If you manage to find a genuine Grundig 890_V204.bin file from a 2017 archive, back it up to three different clouds. You will be a hero to the small, dedicated cult of Sonoclock owners. For the other 99% of you: put down the USB stick, press the "Alarm Off" button, and enjoy the radio for what it is—a charming, imperfect classic.
Please check the sticker on the back or bottom of your device and provide the full type/model number (e.g., “Grundig Sonoclock 890 SC – GN…”). That will confirm whether your device actually supports firmware updates at all. Grundig Sonoclock 890 Web Firmware Update
Ensure the device is connected to the internet via LAN or WLAN. Access the menu. If you manage to find a genuine Grundig 890_V204