest. Question: Does that gap matter significantly below the AA-600 range of max. 600 MHz? I gueth, that AA-600 users, mostly working below 440 MHz, will not find significant differences because of this tiny little gap. I love my AA-600 and would buy it again. It is my most used tool. But I work mainly below 30 MHz anyway. I think, however, your subject is good to know for anyone using SMA to N Adapters with the the NanoVNA, too, especially if used with 1.5 GHz. Similar reasons apply. But it probably is much harder to find N adapters with warranted gap, not to talk about the extra SMA gap that the AA-600 does not have. I used what I could get, see pic: Chinese N to SMA adapters - no gap specified. 73, Hans DJ7BA -----Urspr¨¹ngliche Nachricht----- Von: [email protected] <[email protected]> Im Auftrag von Dr. David Kirkby, Kirkby Microwave Ltd Gesendet: Freitag, 12. Juni 2020 03:29 Cc: [email protected] Betreff: Re: [nanovna-users] RigExpert's PC software now Supports NanoVNA and is Open Source #applications #consolecommands #measurement On Fri, 12 Jun 2020 at 00:53, MICHAEL ST ANGELO <mstangelo@...> wrote: I would have followed up by contacting Rig Expert directly or via theThe item was purchased by a club. A decision was made by the members to ignore the problem. We were not willing to risk buying from the Ukraine, so would not have risked sending it to the Ukraine. If you read eham reviews on RigExpert products, you will see at least one comment that negative comments about their products get removed from the forum. For example G3GXG writes about some firmware suggestions. ¡° I tried sharing my concerns on the RigExpert site but every time I did, my comments were removed. This is clearly a raw subject for them.¡± Many of the issues raised here (connector specification, inability to input coefficients of calibration standards, risk of damage to precision connectors if mated with poor quality parts), are applicable to any VNA. 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 -- Diese E-Mail wurde von Avast Antivirus-Software auf Viren gepr¨¹ft. |
Roger Need
Dr. David Kirkby, Kirkby Microwave Ltd
N2BRG
