ESP32 DAB+ open‑radio build
An open‑source DAB+ receiver pairs an ESP32 SoC with a Skyworks SI4684 digital radio chip to give hobbyists a radio‑first embedded build rather than an internet‑streaming project. The writeup includes hardware details and could be a practical weekend project if you want over‑the‑air DAB reception on cheap silicon. It’s a neat example of combining modern microcontrollers with radio front‑ends for tangible maker results. (cnx-software.com)
Digital radio is broadcast like a bundle of data packets, not a continuously varying wave, so one transmitter can carry multiple stations plus text and images in the same slice of spectrum. The “plus” in Digital Audio Broadcasting Plus means it uses newer audio coding than the original Digital Audio Broadcasting system, which is why broadcasters can fit more services into one multiplex. (skyworksinc.com) A receiver for that signal needs two jobs done in sequence: one chip has to pull the radio signal out of the air, and another controller has to run the screen, buttons, and station logic. In this build, the Skyworks SI4684 handles the radio side while an Espressif ESP32 handles the user interface and firmware. (pe5pvb.nl) The surprise is that this is not another internet radio hiding behind a Wi‑Fi board. It is a real over‑the‑air set built around the SI4684, a single-chip receiver family that Skyworks says supports Digital Audio Broadcasting, Digital Audio Broadcasting Plus, frequency modulation radio, and other broadcast standards. (cnx-software.com, skyworksinc.com) That matters for hobbyists because an ESP32 by itself is a good little computer but not a full Digital Audio Broadcasting Plus radio front end. The SI4684 adds the tuner, baseband processing, and audio path, so the ESP32 can spend its time acting like the dashboard instead of trying to be the engine. (skyworksinc.com, cnx-software.com) The project comes from Sjef Verhoeven, who publishes under PE5PVB, and he says he designed it for the 60th VRZA Radio Camp Week in 2024. The public repository includes KiCad design files, schematics, Gerbers for board fabrication, STL files for the enclosure, and firmware source code under the GNU General Public License version 3.0. (pe5pvb.nl, github.com) The hardware looks like a small tabletop radio instead of a bare development board. Verhoeven’s writeup says the set uses a color liquid-crystal display, three push buttons, and two rotary encoders, with stereo cinch outputs and a separate headphone amplifier. (pe5pvb.nl, fmdx.org) The software side is unusually complete for a maker radio. The GitHub readme lists support files for images, a serial protocol document, display libraries, and tested button actions such as switching services, changing memory channels, opening menus, and toggling slideshow view. (github.com) There is also a practical reason this build stands out in 2026: parts of Europe and Australia still have active Digital Audio Broadcasting Plus coverage, but many cheap hobby projects default to web streams because radio silicon is harder to integrate than Wi‑Fi. This design lowers that barrier by packaging the hard part into a documented board that a weekend builder can actually reproduce. (skyworksinc.com, cnx-software.com, github.com) The project is still active rather than frozen as a one-off camp badge. The repository shows 92 stars and 17 forks when checked on April 10, 2026, and the readme warns that the main branch is ongoing development while tested firmware is distributed through releases. (github.com) The nicest part is how old-school and modern parts meet in one box. A radio signal still arrives through an antenna, but the tuning, menus, graphics, and firmware updates now ride on the same cheap microcontroller ecosystem people already use for smart lights and sensor boards. (skyworksinc.com, github.com)
