As a kid, I used to build AM radios but never quite managed to build FM radios. They were just too complicated. Nowadays, you can get a complete FM radio tuner on a chip but these chips are surface-mount components and difficult for a hobbyist to work with. Fortunately, Sparkfun makes a breakout for the Silicon Laboratories Si4703 FM radio tuner chip (datasheet), which breaks out all pins. I will show you how you can build a complete FM radio around this breakout and use an Arduino to control the tuner functions over the built-in two-wire control interface. Sparkfun provides a complete library making this easy to program.
At the same time, I added a cool little OLED display to the project with very high contrast and very low power consumption. Last but not least, I will show you how you can build a great-sounding mono audio amplifier from a minimum of parts. The finished radio runs on three AA-batteries for many, many hours.
Stop breadboarding and soldering – start making immediately! Adafruit’s Circuit Playground is jam-packed with LEDs, sensors, buttons, alligator clip pads and more. Build projects with Circuit Playground in a few minutes with the drag-and-drop MakeCode programming site, learn computer science using the CS Discoveries class on code.org, jump into CircuitPython to learn Python and hardware together, or even use Arduino IDE. Circuit Playground Express is the newest and best Circuit Playground board, with support for MakeCode, CircuitPython, and Arduino. It has a powerful processor, 10 NeoPixels, mini speaker, InfraRed receive and transmit, two buttons, a switch, 14 alligator clip pads, and lots of sensors: capacitive touch, IR proximity, temperature, light, motion and sound. A whole wide world of electronics and coding is waiting for you, and it fits in the palm of your hand.