Beware of cheap underperforming clones
As of October 2021 all non-Plus/Plus4 hardware are clones (we have stopped producing older versions since October 2020), many of which perform badly, and users have reported software/firmware incompatibility. If a clone is selling for much cheaper than the official store it likely uses salvaged or reject parts and will not meet specifications. See official stores and look for V2 Plus/Plus4 versions only to avoid getting a bad clone.
Only guaranteed to be compatible with V2 hardware listed here.
On Windows, please run CypressDriverInstaller_1.exe first to install the USB-CDC driver. On Linux and MacOS, no drivers are needed. Download and run .AppImage or .dmg directly.
If using Windows 10, you may need to update your NanoVNA firmware to the latest version.