Build an FM radio using an RTL-SDR dongle
Raspberry Pi FM Radio
For the Pi FM radio project in this article, I tried a few different arrangements, but I found that an LCD HAT (hardware attached on top) with buttons (Figure 4) worked best. However, other options such as a PiFace digital HAT (Figure 5) or a button HAT could also be used.
The LCD Python libraries will vary according to the hardware used; however, most LCD HATs are based on the Adafruit libraries [4].
The Python code for the LCD HAT (Listing 2) is based on the simple test code with some additional logic for an LCD button interface and some predefined radio frequencies. The main code loops through, looking at each of the buttons with the lcd.is_pressed()
function. The LCD.UP
and LCD.DOWN
buttons are used for volume control, and the LCD.LEFT
and LCD.RIGHT
buttons cycle through the predefined radio stations. The lcd.clear()
and lcd.message()
functions show the new radio station information on the LCD HAT. In my testing, I used a 0.25-second delay on all the button presses, although you might need to tune this value for your hardware and usage.
Listing 2
Pi FM Radio with an LCD HAT
Summary
Creating a homemade FM radio is just one of the many interesting applications for SDR utilities and the low-cost RTL-SDR dongle [5]. In the future, I would like to add a Python Tkinter or web interface to my FM radio application.
Infos
- About RTL-SDR: http://www.rtl-sdr.com/about-rtl-sdr/
- GNU Radio: https://www.gnuradio.org/
- Code for this article: ftp://ftp.linux-magazine.com/pub/listings/linux-magazine.com/206/
- Adafruit libraries: https://github.com/adafruit/Adafruit_Python_CharLCD
- See more of Pete's Projects: https://funprojects.blog
« Previous 1 2
Buy this article as PDF
(incl. VAT)
Buy Linux Magazine
Subscribe to our Linux Newsletters
Find Linux and Open Source Jobs
Subscribe to our ADMIN Newsletters
Support Our Work
Linux Magazine content is made possible with support from readers like you. Please consider contributing when you’ve found an article to be beneficial.
News
-
Canonical Bumps LTS Support to 12 years
If you're worried that your Ubuntu LTS release won't be supported long enough to last, Canonical has a surprise for you in the form of 12 years of security coverage.
-
Fedora 40 Beta Released Soon
With the official release of Fedora 40 coming in April, it's almost time to download the beta and see what's new.
-
New Pentesting Distribution to Compete with Kali Linux
SnoopGod is now available for your testing needs
-
Juno Computers Launches Another Linux Laptop
If you're looking for a powerhouse laptop that runs Ubuntu, the Juno Computers Neptune 17 v6 should be on your radar.
-
ZorinOS 17.1 Released, Includes Improved Windows App Support
If you need or desire to run Windows applications on Linux, there's one distribution intent on making that easier for you and its new release further improves that feature.
-
Linux Market Share Surpasses 4% for the First Time
Look out Windows and macOS, Linux is on the rise and has even topped ChromeOS to become the fourth most widely used OS around the globe.
-
KDE’s Plasma 6 Officially Available
KDE’s Plasma 6.0 "Megarelease" has happened, and it's brimming with new features, polish, and performance.
-
Latest Version of Tails Unleashed
Tails 6.0 is based on Debian 12 and includes GNOME 43.
-
KDE Announces New Slimbook V with Plenty of Power and KDE’s Plasma 6
If you're a fan of KDE Plasma, you'll be thrilled to hear they've announced a new Slimbook with an AMD CPU and the latest version of KDE Plasma desktop.
-
Monthly Sponsorship Includes Early Access to elementary OS 8
If you want to get a glimpse of what's in the pipeline for elementary OS 8, just set up a monthly sponsorship to help fund its continued existence.