ArcturusSDR
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Source code offers

Last updated 23 Oct 2026

ArcturusSDR is closed-source, but some of the libraries it uses are open source, and their licences give you rights we are glad to honour.

LGPL libraries: Qt

ArcturusSDR uses Qt (LGPL-3.0). It is linked dynamically: its libraries ship as separate files with the application, not built into it. Qt is the only LGPL library ArcturusSDR includes. USB radios also need libusb (LGPL-2.1), which you install yourself: ArcturusSDR does not include it.

For each release we offer, free of charge, the complete source of the Qt version it uses, with any changes we made. You can download them from the source downloads for that release, without an account.

Relinking ArcturusSDR with your own build

You may modify Qt's libraries and use your modified versions with ArcturusSDR:

  1. Download the source for the release you have, and make your changes.
  2. Build the library with the same version number and the same interface as the one shipped.
  3. Replace the library file of the same name in the application. On macOS the libraries are in ArcturusSDR.app/Contents/Frameworks; on Windows they are beside ArcturusSDR.exe in the folder ArcturusSDR is installed in.
  4. On macOS, sign the changed application for use on your own computer: codesign --force --deep --sign - ArcturusSDR.app.

ArcturusSDR then loads your library. If something here is unclear for a particular release, contact us and we will help.

Fraunhofer FDK AAC

ArcturusSDR uses the Fraunhofer FDK AAC Codec Library for Android, unmodified, to decode DRM audio. Its complete source, as used, is offered free of charge with each release on the source downloads page.

How long this offer lasts

We keep the source for each release available for as long as we offer that release, and for at least three years after.