nanoVNA vs SVA1015X VNA (Need entry level VNA) - Page 1
Forum section: electronics / testgear

author: spacehen
author_rank: Contributor
timestamp: August 11, 2022, 11:14:04 am
content: I'm looking for an entry level VNA to add to my RF lab I am setting up. I already have a DSA815-TG spectrum analyzer so my question essentially is: is it worth the extra money to buy the SVA1015X which is also a spectrum analyser with limited VNA capability or should I just buy a nanoVNA. I need to make reasonably accurate S parameter measurements for amplifiers, filters and antennas from 10MHz to 1GHzThank you

author: tomud
author_rank: Regular Contributor
timestamp: August 11, 2022, 11:30:33 am
content: IMHO to buy SVA1015X is not very profitable in your case. As for nanoVNA, it depends on the model you want to buy. The first version is not very suitable if we are talking about measurements up to 1GHz (in fact, it works quite well up to 300MHz).I would consider nanoVna v2 plus4 (original only) or if you have more money to spend, you can buy libreVNA (IMHO A very good option). You can also think about selling the DSA815-TG and buying the SSA3021X Plus which can be converted to SVA1032X.Although if we're talking about the VNA itself, libreVNA will probably be the best choice (price / features / parameters) - especially since it's a full dual port VNA (gives the possibility of measurements S11/S12/S21/S22).As for the accuracy of the measurements, I will not answer here, it is too big a topic. Much depends on the device, cables, calibrators. You can find the technical parameters of all devices on the Internet, you have to see them yourself and answer the question if it is enough for you.

author: spacehen
author_rank: Contributor
timestamp: August 11, 2022, 12:27:59 pm
content: Maybe I should just save up and buy a proper VNA, thanks anyway.

author: joeqsmith
author_rank: Super Contributor
timestamp: August 11, 2022, 01:38:03 pm
content: Quote from: spacehen on August 11, 2022, 12:27:59 pmWith the very small bit of information you provided, I wouldn't suggest it due to the high costs. Rather wait until you learn enough to know what you need.For learning the basics, the NanoVNA is perfect. If damaged, the low cost allows them to be replaced. As suggested, the original one can put up some decent data to about 300MHz. The V2Plus4 is certainly one option to experiment above that. Personally, I have not used mine since I picked up the LiteVNA. Personally, I use a PC to control my lab which includes these low cost VNAs. While I no longer update the software for the original NanoVNA, I do continue to develop for the V2Plus4 and LiteVNA. You can find that software here:https://github.com/joeqsmith/Solver32-LiteVNA-V2Plus4If you are interested in seeing how they perform, I have created a few videos showing them with my software. Of course, with low cost we have square wave drive, low dynamic range, lack of features like bias-Ts and attenuators. Video below talks about the square wave drive.

author: graybeard
author_rank: Frequent Contributor
timestamp: August 13, 2022, 01:14:41 am
content: I have both ananovna-fand asva1015x.The sva1015x works well from 10MHz to 1.5 GHz. If i am working in that range it is the one I use. I especially like the log frequency sweep feature and slightly greater dynamic range. The interface is much nicer on the Siglent. It is also faster.However the nanovna-f works far better at lower frequencies. The price is much better too.

author: nctnico
author_rank: Super Contributor
timestamp: August 13, 2022, 08:39:10 am
content: Quote from: graybeard on August 13, 2022, 01:14:41 amAny idea about how the LibreVNA would perform? This looks like a very nice kit for the money.

author: tomud
author_rank: Regular Contributor
timestamp: August 13, 2022, 08:56:38 am
content: Quote from: nctnico on August 13, 2022, 08:39:10 amIt works very well and as I wrote when someone wants a good VNA for little money - this is probably one of the better options. Better than SVA1000X (as soon as we consider using it as a VNA). The SVA1000X has the advantage that the VNA is only one of the functions, unfortunately the poor dynamics of the VNA is a limitation in the case of measurements of filters with higher attenuation.

author: nctnico
author_rank: Super Contributor
timestamp: August 13, 2022, 09:17:17 am
content: Thanks. Can you comment on the lowest frequency the LibreVNA is useful at? The purpose I have in mind right now is looking at PDN (power distribution network) and measuring combinations of decoupling capacitors. Measurements go from sub 1MHz to several hundred MHz (close to 1GHz). I have two VNAs; one goes from 10Hz to 300MHz and the other from 5MHz to 4GHz. There is overlap but for some measurements it sucks needing two instruments.

author: tomud
author_rank: Regular Contributor
timestamp: August 13, 2022, 09:46:38 am
content: @nctnicoI had libreVNA borrowed from a friend and unfortunately I did not test below 3.5MHz, I was basically testing in terms of ham bands. However, I have not heard any opinions that it works beyond the declared specification.Here is a quote about the lower frequencies:QuotePersonally, I was supposed to buy libreVNA ... unfortunately the pandemic and the crisis on the electronic components market hit my finances quite hard and at the moment I am forced to give up all purchases of measuring equipment for hobby applications

author: bd139
author_rank: Super Contributor
timestamp: August 13, 2022, 09:54:53 am
content: I would define what measurements that you need to make carefully before buying one. Write down use cases, examples and test criteria.The existing DSA815-TG may be adequate if you add a directional coupler to it.

author: TopQuark
author_rank: Frequent Contributor
timestamp: August 14, 2022, 08:18:29 am
content: I have the nanoVNA V2 plus, the SVA1032X and the LibreVNA.I'd recommend the LibreVNA (full 2 port S params), but the nanoVNA V3 (aka VNA6000) is apparently just around the corner, so I would wait and see how that thing performs if you only need to measure S11 and S21 without flipping the DUT manually.I'll be reviewing the LibreVNA in a couple of weeks, but the TLDR is:- Software is not very polished (features are a bit hidden, may freeze up after a few hours of continuous use for some users), but has some advanced features found only in VNAs many times more expensive (TRL cal, time gating, 2x thru de-embedding etc.)- Hardware can get hot and readings may drift, but not a problem if you stick a heatsink (optionally a fan) on it.- 6GHz or even higher if using harmonics, giving good time domain resolution for the price.- Full 2-port (measures S11, S21, S22, S12)- I think it is the best value for money in the low cost VNA market right now, open source everything is a big plus.The SVA1032X IMO is primarily a SA with a VNA tacked on it. The features and usability have improved over time, but is not nearly as powerful as the LibreVNA in terms of being a VNA (T/R vs full two port, advanced de-embedding etc. etc.) . I rarely use the SVA1032X as a VNA after I got my LibreVNA.Quote from: nctnico on August 13, 2022, 09:17:17 amThe LibreVNA is designed for 10MHz and up IIRC, but is usable down to 100kHz in my experience (and I do use it down that low), though the S21 dynamic range is only around 40-50 dB from 100k to 1M, not the 90dB dynamic range higher up in frequency.

author: joeqsmith
author_rank: Super Contributor
timestamp: August 14, 2022, 05:28:42 pm
content: Quote from: bd139 on August 13, 2022, 09:54:53 amAgree. You could end up wasting money that could have been put towards something that actually met your needs. That's the advantage of the NanoVNA. At $50, we are not talking about a big investment. If you are just starting with VNAs, the small investment in your education would be a wise choice, IMO.I have a few of these low cost VNAs now and besides the lack of peripherals, low dynamic range and squarewave drive (pretty much what we would expect), the main problems I have run into have been firmware. I have an H4 I wouldn't give away because the firmware was never stable enough to use it.QuoteI'm a little disappointed to read TopQuarks post above about the LibreVNA. It's been available for some time now and I would expect it to be very stable. We had discussed the lack of documentation which would allow a third party to create software for the LibreVNA in another thread.https://www.eevblog.com/forum/rf-microwave/clone-85033e-vna-cal-kit-measured-against-pico-cal-kit-using-librevna/It's been mentioned that you can write scripts to control their software but if that's not stable to begin with... Then there's that whole heat sink deal.

author: tomud
author_rank: Regular Contributor
timestamp: August 14, 2022, 06:26:01 pm
content: @joeqsmithIt must be remembered that libreVNA is still budget equipment with a good price / performance ratio. Haves some flaws but at this price they are forgivable. Let's say this, my set of cables and calibrators costs a lot more than libreVNA.However, poor documentation is unfortunately a feature of probably all open source projects. From my practice, whenever I wanted to change something into open source, it required many hours of source code analysis...I also bought NanoVNA once, but more out of curiosity. The offered price is ok. However, if someone wants to measure filters up to 1GHz, it's a pity to spend even $50. IMHO it is better to collect some money and buy something that will work better in these applications (I keep talking about equipment to buy at a low price compared to a professional VNA).Personally, I mainly use nanoVNA in the field to tune HF antennas. Currently, if I had to buy my first VNA, I would start with nanoVNA V2 or better.

author: joeqsmith
author_rank: Super Contributor
timestamp: August 14, 2022, 07:13:57 pm
content: Quote from: tomud on August 14, 2022, 06:26:01 pmExactly my point. If you know what you need, buy tools that fit those needs. If you don't know what you need, start with the cheapest thing out there to at least learn something before you start making poor choices. I'm not in a position where $50 poses a significant financial burden for my family. In the video above, you can see some of my old test equipment for my hobby use. Like you, the costs of what you see far exceed the total amount I have spent on these low cost VNAs. That was hardly the point but rather the goal was to provide an example to a beginner of where these low cost VNAs may fall short.

author: tomud
author_rank: Regular Contributor
timestamp: August 14, 2022, 07:57:05 pm
content: @joeqsmithIt's not even about money anymore, the price difference between nanoVNA is not that big. However, one gets a bit better dynamics and a wider frequency range.I used to buy a lot of different equipment myself, but suddenly I ran out of space in my small workshop. I ended up giving these devices to my friends for free because I would have wasted more time selling on eBay etc than the hardware was worth. I think that if someone already has a spectrum analyzer with a tracking generator, they already have some knowledge of how to use such equipment so as not to damage it.

author: tautech
author_rank: Super Contributor
timestamp: August 14, 2022, 08:43:27 pm
content: Any serious antenna work rules these cheap devices out.Sure in a lot of the world 315 MHz is available for telemetry but in many other places it's reserved for other needs and 433 MHz used instead which is getting past where even the proponents of these devices ascertain is beyond their accuracy capabilities without even venturing into the popular 800 -900 MHz bands.But then of course there are the LF Ham bands which do fall within cheap instrument capability.

author: joeqsmith
author_rank: Super Contributor
timestamp: August 14, 2022, 09:08:09 pm
content: Quote from: tautech on August 14, 2022, 08:43:27 pmI think we paid about $130 for the LiteVNA which I consider cheap. I soldered up a couple of pork and bean cans and swept the antenna with the Lite.https://www.eevblog.com/forum/rf-microwave/nanovna-custom-software/msg4175104/#msg4175104I think this was tuned around 2.6G or so. Data was collected using this software:https://github.com/joeqsmith/Solver32-LiteVNA-V2Plus4

author: joeqsmith
author_rank: Super Contributor
timestamp: August 14, 2022, 09:11:37 pm
content: Quote from: tomud on August 14, 2022, 07:57:05 pmI also gave up selling on eBay years ago. It goes to the recycle bins or I give it away. My home labs becoming a bit of a functional museum.

author: bd139
author_rank: Super Contributor
timestamp: August 14, 2022, 09:30:24 pm
content: 700 items sold here including at least two NanoVNAs. Gotta eat

author: rf-loop
author_rank: Super Contributor
timestamp: August 15, 2022, 10:34:09 am
content: Quote from: graybeard on August 13, 2022, 01:14:41 amImho, that model (genuine Deepelec, not a copy ) is a pretty good machine (in its price range). Well done. When I lived in China, I bought two of them directly from Deepelec official store, version 3.1. I brought them with me from there. Of course I also left some devices in China so I don't have to get it again later. Sure, it's much better than the old Nano V2. The Nano V2plus4 is a bit different and better in terms of dynamics, although in terms of manufacturing quality it is almost at the poor level, when they don't even know or care how to attach the RF connectors correctly. But it worked out with a little rework. On the other hand, Deepelc's F is manufactured as a completely decent well finished product, unlike many cheap devices in China, which are often made like with bare feet on the garage floor.

author: spacehen
author_rank: Contributor
timestamp: August 23, 2022, 12:34:38 pm
content: Quote from: graybeard on August 13, 2022, 01:14:41 amI've watched some of your youtube videos on the sva1015x Chris, some great information. My one concern with the sva1015x is the fixed 0dbm output power for the VNA. Is this really something to be concerned about? I assume I can just add an attenuator to the input of the DUT? Just a bit annoying I guess when you want to measure the 1db compression point for an amplifier.LibreVNA also looks like a neat product

author: joeqsmith
author_rank: Super Contributor
timestamp: August 23, 2022, 03:48:05 pm
content: The cost of good step attenuators, bias-Ts, blocks, cables, adapters ..... are all something to consider.I did see a post about an improved version of the Lite being available now. I have no idea how well it actually performs but may be worth looking into.https://groups.io/g/liteVNA/topics

author: tautech
author_rank: Super Contributor
timestamp: August 23, 2022, 04:46:45 pm
content: SpacehenBoth TG power level and Port 1 Stimulus level are user adjustable from -20 to 0dB.This info is in the datasheet.

author: nctnico
author_rank: Super Contributor
timestamp: August 23, 2022, 04:48:24 pm
content: Quote from: spacehen on August 23, 2022, 12:34:38 pmWhy not try that one first? From what I've read so far in this thread and other information, it seems to be the best option in your budget range.

author: joeqsmith
author_rank: Super Contributor
timestamp: August 23, 2022, 05:01:08 pm
content: Quote from: nctnico on August 23, 2022, 04:48:24 pmCost is about $600. Another member had posted about the software not being stable and hanging. I assume you own one or you would not be recommending it. Are you seeing similar problems with yours hanging and could maybe provide some additional insight?

author: nctnico
author_rank: Super Contributor
timestamp: August 23, 2022, 05:20:47 pm
content: Quote from: joeqsmith on August 23, 2022, 05:01:08 pmI don't own one but would like to try one for sure. For me it would replace two seperate pieces of equipment and add several capabilities. From where I stand it look likes it has the best bang per buck. Software hanging can have all kinds of causes like a dodgy computer or bad USB ports. The software is also updated regulary so maybe the problems have been fixed already. No reason to discard it off the bat. That is why I wrote: try that one first!

author: spacehen
author_rank: Contributor
timestamp: August 23, 2022, 05:34:59 pm
content: Quote from: nctnico on August 23, 2022, 04:48:24 pmI am definitely interested in purchasing a LibreVNA, I've received some good feedback by some users of the product. By the way I was also looking at several other low cost USB based VNA's too such as the miniVNAhttp://miniradiosolutions.com/54-2/and the pocketVNAhttps://pocketvna.com/.You see the only concern I have with the LibreVNA is that it seems more like a "hobby" project (it also has issues such as crashing, overheating apparently), i.e not backed by a professional test equipment brand name and I am looking for a professional tool to add to my bench (I understand this is difficult at a low price point). I could of course be completely naive here and I've heard that the LibreVNA performs on the same level if not better than the SVA1015X from Siglent but most of the comments here are leaning towards the LibreVNA.Will I be able to measure the input impedance of a simple quarterwave antenna with the LibreVNA for example?Also are there any good reviews for this product (LibreVNA)?

author: nctnico
author_rank: Super Contributor
timestamp: August 23, 2022, 05:55:47 pm
content: I suspect the LibreVNA has no problem measuring your antenna; that is not a super difficult task for any VNA. Most of the differences are in useability.If you want a professional tool, then look on the used market. Recently I bought a JDSU (Viavi) 745A that is a spectrum analyser and VNA in one but has a seperate VNA and spectrum analyser modules. Viavi may not be well known but this is a huge telecom test equipment company.

author: joeqsmith
author_rank: Super Contributor
timestamp: August 23, 2022, 06:17:39 pm
content: I watched all the reviews I could find for the LibreVNA early on. All of them that I saw were your typical unboxing 5 star reviews. I never came across one were the reviewer would lead me to think they knew anything more than how to use a knife to open the box. Nothing against the product itself.Quote from: nctnico on August 23, 2022, 05:55:47 pmI agree, which is why my home lab looks like a museum. I would also add that if you go with used, consider making the sale contingent on having the VNA sent to the manufacture for a full inspection. Maybe the seller pays to have it returned if their are problems, maybe share the costs of repairs. Keeping in mind that these shipping/checkout/repair costs may far exceed the price of these low cost VNAs. Which is why I suggest you make sure you understand what you need before buying anything.

author: tomud
author_rank: Regular Contributor
timestamp: August 23, 2022, 07:30:14 pm
content: LibreVNA, as I have probably mentioned, is not an ideal product.However, at this price point, it's hard to find any good VNAs. If you only care about antennas, you can easily try the cheaper LiteVNA recommended here. If you are thinking about something more and need more dynamics (e.g. filter measurements) I would choose LibreVNA.The Siglent SVA is a nice product, but the VNA as I wrote is just an addition to the spectrum analyzer and does not have great parameters.Personally, I bought a Siglenta SSA3021X Plus without even thinking about the VNA, it turned out that I can easily convert it to SVA1032X by changing the firmware - so at this price I cannot say a bad word about this equipment.The sad truth is that you have to pay a lot of money for a good VNA (even a used one).I think a bit about the Siglet SNA5000 myself, but I will wait for more opinions about this equipment. Probably at a similar price I will look for other solutions in the future (although I am afraid of buying expensive used equipment online - it's easy to be deceived and buy faulty equipment). I have already bought a damaged HP spectrum analyzer (it was supposed to be operational), after thorough tests it turned out to be damaged. On the other hand, the cost of parts on e-bay is so high that it doesn't pay to repair it. Maybe someday I will find a similar one at a low price to take apart and I will be able to run itSo if you only care about antennas, I think you can trustjoeqsmith'sopinion and see how LiteVNA works (especially since it's a small expense). Watching Brymen 869s multimeter tests on Joeqsmith Youtube channel I decided to buy this meter and I am very pleased. So I think you can rely on his opinion on LiteVNA.

author: joeqsmith
author_rank: Super Contributor
timestamp: August 23, 2022, 07:52:31 pm
content: OWO had talked about a new product with wider dynamic range. It appears they released it but the cost is $800. Again, I have no knowledge of the product. It appears very similar to the V2Plus4. Maybe following the Lite's lead to reach the 6GHz. May be interesting to see some sort of shootout of all the sub $1000 VNAs from someone that actually knows what a VNA is. Maybe we could talk Brian Walker into it! May make for a good sales pitch for Copper Mountain.https://nanorfe.com/vna6000.html

author: joeqsmith
author_rank: Super Contributor
timestamp: August 23, 2022, 08:28:48 pm
content: Quote from: tomud on August 23, 2022, 07:30:14 pmDon't say that!!It just seemed they were in a similar position as a friend of mine wanting to buy their first VNA without knowing the first thing about it. That's what sent medown the NanoVNA path.I only suggest these low cost VNAs are a great educational tool because of the low risk. I would still suggest if someone wanted to experiment below 300MHz, maybe learn about PDN measurements, work with very narrow band devices like crystal filters, the original NanoVNA makes a very good choice. Worse case, your only out $50. Your not going to ship an HP8753E for that.***lol. Forgot to finish my sentence.

author: nctnico
author_rank: Super Contributor
timestamp: August 23, 2022, 08:44:56 pm
content: Quote from: joeqsmith on August 23, 2022, 06:17:39 pmI think that is a typical problem with not so professional products in this price range. It is too expensive to take a chance on and very few people buy it just for a review. Fortunately a -to me- local webshop ( Eleshop.nl ) also carries the LibreVNA so it is relatively easy for me to get one to try if/when I'm interested in buying one. If I don't like it, I can return it without hassle.

author: joeqsmith
author_rank: Super Contributor
timestamp: August 23, 2022, 09:30:17 pm
content: Quote from: nctnico on August 23, 2022, 08:44:56 pmIf you end up getting a loaner, consider making a review for it. I'm surprised for the LibreVNA that they didn't consider sending them out for a reviews to stir up the interest.

author: joeqsmith
author_rank: Super Contributor
timestamp: August 27, 2022, 05:54:42 pm
content: Today I was reminded why you may want to consider a very low cost VNA like the NanoVNA to start out with. Some time ago I produced a video attempting to show hams how not to blow up their NanoVNAs after seeing so many posts from them about how they damaged theirs. Today I noticed this gem of a post. They use a standard to drain down their antenna before connecting to the VNA. Granted it's a $50 VNA and the standards (we use the term loosely) were included at that price. IMO that is not a good excuse for such a poor practice.

author: Marcel G
author_rank: Contributor
timestamp: August 27, 2022, 06:10:28 pm
content: Tomud,Buy a real VNA recently bought a Siglent SVA to see if it is something.The Spectrum Analyzer function is nice but the VNA is outright toy.I may also have an Agilent E5062A for sale, but that is in a different price range than, for example the SVA.

author: tomud
author_rank: Regular Contributor
timestamp: August 27, 2022, 10:59:28 pm
content: Quote from: Marcel G on August 27, 2022, 06:10:28 pmI mention this all the time that in SVA the VNA option is only a limited addition to the spectrum analyzer...Therefore, I did not buy an SVA but an SSA Plus, and since it turned out that it is possible to convert SSA Plus to SVA, I took advantage of it.However, when it comes to purchasing a VNA, I'll probably be looking for something in the future, but at least up to 6GHz.

author: Marcel G
author_rank: Contributor
timestamp: August 28, 2022, 07:52:17 am
content: I did not buy an SVA but an SSA Plus, and since it turned out that it is possible to convert SSA Plus to SVA, I took advantage of it.Sorry it,s a converted SSA Plus, a worthless device and a waste of money.Once you have worked with real VNA you have forgotten ALL the solutions suggested here. (Nanovna, Libre, VNWA, LiteVNA, SVA, SSA etc etc).My advice is save enough money and buy a real VNA.

author: tautech
author_rank: Super Contributor
timestamp: August 28, 2022, 07:59:10 am
content: Quote from: Marcel G on August 27, 2022, 06:10:28 pmWhich model as in the SVA range there are 3 different lots of specs.What did you need the single port VNA to do ?They can only do S11 and S21 measurement with the single active port so when you need reverse the stimulus for S12 and S22 measurements so the DUT must be flipped instead.However SNA5000A VNA's with 2 or 4 active ports are an entirely different beast .

author: Marcel G
author_rank: Contributor
timestamp: August 28, 2022, 08:08:24 am
content: Hi Tautech, Would like to try out an SNA5000A or read a good (review) test, but unfortunately they are still somewhere.Somewhere on this site there is someone who owns a decent device but the test he has done mean nothing in practice.

author: tautech
author_rank: Super Contributor
timestamp: August 28, 2022, 08:28:07 am
content: Quote from: Marcel G on August 28, 2022, 08:08:24 amWe have a SNA5005A, the 4 port 4.5 GHz model which as yet I haven't done a lot with yet however I do want to get it to my buddy hendorog whom is a VNA whizz kid for some more complex tests and comparison against his HP VNA's.There's a thread here I started about them:https://www.eevblog.com/forum/testgear/siglent-sna5000x-two-and-four-port-vnas-coming/Then I realize I'm a bit slack as we had it on display at NZ EMEX bidirectionally sweeping one of hendorog's filters and I never grabbed screenshots !If you want to see something from it do ask and we'll take it to the thread.

author: tomud
author_rank: Regular Contributor
timestamp: August 28, 2022, 10:14:29 am
content: Quote from: Marcel G on August 28, 2022, 07:52:17 amI have access to a good VNA (Keysight N5242B), but sorry I'm not going to spend that much money on hobby equipmentAnother thing is just not me asking in this thread what VNA to buyMaybe in the future I will buy an SNA5000 or some other VNA, but at the moment I do not plan such a purchase... The mentioned E5062A has too little bandwidth for me. I need a minimum of 6GHz and the dynamics is preferably 125dB

author: nctnico
author_rank: Super Contributor
timestamp: August 28, 2022, 10:52:50 am
content: Quote from: Marcel G on August 28, 2022, 07:52:17 amI don't doubt that at all but when I looked for a VNA last year, I noticed that a real VNA which has a decent amount of life left (so with at least a TFT screen) sets you back quite a lot of money. Like 4k to 6k euro; even the broken ones go for serious amounts of money (ballpark 3k euro).

author: Marcel G
author_rank: Contributor
timestamp: August 28, 2022, 01:15:26 pm
content: Tomud,I have access to a good VNA (Keysight N5242B), but sorry I'm not going to spend that much money on hobby equipment.Then you know exactly the difference if you don,t have the money for it then it stops and you can,t make demands either.Tautech,Please do an extensive test like he has tested the SVA1015 and would also like to see the speed at different bandwidths (full span) and trace noise.The sales story of Siglent on Youtube could not convince me enough to buy the device.I called the importer (Eleshop) here in the Netherlands for a test, but they don,t have one in stock.Regards,Marcel

author: joeqsmith
author_rank: Super Contributor
timestamp: August 28, 2022, 03:20:55 pm
content: Quote from: tomud on August 28, 2022, 10:14:29 amIf you are using the N5242B for work, you may not be happy with the low cost VNAs. The 125bB would certainly be a deal breaker.Quote from: nctnico on August 28, 2022, 10:52:50 amI was looking for something with TFT, Ethernet, 4-receiver, 1kHz to 3GHz. There was a person trying to sell me a turn key PNA with faster CPU/cal standards/cables for I think 13 USD. Way over my budget. I watched them post it and eventually dropped the price to I think under 8. A very good deal IMO assuming it all worked.

author: tomud
author_rank: Regular Contributor
timestamp: August 28, 2022, 06:29:55 pm
content: Quote from: Marcel G on August 28, 2022, 01:15:26 pmFor hobby applications, I have to compromise and I am aware that I will not buy the perfect VNA. Therefore, I tried to recommend a few devices, maybe not perfect, but with a good price / quality ratio. Especially when someone does not have great expectations. Many hobbyists are often satisfied with nanoVNA (e.g. tuning antennas in HF bands). I have nanoVNA myself and its capabilities are sufficient for me to tune the antenna working at 7 or 14MHz in the field (it can even handle 144MHz quite well).I am also able to give up some functionalities, because most often I need a VNA for duplexer tuning - nowadays the corac would be more useful in the 5GHz band...For such applications, I can safely look for cheaper solutions (not laboratory equipment).For example, the SNA5000 looks interesting, because it has an attractive price in relation to used equipment (which is not known in what condition it will be possible to buy it). On the other hand, VNA cannot be thoroughly checked when purchasing and any damage or problems may only come out after a long time, so you will not benefit from the protection of auction sites or paypal.Apart from the fact that most of the prices on ebay are crazy and the equipment is not worth that much. Such an example of the HP8712 which costs in the range of $1500-2000 on ebay. However, in Poland, you can buy one on flea markets for $260. Recently I tried to sell a frequency meter up to 40GHz (Anritsu MF2414B option 03) for half the price from ebay and nobody wants to buy it for that much

author: tautech
author_rank: Super Contributor
timestamp: August 29, 2022, 10:41:39 pm
content: Quote from: Marcel G on August 28, 2022, 01:15:26 pmAs it happens Shahriar has just released Pt1 of his SNA5000A review where he pushes some features to their limits, explores other functionality, engage with Siglent for some improvements and does a teardown.

author: Marcel G
author_rank: Contributor
timestamp: August 30, 2022, 09:22:37 am
content: Tautech,The first thing I noticed was the slow sweep speed hopefully Siglent improves on this.My 12 year old E5062A is a lot faster.

author: tomud
author_rank: Regular Contributor
timestamp: August 30, 2022, 10:12:49 am
content: Quote from: Marcel G on August 30, 2022, 09:22:37 amThe equivalent to the E5062A is the SNA5002A (although the SNA has a band up to 4.5GHz) which costs 6600 Euro net.E5062A - Measurement speed: 35 ms (2-port cal, 30 kHz BW, 1 sweep, 201 points, correction off)SNA5012A - Measurement speed (100 kHz - 8.5 GHz, 10 kHz BW, 201 points) Uncorrected 33 ms, 2-port cal 66 msI don't know what Agilent means by "correction off", but looking at 10kHz BW at SNA and 30kHz at Agilent - SNA seems to be faster after all.

author: tautech
author_rank: Super Contributor
timestamp: August 30, 2022, 10:21:43 am
content: Quote from: Marcel G on August 30, 2022, 09:22:37 amDoes speed = accuracy ?Also speed is relative to SpanandPoints which for SNA can be 10k.We await Pt 2 from TSP.

author: switchabl
author_rank: Frequent Contributor
timestamp: August 30, 2022, 10:24:31 am
content: Quote from: Marcel G on August 30, 2022, 09:22:37 amAccording to the datasheet it shouldn't be. Are you comparing it at the same settings? I think Shahriar had it at something like 500 Hz IFBW, 500 points. That is going to slow it down a lot. The fact that he was using the remote interface may not help either.EDIT: This is assuming we are talking about the SNA5000A video here and not about the SVA.

author: rplabs
author_rank: Contributor
timestamp: August 30, 2022, 12:52:39 pm
content: Hello all,I wanted to share my thoughts here since I am in search for a new VNA also.I own a NanoVNA V2plus4 for a long time and it was OK for my amateur radio stuff I do for up to 4GHz but now I need something in the range of 8-12GHz. Solver32 program also helps a lot to increase the usability of the small NanoVNA.As for used VNAs... I am looking on eBay for more than 2 months and prices are crazy for any VNA. Even if it is 20 years old and shows errors or is not working prices in EU are at least 3K EUR.Same applies for old SNAs on eBay, 2K EUR and they are not tested and are missing the detector heads. Buying the detector heads will bring the price same as a VNA.On the good side I saw on LibreVNA groups.io list they work to combine multiple VNAs to create something like a cluster. Not clear if this can be used to increase the max frequency of 6GHz or it just does different measurements where one unit cannot do it.

author: tomud
author_rank: Regular Contributor
timestamp: August 30, 2022, 01:05:23 pm
content: Quote from: rplabs on August 30, 2022, 12:52:39 pmupss it will be painful financially...Apparently, SNA5000 variants will appear at frequencies higher than 8.5GHz - but here the price will probably not be low. The same applies to the prices of calibrators and cables.Unfortunately, these are already large amounts of money to spendSometimes I build radars on 24GHz myself and a VNA would be useful, but I do not even think about it because it is outside my private budget.However, as for the prices and condition of equipment from ebay etc you are right. (it often looks like equipment found in a dumpster)You can try to buy the HP 8510C + 8516A + 83621A, but it is not the latest equipment and you need a lot of space in the workshop...

author: joeqsmith
author_rank: Super Contributor
timestamp: August 31, 2022, 03:30:37 am
content: Quote from: rplabs on August 30, 2022, 12:52:39 pmThey changed the LiteVNA's firmware to use harmonics and cap it at 9.3, at least with the version I currently have installed. I've thought about putting together an up/down converter for it with some software support. I have some support today and demo'ed the NanoVNA I think above 2GHz. Maybe something to consider.

author: jhov
author_rank: Newbie
timestamp: August 31, 2022, 05:16:58 am
content: I'm not sure how it compares to your other options, but a Pluto Plus SDR with albfers SATSAGEN software might be worth looking into. His latest version added VNA capability using an RF bridge.https://www.albfer.com/en/2022/05/29/satsagen-v-0-7-1-4/#content

author: switchabl
author_rank: Frequent Contributor
timestamp: August 31, 2022, 08:55:27 am
content: Quote from: jhov on August 31, 2022, 05:16:58 amI have the older revision of the Pluto, so I can't try this out. But the isolation between TX and RX is pretty bad. I expect the dynamic range to be very limited. You may be able to improve this somewhat by reducing the source power and adding some external gain. But in the end, it wasn't exactly built as a VNA.

author: tomud
author_rank: Regular Contributor
timestamp: August 31, 2022, 09:58:11 am
content: Pluto was designed as a low-cost SDR for educational purposes. You can attach the coupler, but as it was said, I would not expect miracles.Especially that for the price of a Pluto and a coupler with reasonable parameters, you can probably buy any budget VNA - which will be more convenient.@joeqsmithYes, you can think of harmonics (even Keysight FieldFox works that way). However, at frequencies such as 8GHz and above, everything becomes more complicated and there are no simple solutions. It can be seen even from all budget VNAs what parameters they reach at the end of the bandwidth in which I work (whether it will be libreVNA or others).Even if a project of such a VNA is created and has acceptable parameters, it will not be cheap. There is nothing to cheat here, targeting frequencies of the order of 10GHz will not be cheap...At the moment, only the older VNAs remain - the question is to find one that is reasonably priced and undamaged (which won't be easy). Anyway, when buying old measuring equipment, you have to reckon with the fact that sooner or later you will have to repair something, replace the capacitors or something else. If I had more room in the workshop I would try to buy the HP 8510C, this is probably the only reasonable option in terms of cost and repairability.

author: joeqsmith
author_rank: Super Contributor
timestamp: August 31, 2022, 01:09:28 pm
content: For up/down conversion, I wasn't thinking harmonics but yes, there's a higher cost it seems the faster you go. This seems to hold true with with my bikes as well. The quicker they are, the more they cost.I was very surprised when they released the LiteVNA that supported 6GHz and only cost $130 USD. The fact it works at all is amazing. I'm looking forward to seeing where they go next.

author: rplabs
author_rank: Contributor
timestamp: September 01, 2022, 09:30:07 am
content: Quote from: tomud on August 30, 2022, 01:05:23 pmYes, that's why I search eBay and other local sites for more than 2 months without any hope now.Looks like it is cheaper to buy it from US and pay customs and shipping to EU.Quote from: tomud on August 30, 2022, 01:05:23 pmI saw them and was thinking about it but only broken ones are cheap. The ones that power on and show something on display are almost the same as a not tested but powering on Rohde & Schwarz ZVM. Also the shipping costs will be probably high for that if it is not in a normal driving distance to the seller for pick up.I'm not in a hurry. It is just for my amateur radio hobby so I can wait for a good deal.

author: rplabs
author_rank: Contributor
timestamp: September 01, 2022, 09:38:01 am
content: Quote from: joeqsmith on August 31, 2022, 03:30:37 amInteresting but I didn't see this mentioned anywhere. I saw only that LiteVNA upper frequency is 6.3GHz and reports that the noise floor is higher than NanoVNA V2plus4.Do you have a link with more details about 9.3GHz firmware running on LiteVNA?9GHz would be OK for me now to test some filters, isolators and mixers for the amateur DSN project that I want to build now.

author: rplabs
author_rank: Contributor
timestamp: September 01, 2022, 09:46:59 am
content: Quote from: tomud on August 31, 2022, 09:58:11 amHmm... I can only see in EU only this one from a seller in Italy and it costs 24K Euro.https://www.ebay.at/itm/304194390464For the same price you get the R&S ZVK up to 40GHz.https://www.ebay.at/itm/324827992024I am sure the ZVK will use less power also and also less space and it is a more modern unit.

author: tomud
author_rank: Regular Contributor
timestamp: September 01, 2022, 10:51:05 am
content: Quote from: rplabs on September 01, 2022, 09:30:07 amUnfortunately, I also have such a problem and to be honest I have been looking for a decent VNA for a home workshop for many years. Unfortunately, when something interesting appears on the market, it is quickly bought by people who professionally trade equipment, and then sell it at very high pricesUnfortunately, to buy something at a good price, you need a lot of free time to follow the auction (unfortunately I do not have this time), when something appears at a good price, unfortunately it disappears immediately.24k euro for 8510C IMHO is a crazy price. If I had a larger workshop, I would prefer to buy a few cheap damaged ones and assemble them into one functional measuring instrument. Even with a lot of bad luck, it would be cheaper anyway.There is even an attempt to use the HP 8515A module on the Polish forum and do the rest yourself. But I don't know how this attempt ended (Unfortunately, the topic is in Polish:http://mikrofale.iq24.pl/default.asp?grupa=160341&temat=423430)Maybe it would be a good idea to look for hams who have such measuring equipment at home and talk to them about the chances of repairing such a device.I am slowly starting to think about the Siglent SNA5000. I'm still waiting for independent reviews and most likely, if the reviews are good, I will buy up to 8.5GHz. Yes, I would like something more, but you have to think realistically ... and at the moment the most I miss the possibility of measuring in the 5.7GHz band.

author: nctnico
author_rank: Super Contributor
timestamp: September 01, 2022, 11:24:58 am
content: The question is: do you really need a network analyser? IOW: do you need phase information for your measurements? A low cost option would be to use a spectrum analyser + sweep generator. This will be slow but at least can give you some graphs (amplitude and VSWR -if you have a directional coupler-).

author: rplabs
author_rank: Contributor
timestamp: September 01, 2022, 12:29:01 pm
content: Quote from: nctnico on September 01, 2022, 11:24:58 amYes, you are right that for this task a spectrum analyzer + sweep generator will work but... I have the SA and I am looking for a sweep generator to cover also 8-12GHz and those are also not cheap.I contacted a few sellers on ebay in EU and they were selling "good" units but in fact from pictures I could see errors. When I asked about errors they were saying just "no issue, it works. Buy it and test it by yourself and you will see it is OK." Right, so I need to pay a few K Euro and test it to see if it is really broken or not? Not to say that this is 20+ years old equipment which can fail anytime...

author: joeqsmith
author_rank: Super Contributor
timestamp: September 01, 2022, 12:40:58 pm
content: Quote from: rplabs on September 01, 2022, 09:38:01 amhttps://groups.io/g/liteVNA/topic/first_tests_above_6_3ghz/87993520?p=Created%2C%2C%2C20%2C1%2C20%2C0%3A%3Arecentpostdate%2Fsticky%2C%2C%2C20%2C2%2C20%2C87993520%2Cprevid%253D1643508180797191034%2Cnextid%253D1640273623127907015&next=1***The software I wrote doesn't limit the frequency the VNA uses. If for example the user enters 1THz for the start frequency, the software assumes you are smart enough to know what you are doing and will gladly write the data to the VNA.I did attempt a few of my own experiments using harmonics but it's not something I am really setup for.

author: rplabs
author_rank: Contributor
timestamp: September 01, 2022, 01:24:52 pm
content: Quote from: joeqsmith on September 01, 2022, 12:40:58 pmInteresting read but I noticed from the screenshots posted in the thread that performance is not quite good after 7.5~8GHz in my opinion but it is a start. I am not sure if this extended range can be improved. Seems like a hardware limitation.Quote from: joeqsmith on September 01, 2022, 12:40:58 pmYour software is amazing. Many thanks for publishing it, I appreciate it!

author: joeqsmith
author_rank: Super Contributor
timestamp: September 01, 2022, 01:47:33 pm
content: At least with the LiteVNA, there were/are problems with the USB power supply. Same for the V2Plus4. This can have a dramatic effect on the VNAs performance. I suspect they capped the firmware I have at 9GHz as there was no useful information after this.Quote from: rplabs on September 01, 2022, 01:24:52 pmGlad to hear.

author: LogicalDave
author_rank: Regular Contributor
timestamp: September 09, 2023, 01:28:58 am
content: QuoteI know this comment is more than a year old, but would you be willing to expand on your statement?Each of these devices has a price point and is designed to meet certain needs. What would be most helpful to people reading these threads is understanding the capabilities and limitations of each VNA *for specific tasks*. For example, when sweeping/tuning an 868MHz antenna, characterizing a filter or a discrete component or feed line, tweaking a diplexer, etc., at what point does a user who does not have unlimited funds need to step up from a NanoVNA to a LibreVNA or SVA10xx to a Copper Mountain VNA to a "real VNA"?

author: tautech
author_rank: Super Contributor
timestamp: September 09, 2023, 01:35:11 am
content: Typically, only when you need to fully characterize a device with S11, S21, S12 and S22 measurements.SNA5000A models allow for this by providing bidirectional stimuli.