HVDN Notebook: Presentation: NanoVNA Overview

Before the popular Hackaday website made the wider hobbyist world aware of the "Nano VNA", there has been continued discussion taking place on the Northstar Digital Net about this inexpensive device and its different capabilities.

Hudson Valley resident, Neil Goldstein W2NDG, recently gave a fantastic presentation in person at the Overlook Mountain Amateur Radio Club (OMARC) about this sub $50 USD device if shopped for carefully and its abilities for analyzing antennas, finding breaks in a length of feed-line, tuning filters and so much more.

Neil has shared his slides on his Fofio blog and real time discussion can be had with other users of the Nano VNA every Tuesday on the Northstar Digital Net run by Jim Miller WA2UMP. A copy of the presentation has also been added to the HVDN Presentation Library in the affiliated section.

For those not familiar with the Hudson Valley, the OMARC club is one of many local member driven organizations and caters to serving amateur radio operators in Dutchess and Ulster counties along with a wider reach into Columbia and Greene Counties.

Based on a quick chat with Neil who is a member of multiple organizations such as the Long Island Mobile Amateur Radio Club (LIMARC) to the south of the Hudson Valley, here are are some more details if you were not among those who attended the live presentation in Kingston, NY at the recent OMARC meeting.

What was the main reason you bought the Nano VNA?

Mostly for antenna analysis. I have an antenna analyzer that I built from a project article, but it maxes out at 30 MHz. It would be nice to have something for testing any kind of antenna I might use from LF antennas up through 70 Centimeter antennas. I also have quite a collection of unidentifiable HT antennas that I can now test and label accordingly. Additionally, it will come in handy for testing bandpass, and lowpass filters from some of my future kit projects.

Is it fair to compare a $50 USD Nano VNA to a commercial $11,000 USD piece of equipment?

In most cases I would say NO. I see this argument all the time on some of the email groups where people complain that the IC-7300 just doesn't have as good a waterfall as the (insert $5000 radio here). We're used to seeing people comparing apples to rutabagas in this hobby. In this case though, it holds up for casual use. Very few of us need the accuracy of the $11K model, and something like this is what we have been looking for, but it's nice to know that it does compare on some level.

Will it replace any other "test equipment" you currently use?

I'll probably not use my homemade antenna analyzer much anymore.

What do you think is the best way to get started with the Nano VNA?

There are multiple websites with getting-started articles on these, as well as a very active Groups.io group. Buy a decent one (Amazon seller KKMOON is where I got mine) and start with learning the calibration steps, and try out the basics. Stick a Baofeng antenna on it and run SWR. Watch some YouTube videos. There are plenty to choose from.

How would a user know the readings they see are accurate?

Test a known quantity. Maybe an antenna from a major-brand radio, although the cheapies are surprisingly accurate. My Baofeng dual-band antennas showed clear SWR dips at 446 MHz and 146 MHz. Test a commercial lowpass or bandpass filter with a known cutoff. Compare output from the device with someone else's antenna analyzer output if you don't have one.

Why is your blog called Fofio?

Fofio was the name of my imaginary friend when I was 2-3 years old. I think the name was some sort of toddler-mispronunciation of Volvo, but I'm not sure. It was also the name of the only dog my family had when I was growing up (named by guess-who).

Are any other "test and measurement devices" on your radar for the budget minded hobbyists?

There will be future versions of the NanoVNA coming with more capability and more features. Watch the forums, and the groups.io NanoVNA group for info. Other than that, I have seen several very inexpensive scope projects around. I don't know of any specific ones, but the large buildathon at this years FDIM QRP get-together was focused on one of these cheap oscilloscopes. Simple spectrum analyzers are also out there, based on RTL-SDR dongles, or SDR radios like the AirSpy and/or SDRplay models.

Nano VNA: Further Reading

If you have not already seen Neil's great presentation, he includes some helpful links and we are sharing them here just for back up. Hudson Valley Digital Network (HVDN) looks forward to sharing more about this great piece of equipment in future articles, on the air discussion and at various in person meetings.