Comparison Table of Low-Cost VNAs? - Page 1
Forum section: electronics / rf-microwave

author: radiostuff
author_rank: Contributor
timestamp: March 03, 2022, 05:01:07 pm
content: I have a need for a VNAs to test sub-2.4 GHz cables, filters, and antennas. I would prefer that it costs less than $500. I've been searching for an unbiased table of features, software support, and ease of use of the various low-cost VNAs, but have not come across anything useful. There is a monstrous amount of information the NanoVNA Custom Software thread, but I'm not sure there's anything there that answers my question. There are some lists on various websites, but they are all just regurgitation of the marketing material found on the individual product pages. Is there a table of pros/cons of the various VNAs in this segment (NanoVNA, LiteVNA, LibreVNA, Deepace, etc)? As of right now, which product is best for someone who wants to make simple measurements?

author: nctnico
author_rank: Super Contributor
timestamp: March 03, 2022, 06:01:30 pm
content: I'd look at the second hand market too. Especially at cellular analysers that have 2 port analysis functions. Tektronix Netek Y400 with YBT250 and YBA250 modules could be a good option to have better sensitivity and these fit your budget. Although this device doesn't offer vector measurements.

author: radiostuff
author_rank: Contributor
timestamp: March 03, 2022, 06:56:19 pm
content: Are the vector measurements required for phase matching?

author: hwalker
author_rank: Contributor
timestamp: March 04, 2022, 12:54:29 am
content: A scalar network analyzer measures only the magnitude part. A vector network analyzer measures amplitude and phase. The secondhand market name brand network analyzers can be a great deal but ...1. Most don't come with accessories (calibration standards, interconnecting cables, adapters etc.) Purchased separately those items can wind up costing you as much as deal you paid for the secondhand analyzer.2. If you have an oops! moment the repair of a secondhand analyzer is usually not economical. The same oops! moment on a NanoVNA family of devices is either a DIY repair or call it a learning experience and buy another device for less than USD $150.3. Hard to find the same type of user group information and different PC software support for the secondhand brand name network analyzers that you can for the NanoVNA family of devices.I attend a lot of hamfests (pre-COVID) and swap meets. Having a portable VNA on hand like a V2 or LiteVNA has allowed me to cherry pick attenuators, filters, microwave cables, loads and other components. Well worth my purchase.Herb

author: radiostuff
author_rank: Contributor
timestamp: March 04, 2022, 01:19:28 am
content: How do you like the LiteVNA compared to the NanoVNA v2?

author: hwalker
author_rank: Contributor
timestamp: March 04, 2022, 08:17:03 am
content: The LiteVNA takes most of its hardware design from the V2, so measurement results up to ~3.5GHz are about the same. The LiteVNA extends the top end frequency to 6GHz within its specifications and even gives useable results to 8GHZ in the harmonic mode. The following are the points I like most about the LiteVNA over the V2.1. It has a faster processor and more memory which allows it to have up to 1024 display points versus up to 401 display points for the V2. This is on the device itself not from the PC application.2. It has a SanDisk drive for saving screenshots and S1P/S2P files.3. The additional memory allows more features to be added to the LiteVNA which makes it more future proof. The current firmware makes use of the additional memory by adding 4 more trace memory storage locations which are very helpful when comparing and documenting different devices.4. It has a serial interface on-board for adding a wireless connection. This requires the user to buy and install additional components.5. Display brightness control can be set from the "CONFIG" menu.6. It has a real-time clock already installed. The time and date can be set from the "EXPERT" menu and are useful for automatically time-date stamping files saved to the SanDisk drive.7. It has a rudimentary FFT function useful for comparing the magnitude of harmonics if you don't have a specan or scope with FFT on hand.8. It has a battery level display screen display.9. I has a floating-point processor unit which some V2's do not.I'm hanging on to my V2 as a back-up, but after I'm more comfortable with my LiteVNA64 I plan on ordering a second one and then selling my V2. The LiteVNA and LiteVNA64 are $110 and $125, respectively here in the USA (R&L Electronics is the official reseller).Herb

author: cdev
author_rank: Super Contributor
timestamp: March 04, 2022, 12:30:38 pm
content: Is this "Comparison Table of Low Cost VNAs" or is the table in another post??I would love to be able to save screenshots, calibration data, touchstone files, s-parameters, etc. But that would likely require an OS to do it in?$500 is way too much, guys.. You are missing the target if you want to charge that much. For students and many hobbyists, even $100 is too much, honestly. Money is tight these days.I am willing to use my NanoVNA tethered if thats what I need to do to make more detailed measurements.

author: hwalker
author_rank: Contributor
timestamp: March 04, 2022, 02:48:32 pm
content: 1."Is this "Comparison Table of Low Cost VNAs" or is the table in another post??"You didn't miss anything. The original poster asked if a comparison table for low cost VNAs existed. Each of the low cost VNA's have feature sets which are not always documented in their specifications, so it is difficult to put a table together unless you own each VNA or can get a lot of user feedback to create one.2."I would love to be able to save screenshots, calibration data, touchstone files, s-parameters, etc. But that would likely require an OS to do it in?"Some low cost VNA's, such as the LiteVNA, can save screenshots and s1p/s2p files to an on-board micro-SanDisk card for transfer to a PC at a later date. Most of these VNA's store calibration data internally. Depending on the model and firmware used, up to 7 named calibration ranges can be saved and recalled. This is done on the VNA itself and does not require connection to a PC.3."$500 is way too much, guys.. You are missing the target if you want to charge that much. For students and many hobbyists, even $100 is too much, honestly. Money is tight these days."Just 2 years ago you couldn't touch a 3GHz or 6GHz hobbyist grade VNA with an LCD for even $500. A moderately priced antenna analyzer was well over $100 and plenty of hobbyists were purchasing them. In perspective, I consider the NanoVNA-H4/V2/V2+4/LiteVNA to all be bargains, with most costing less than $150. As a student, I would rather purchase one of these devices and get hands-on experience learning about VNAs rather than a couple of textbooks for $150.4.I am willing to use my NanoVNA tethered if thats what I need to do to make more detailed measurements.Once connected to a PC via their USB ports, all of these low cost VNAs allow even more detailed measurements, saving screenshots, saving touchstone files, and performing/saving calibrations with more data points than are available on the device itself.Herb

author: mawyatt
author_rank: Super Contributor
timestamp: March 04, 2022, 02:54:25 pm
content: Quote from: hwalker on March 04, 2022, 08:17:03 amWhat's the difference between the standard LiteVNA and 64 models?Best,

author: hwalker
author_rank: Contributor
timestamp: March 04, 2022, 03:40:19 pm
content: "What's the difference between the standard LiteVNA and 64 models?"The LiteVNA (also referred to as LiteVNA62) is the 2.8" screen model. The LiteVNA64 is the 4" screen model. Other than screen size, the only other difference is battery size and charging circuitry.The extra $15.00 for the 4" model is well worth it.Herb

author: radiostuff
author_rank: Contributor
timestamp: March 05, 2022, 06:25:32 pm
content: @hwalker Do you have any other VNAs that you can provide feedback on?

author: hwalker
author_rank: Contributor
timestamp: March 05, 2022, 09:08:50 pm
content: "... Do you have any other VNAs that you can provide feedback on?"I have owned or used most of the NanoVNA and V2 family of devices, except for the V2+4. My experience is that if you purchase your device from an authorized or reputable reseller, then any of these low cost VNAs will meet the OEM's specifications.Up to ~3.5GHz (V2 series and LiteVNA) these low cost VNAs have a S21 dynamic range of at least 70dB. Above 3.5GHz, the S21 dynamic range is at least 50dB. The dynamic range does not approach that of a commercial VNA (Agilent, Tektronix, R&S) but at a cost of <$150 USD shouldn't be expected to. The calibrated S11 noise floor for these low cost VNAs is generally <-50dB f <3GHz, and <-40dB f >= 3GHz. I've always considered a return loss measurement of at least -30dB to be satisfactory for measuring antenna VSWR, so S11 noise floor <-40dB is more than sufficient for my own measurements.The devices are primarily aimed at students, electronic enthusiasts and amateur radio operators. The devices pretty much hit their mark for that target group. Anyone planning on purchasing one of these low cost VNAs should carefully read the OEM's table of specifications and ensure that they meet or exceed their requirements. Also, check the OEM's on-line presence to see what software is available for the device they are contemplating and how often firmware updates are issued. I've purchased >$500 devices only to later learn that no PC software applications were available, connectivity via USB was poorly documented, and/or no firmware upgrades were issued after the initial release.My occupation was as an EMC test engineer, and I've used several commercial VNAs in the past. I was already familiar with a VNA's operation and the importance of proper SOLT calibration. An antenna analyzer is the only similar experience a lot of first-time users of the low cost VNAs have. An antenna analyzer is basically a plug & play device and a VNA will present a challenge to those users expecting the same plug & play experience. Self-education and hands-on on use are keys to using any piece of test equipment effectively.Herb

author: xmo
author_rank: Regular Contributor
timestamp: March 06, 2022, 12:56:31 am
content: " An antenna analyzer is basically a plug & play device and a VNA will present a challenge to those users expecting the same plug & play experience. Self-education and hands-on on use are keys to using any piece of test equipment effectively."You hit the nail on the head. Someone buying a benchtop instrument for several or more thousand USD probably expects a steep learning curve - and is prepared to invest the time consistent with the cost.The new tools are so affordable that the simply curious may buy one without expecting the complex capabilities.

author: cdev
author_rank: Super Contributor
timestamp: March 06, 2022, 01:29:30 am
content: I welcome the new competition. There is a need for tools like this. You should make a Comparison Table of Low-Cost VNAs, if you are familiar with the specs..An inexpensive tool is particularly useful for students..Thank God that tools like VNAs are no longer under patent..I am watching an excellent series on intellectual property with (australian legal scholar and author (of Information Feudalism). Peter Drahos speaks.. on the Real News Network YouTube channel. Its a seven part series..Its very good discussion on patents and the concerns that exist..

author: cdev
author_rank: Super Contributor
timestamp: March 06, 2022, 01:34:00 am
content: Quote from: xmo on March 06, 2022, 12:56:31 amThose are the people who often figure out new ways to use tools..