For many of us, the construction of a classic FM radio was one of the very first projects we took on when getting started with DIY electronics. And for good reason. Radio waves are fascinating, they’re everywhere, and they’re free! Radio brings all kinds of information and entertainment—including music, news, and sports—to people all over the world. It remains an extremely popular medium for content delivery, and it doesn’t even require an Internet connection. The ScoutMakes FM Radio Kit provides an engaging exploration of Frequency Modulation (FM) radio. And, thanks to BLE, you can control it from across the room.

To build an FM radio receiver, you would typically need several components, including resistors, capacitors, transistors, and an amplifier. But thanks to advancements in technology, there are now several single-chip, integrated-circuit (IC) receivers on the market. To make the FM Radio Kit as accessible and easy-to-use as possible, TinkeringTech chose one such chip—the RDA5807M, which is a broadcast FM stereo tuner with a fully integrated synthesizer and a powerful low-IF digital audio processor—and they baked it into a PCB that complies with the Adafruit Feather standard. The chip is programmable by way of a CircuitPython library.

The ScoutMakes FM Radio Kit can also receive and process Radio Data Service (RDS) content. RDS is a communications protocol for embedding small amounts of digital data within conventional FM radio broadcasts. Examples include time, station identification, and programming information. (If you have a modern car stereo, you’ve probably seen RDS used to display the name of the song that is playing.)

FM Radio Kit Features and Specifications:

RDA5807M single-chip FM receiver
Controllable over BLE using an iOS or Android app
Powered by the LiPo battery in the Azul board
High-quality stereo audio output
Built-in volume and bass control
Received signal strength indicator (RSSI) information
Station scanning and presets are supported in code
Radio Data Service (RDS) information available for display
Adafruit CircuitPython library
SparkFun Qwiic connector for easy, solderless attachment of other I²C devices
User-assignable push-buttons for control
3.5mm audio jack

Azul Features and Specifications:

Powered by an ARM Cortex M4F (with hardware floating point acceleration) running at 64 MHz
1 MB flash and 256 KB SRAM
Native open source USB stack, pre-programmed with UF2 bootloader
BLE-compatible 2.4 GHz radio
Up to +8 dBm output power
Built-in 128 x 32 pixel OLED display
NeoPixel LED
USB type-C connector
Built-in battery charger and 100 mAh LiPo battery
1.7 to 3.3 V operation with internal linear and DC/DC voltage regulators
21 GPIO, six 12-bit ADC pins, and up to 12 PWM outputs (three PWM modules with four outputs each)
A red LED for general-purpose blinking (pin #3) and a NeoPixel for multi-color visual feedback
A power switch
A reset button
Four mounting holes
Works out of the box with FeatherWing add-on boards