A compact bridge for your NanoVNA

NanoVNA, untethered.

VNA Air connects a USB NanoVNA to an ESP32-S3 bridge, then brings live sweeps and antenna measurements to a browser or iPhone. Tune bands, compare SWR, and keep the instrument's measured sweep grid in sync with your app.

Open the VNA Air app Flash an ESP32-S3

A better way to work at the antenna

Use the bridge with the VNA Air browser app or the native iOS companion. The browser app also includes a simulated device so you can explore without hardware.

01 / Sweep

Live measurements

Run band sweeps, inspect the SWR curve, and repeat tune while adjusting your antenna.

02 / Bands

See the whole band

Compare amateur-band results at a glance, then open a full sweep to locate a resonance.

03 / Wireless

Move freely

The ESP32-S3 relays NanoVNA measurements over Bluetooth LE to supported apps.

See it in action

Real screens from the VNA Air iPhone and Apple Watch apps, captured with the built-in simulated bridge. Select any image to view it full size.

VNA Air iPhone app bands overview with an SWR result for each amateur band — Bands overview

VNA Air iPhone app showing a 20m band sweep and its SWR curve — 20m sweep

VNA Air iPhone app in repeat tune mode, updating SWR while the antenna is adjusted — Repeat tune

VNA Air iPhone app showing 40m band detail — 40m band detail

VNA Air iPhone app setup screen for connecting to the bridge — Setup and bridge connection

On Apple Watch

VNA Air Apple Watch app showing the bands list — Bands

VNA Air Apple Watch app showing a band scan result — Band scan result

VNA Air Apple Watch app showing live tune SWR — Live tune

Get the hardware

VNA Air runs on an ESP32-S3 board. Get it ready to use with the kit, or buy a board below and flash the firmware yourself for free.

Ready to use

VNA Air Kit

Flashed, tested, and ready to pair.

Seeed Studio XIAO ESP32S3 with the current VNA Air firmware already flashed
Bench tested against a real NanoVNA before it ships
USB-C cable to connect your NanoVNA
USB-C OTG adapter (power and data splitter)
Printed quick start card

$49 Buy the kit

Works with the free VNA Air web app today, and with the iPhone app when it arrives on the App Store.

Deployment target

Seeed Studio XIAO ESP32S3

The small board VNA Air was built and tested on, and the board the firmware on this page targets.

Buy on Amazon

Three ESP32-S3 development boards with dual USB-C connectors

Full-size option

ESP32-S3 Development Board (N16R8), 3 pack

A full-size dev board option built on the same ESP32-S3, with header pins that make experimenting easy.

Buy on Amazon

USB-C OTG splitter adapter with charging port and USB data port

Power splitter

USB-C OTG Splitter with Charging Port

One USB-C plug splits into a charging port and a USB data port, so the XIAO mini can take power in while data goes out to your NanoVNA. Included in the VNA Air Kit.

Buy on Amazon

The board and adapter links are Amazon affiliate links. If you buy through them, Robb may earn a small commission at no extra cost to you. The VNA Air Kit is sold directly by Robb, with no affiliate involved.

Flash VNA Air to your S3

The firmware is built for the Seeed Studio XIAO ESP32S3 with 8 MB flash. The installer writes the bootloader, partition table, and VNA Air firmware.

Install from your browser

Use a desktop version of Chrome or Microsoft Edge on this secure GitHub Pages site. Connect the S3 directly to your computer with a USB data cable.

Disconnect the NanoVNA while flashing.
Choose the ESP32-S3 serial port when prompted.
Keep the board connected until the installer reports completion.

Download firmware image (.bin)

From flash to first sweep

Flash the bridge

Install the firmware above using a desktop browser and a USB data connection.

Connect your NanoVNA

Plug the NanoVNA into the ESP32-S3 USB host connection, directly or through a powered hub.

Open VNA Air

Connect to the VNA Air BLE service in the app and start a sweep.