---
title: Firmware Update
description: Upgrade firmware via USB virtual U-disk
---

import { Aside, Steps } from '@astrojs/starlight/components';
import firmwareUpgrade1 from '../../../../assets/screenshots/firmware-upgrade-1.png';
import firmwareUpgrade2 from '../../../../assets/screenshots/firmware-upgrade-2.png';
import firmwareUpgrade3 from '../../../../assets/screenshots/firmware-upgrade-3.png';
import firmwareUpgrade4 from '../../../../assets/screenshots/firmware-upgrade-4.png';
import firmwareUpgrade5 from '../../../../assets/screenshots/firmware-upgrade-5.png';
import firmwareUpgrade6 from '../../../../assets/screenshots/firmware-upgrade-6.png';

Firmware updates add features, fix bugs, and improve measurement accuracy. The NanoVNA-F V3 uses a simple USB file-copy method -- no special flashing software is required.

## Download the firmware

<Steps>
  1. Visit the official firmware page at [sysjoint.com](https://www.sysjoint.com).
  2. Locate the latest firmware file for the NanoVNA-F V3.
  3. Download the file. It will be named **`update.bin`**.
</Steps>

<img src={firmwareUpgrade1.src} alt="Firmware download page on sysjoint.com" />

<Aside type="caution">
  Only download firmware from the official sysjoint.com website. Third-party firmware files may damage your device or void your warranty.
</Aside>

## Enter U-disk mode

<Steps>
  1. Connect the NanoVNA-F V3 to your computer via the **USB-C** cable.
  2. **Power off** the device if it is currently running.
  3. Hold the **middle button** and power on the device simultaneously.
  4. The device enters U-disk mode and appears as a removable USB drive on your computer.
</Steps>

<img src={firmwareUpgrade2.src} alt="NanoVNA-F V3 connected via USB-C for U-disk mode" />

<img src={firmwareUpgrade3.src} alt="Device appearing as USB drive on computer" />

## Copy the firmware file

<Steps>
  1. Open the USB drive on your computer.
  2. Copy the **`update.bin`** file to the root of the USB drive.
  3. Wait for the file copy to complete fully.
  4. **Safely eject** the USB drive from your operating system.
</Steps>

<img src={firmwareUpgrade4.src} alt="Copying update.bin to the USB drive" />

<img src={firmwareUpgrade5.src} alt="File copy in progress" />

<Aside type="caution">
  Do not disconnect the USB cable or power off the device while the file is being copied. Interrupting the transfer can leave the device in an unusable state.
</Aside>

## Apply the update

<Steps>
  1. Disconnect the USB cable.
  2. Power off the NanoVNA-F V3.
  3. Power it back on normally (without holding any buttons).
  4. The device detects `update.bin` and applies the firmware update automatically.
  5. The update process takes a few seconds. The device restarts when finished.
</Steps>

<img src={firmwareUpgrade6.src} alt="Firmware update complete" />

## Verify the update

After the device restarts:

<Steps>
  1. Tap <span class="menu-path">CONFIG → ABOUT</span>.
  2. Check that the firmware version matches the version you downloaded.
</Steps>

<Aside type="tip">
  After a firmware update, it is good practice to recalibrate the device. Some firmware updates may alter calibration behavior or add new calibration features.
</Aside>

<Aside>
  The `update.bin` file is automatically deleted from the device storage after the update completes. You do not need to remove it manually.
</Aside>