Which entry-level VNA is recommended in 2024 (Guide)?

[Songhua]

At the time of writing, in June 2024 we have many entry-level opensource/closesource hardware/software VNA devices.

Correct me if I'm wrong.

For example, NanoVNA V2 (0-3GHz) It's opensource hardware.

NanoVNA V3 (also known as VNA6000) freq range:50kHz - 6GHz, closesource hardware

NanoVNA F-V3 (A clone of NanoVNA V3 but cheaper) freq range: 50 kHz - 6.3 GHz,  closesource hardware

LiteVNA (A clone of NanoVNA V2) freq range: 50 kHz - 6.3 GHz, closesource hardware. It's different from NanoVNA V3(VNA6000) and NanoVNA F-V3. Because LiteVNA uses harmonics to predict received signals from 3GHz to 6GHz which is not accurate.

LibreVNA freq range: 100k-6GHz, opensource hardware claiming to be lab-graded. And it's pricy.

I saw a video doing comparision about NanoVNA V2, NanoVNA F-V3 and LiteVNA



Which wide-range VNA do you suggest?

Appreciate your comments!

[Solder_Junkie]

I recommend the NanoVNA H4 version as it can be configured as a Phase Frequency Analyser by loading alternative firmware. You can swap between the uses by re-loading firmware.

Two instruments in one!

I have a H4, and a TinyPFA, which is a bit extravagant as the H4 can easily do both jobs.

In case you are wondering, this is what a PFA is used for:
https://www.qsl.net/g4aon/gpsdo/

SJ

[ftg]

At the time of writing, in June 2024 we have many entry-level opensource/closesource hardware/software VNA devices.

Correct me if I'm wrong.

LiteVNA (A clone of NanoVNA V2) freq range: 50 kHz - 6.3 GHz, closesource hardware. It's different from NanoVNA V3(VNA6000) and NanoVNA F-V3. Because LiteVNA uses harmonics to predict received signals from 3GHz to 6GHz which is not accurate.
...
Which wide-range VNA do you suggest?

LiteVNA uses 23.5MHz to 6000MHz MAX2870 synth above 100MHz and Si/MS5351 below 100MHz.

So the synth goes properly to 6.3GHz, no harmonic mixing required.
But the mixers, bridges and switches start to degrade in performance when used that high.

As for which one, it depends on your use cases.

I have A clone NanoVNA V1, original NanoVNA V2.2 from NanoRFE and recently got a LiteVNA at the office.

Everyone of them is better than the others at something.

With stock firmwares NanoVNA V1 is the best for measuring narrow High-Q filters like SSB crystal filters.
It has a very fine frequency step and the output is constant due to it having 3x mixers and ADC channels.

V2 has a more coarse frequency step and the internal ECAL, which makes it exceptionally temperature stable causes the output to have an AM modulation, which makes high-Q filters ring.

As said, V2 is very temperature stable and does not drift after it warms up, unlike V1 and LiteVNA.
The official nanorfe made V2's also have very good dynamic range across the specified frequency range, for the price.
So V2 is best of the bunch for repeatable lab measurements.

And LiteVNA goes to 6.3GHz, so it covers all cellular bands and all wifibands outside of 6GHz wifi 6e and 60GHz.
But as some folks have demonstrated here on the forum, it seems to drift with temperature as it warms up.
But if one wants to tinker with 5.8GHz things or check that harmonic filters work up to 6GHz, then LiteVNA is the cheapest choise for that.
Not that it's dynamic range on 6GHz is anywhere near the best.

So, it all depends on your interests and usecases.
This comparison also does not take into account what the devices can do with alternative firmware.

[pdenisowski]

I recommend the NanoVNA H4 version as it can be configured as a Phase Frequency Analyser by loading alternative firmware. You can swap between the uses by re-loading firmware.

So it looks like you can use the TinyPFA like a traditional (analog) vector voltmeter, at least in terms of comparing phases.  Interesting.

[dobsonr741]

@Songhua, why do you need a VNA? That answer should guide which one to choose.

I bought a simplest V2, when I built a QRP kit, and had to measure the inductors I wound, SWR and impedance of antenna. I do not mind the max 150MHz it goes without harmonics. It worked great for HF.

IMO, three are very little use of the 6GHz super specs version, unless you don’t mind spending on i

[Songhua]

This is just a general discussion about VNA for hobbyists.

When you get a VNA, it's better to have a future-proof VNA.

For now I would need VNA for some RF signal and RF antenna test. Freq be around 110MHz, 433MHz, 868MHz, 915MHz, 2.4GHz, and 5.8GHz.

Here we focus on the balance of the budgets and reliabilities of VNA.

Reliabilities includes: technical support, freq range, accuracy and etc.

[ftg]

...
For now I would need VNA for some RF signal and RF antenna test. Freq be around 110MHz, 433MHz, 868MHz, 915MHz, 2.4GHz, and 5.8GHz.
...

For under 300eur LiteVNA is the only one that covers 5.8GHz as far as I know.

LibreVNA and the various Measall and Deepace products are above 600eur most of the time.
The Measall devices seem well regarded, but I don't think I have seen any of their models being sold for under 600eur, usually seen them at +1000eur.

[BH3XON]

So, is there a low-cost VNA with a frequency as low as 100Hz that can be used to test the phase margin and gain margin of a switching power supply, considering that the crossover frequency of the switching power supply is only a few KHz?

[ftg]

I think the lowest cost option will be some oscilloscope with a Bode plot option. Like the entry level Keysight one's with a signal generator and Bode plot capability.
Or a Siglent scope combined with a Siglent signal generator, or the headless signal generator addon for them, but a seaprate signal generator would likely be better value long term.

Or at least that's my plan when I'll eventually have a use for that capability.

[Solder_Junkie]

So, is there a low-cost VNA with a frequency as low as 100Hz that can be used to test the phase margin and gain margin of a switching power supply, considering that the crossover frequency of the switching power supply is only a few KHz?

The low cost VNAs typically only go down to 50 KHz and I guess most users of a VNA are primarily interested in RF measurements as opposed to power supply and/or audio. If the USA Government will allow export to China, the Keysight E5061B ENA, with the LF option, goes down to 5 Hz, a bargain at $25,600 plus another $5,000 for the LF option!

SJ

[ftg]

Well, even the Keysight EDUX1052G can do Bode plots up to 20MHz with the built in signal generator, but at it's price one might as well get a Siglent scope, Siglent bench top signal generator and the Bode plot option for the Siglent.

[tautech]

Well, even the Keysight EDUX1052G can do Bode plots up to 20MHz with the built in signal generator, but at it's price one might as well get a Siglent scope, Siglent bench top signal generator and the Bode plot option for the Siglent.

It's a standard feature for all Siglent DSO's that support Bode, NOT an option.

[ftg]

Well, even the Keysight EDUX1052G can do Bode plots up to 20MHz with the built in signal generator, but at it's price one might as well get a Siglent scope, Siglent bench top signal generator and the Bode plot option for the Siglent.

It's a standard feature for all Siglent DSO's that support Bode, NOT an option.

Ah, that seems correct. A separate option "SDS1000X-E-FG" seems to only be required if one wants to use the SAG1021 external signal generator module and not a proper SDG signal generator.

[tautech]

Well, even the Keysight EDUX1052G can do Bode plots up to 20MHz with the built in signal generator, but at it's price one might as well get a Siglent scope, Siglent bench top signal generator and the Bode plot option for the Siglent.

It's a standard feature for all Siglent DSO's that support Bode, NOT an option.

Ah, that seems correct. A separate option "SDS1000X-E-FG" seems to only be required if one wants to use the SAG1021 external signal generator module and not a proper SDG signal generator.

Correct, although all/any options have 30 free trial uses before an option license is required for permanent usage.

But this is not the case for the USB SAG1021I AWG module and Bode plot use where there are no restrictions or option license required for the stimulus supply with Bode plot usage.

[Phil1977]

I think the lowest cost option will be some oscilloscope with a Bode plot option. Like the entry level Keysight one's with a signal generator and Bode plot capability.
Or a Siglent scope combined with a Siglent signal generator, or the headless signal generator addon for them, but a seaprate signal generator would likely be better value long term.

Or at least that's my plan when I'll eventually have a use for that capability.

Am I wrong that Bode plots by the scope are feasible only in the frequency range of the scope?

A serious 2GHz-scope is astronomically expensive, a 2GHz-Nano-VNA is <€200.

So far that was my reason for getting the VNA. It seems a quite affordable way to test antennas, filters, cables, transducers, etc... over the GHz-range.

[tautech]

I think the lowest cost option will be some oscilloscope with a Bode plot option. Like the entry level Keysight one's with a signal generator and Bode plot capability.
Or a Siglent scope combined with a Siglent signal generator, or the headless signal generator addon for them, but a seaprate signal generator would likely be better value long term.

Or at least that's my plan when I'll eventually have a use for that capability.

Am I wrong that Bode plots by the scope are feasible only in the frequency range of the scope?

Yes.

120 MHz is Bode plot limit for Siglent DSO's....if you have the scope model and AWG that supports it.

[ftg]

I think the lowest cost option will be some oscilloscope with a Bode plot option. Like the entry level Keysight one's with a signal generator and Bode plot capability.
Or a Siglent scope combined with a Siglent signal generator, or the headless signal generator addon for them, but a seaprate signal generator would likely be better value long term.

Or at least that's my plan when I'll eventually have a use for that capability.

Am I wrong that Bode plots by the scope are feasible only in the frequency range of the scope?

A serious 2GHz-scope is astronomically expensive, a 2GHz-Nano-VNA is <€200.

So far that was my reason for getting the VNA. It seems a quite affordable way to test antennas, filters, cables, transducers, etc... over the GHz-range.

Absolutely, for RF work the Nano and Lite VNA's are the superior option.

But the oscilloscope Bode plot was an answer to BH3XON's question about measuring pwoer supply control loops for gain and phase margin.
For those one wants to go below the 50 - 100kHz lower limit the of low cost VNA's.

[hem213]

thank you! I have been looking for an answer about this for weeks! Also I follow your twitter which is incredible by the way