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Things you can do with a Nano VNA

When it comes to value for money, the new generation of VNAs is unbeatable. Their screens are small and adjustments are sometimes fiddly. However they allow tests and experiments that were only in reach of the small number of hams with an RF test lab a few short years ago. And they now cost under $100!

Don't know what a VNA (or Vector Network Analyser) is? It's a universal RF test instrument with a display where you can see how selected characteristics of an antenna, component or filter vary with frequency. Those characteristics can include things like reactances, impedances and losses.

Unlike most simple pieces of test gear we're used to (multimeters, LC meters, frequency counters, antenna analysers, etc) with just one connection for the part under test, VNAs have two. In crude terms one is an RF output while other is an RF input connected to a receiver with a spectrum display screen. Sometimes you'll use one connection while at other times you'll use both.

There's some good introductory videos on Nano VNAs eg by W2AEW. I recommend watching them for more information on how Nano VNAs work and how to set them up. The videos below show some things I've done with mine.

1. Antenna analyser

Use an antenna coupler? Don't have a transceiver with an inbuilt VSWR indicator? Use your Nano VNA to adjust your coupler so it presents a 50 ohm load to the transceiver. The first video below shows how. The second video shows the Nano VNA's use with some oblong loops I was experimenting with.

 

2. Signal generator/low power beacon

A Nano VNA can put out a signal useful for various tests. You can use the CW function to put out a carrier on one frequency. Or you can set lower and upper limits to emit a signal that sweeps across a frequency range. That can be useful to provide a distinctive sound for a test beacon transmitter. Some experiments I've done here:

 

3. Nano VNA spectrum scope

A Nano VNA can make a basic spectrum scope. There are limitations with regards to resolution but if you set the range tight enough it can still be useful.

 

4. Testing band pass, low pass and crystal filters

Are the filters that you build really any good? What about those unmarked crystal filters you might find in old radio equipment? A Nano VNA can test these and more, as shown below:

 

Sources of Nano VNAs

Don't have a Nano VNA yet? These may be useful places to get them. Note that they do vary so make your choice wisely. For instance mine only goes up to 900 MHz but 1.5 GHz units are desirable due to them covering the 23cm amateur band. And some have bigger or better screens. Highly desirable as some numbers on the smaller screen models are very small.

 

Disclosure: I receive a small commission from items purchased through links on this site.
Items were chosen for likely usefulness and a satisfaction rating of 4/5 or better.

 

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