DigiRadioDigiRadio
An open-source DAB+ and FM radio that sends its audio to your Bluetooth headphones or speaker in aptX Adaptive, with a DSP in the middle and an iPhone and iPad app.
DigiRadio v1
The board where it all started, assembled and in use: ADAU1701 DSP, FSC-BT1035 Bluetooth, USB-C power, on 6 layers and 50 × 90 mm.
Meet v1 →Why
I wanted a radio that receives DAB+ and FM and plays it on my own Bluetooth speaker or headphones with good quality, without going through a phone. Most DAB+ radios have their own small speaker, and the ones with Bluetooth usually receive it instead of transmitting it. So I designed my own.
How it works
The audio path is fully digital, I²S at 48 kHz and 24 bits: no conversions between the tuner and the Bluetooth link. The only DAC is the one in your headphones or speaker.
Radio
DAB+, DAB and FM with RDS, scrolling text, slideshow, alternate frequencies and band scan.
Web radio and phone
Web radio and your phone's audio over Wi-Fi go through the same DSP and out over Bluetooth.
Sound
Equaliser, audio presets, bass and stereo enhancement, computed by the ADAU1452 SigmaDSP.
Alarm clock
Alarms, sleep timer and a clock synced over the Internet.
Battery and optical out
It runs on a battery with a fuel gauge, and the S/PDIF output also connects it to an amplifier or a soundbar.
Fully open
Schematic, PCB, bill of materials and firmware are public: hardware under CERN-OHL-S v2, firmware under Apache 2.0. On GitHub you'll find board v2, which is also on PCBWay, and board v1.
