Raspberry Pi Bluetooth Radio

This project aims to turn a Raspberry Pi (in this case, the Pi Zero 2 W) into a radio receiver that can play received radio over a connected Bluetooth device, such as headphones, without any internet connection. My goal was to listen to news and music on the go without using data for internet radio streaming.

This article is intended as a tutorial. Feel free to contact me with any questions here in the comments or via the contact page.

Hardware Requirements:

• Raspberry Pi with a 64-bit processor (e.g., Zero 2 W)
• SDR Dongle with RTL2832U chipset
• Optional: PiSugar battery
• Optional: Case for the Pi
• Computer for connection and setup, or alternatively the Termux app on Android

Step 0: Prepare the Operating System

If you haven’t already, install the latest version of Raspbian on your Pi (tutorials can be found, for example, here), connect to your Pi via ssh (ssh <username>@<ip-address>) and perform a full update:

sudo apt update && sudo apt dist-upgrade -y

Step 1: Install Programs

Next, you can install all the necessary programs. Restart the Pi once to update the necessary permissions.

sudo apt install rtl-sdr bluez-alsa-utils -y
sudo reboot

Optional: If you are using a PiSugar battery, you can also install the program for it

wget https://cdn.pisugar.com/release/pisugar-power-manager.sh
bash pisugar-power-manager.sh -c release

Step 2: Connect Bluetooth Device

Now you can connect your Bluetooth device. Replace the placeholder with the MAC address of your own Bluetooth device.

bluetoothctl
scan on
# Now search for the name of your device and
# note the MAC address next to it,
# e.g. EF-9C-97-9E-E2-A9. Replace "MAC" with this
# address from now on.
pair MAC
trust MAC
connect MAC
exit

Step 3: Create Scripts and Install Service

Now create the following scripts in your home directory and note the file path. I use nano FILENAME to create them, then save the file with CTRL+x -> y -> ENTER. Replace the path and your username in the script according to your settings.

radio.sh: Broadcast frequency is set to 90.8 MHz, replace “90.8M” with your desired receiving frequency

#!/bin/bash
/home/luca/connect.sh
rtl_fm -f 90.8M -s 200k -r 48000 | aplay -r 48000 -f S16_LE -D bluealsa

connect.sh:

#!/bin/bash

# Replace with your Bluetooth device's MAC address
DEVICE_MAC="EF-9C-97-9E-E2-A9"

echo "Starting Bluetooth connection attempts to $DEVICE_MAC"

while true; do
    # Check connection status
    if bluetoothctl info $DEVICE_MAC | grep -q "Connected: yes"; then
        echo "Successfully connected to $DEVICE_MAC"
        break
    else
        echo "Connection failed or device not found. Retrying..."
    fi

    # Start bluetoothctl commands
    echo "Attempting to pair and connect..."

    bluetoothctl connect $DEVICE_MAC

    # Wait before retrying
    sleep 2
done

Make the scripts executable and create a systemd service:

chmod +x radio.sh
chmod +x connect.sh
sudo nano /etc/systemd/system/blueradio.service

[Unit]
Description=Bluetooth radio service
After=bluetooth.target

[Service]
ExecStart=/home/luca/radio.sh
Restart=always
User=YOUR_USERNAME

[Install]
WantedBy=multi-user.target

Finally, enable the service and restart the system. After the reboot, music should play automatically through your Bluetooth device.

sudo systemctl daemon-reload
sudo systemctl enable blueradio
sudo reboot

If you encounter any issues with any of these steps, or have a suggestion for improvement, feel free to leave a comment under this article!