There’s something about when someone claims to have made a supper small (or even the smallest version of something) that immediately draws me in. This build by maker Milen is no exception! He cites yoradio as his inspiration.
The radio is designed by simple assembling of two small boards. The first one is ESP32 C3 Supermini development board – widely available in lot online Internet shops. It costs around 2 USD. The other part is small custom bord from Tindie containing PCM5102A I2S Audio codec and LM4880M Headphone amplifier. Of course another audio codec board based on the PCM5102A chip can be used. Such boards are also available in the online selling platforms. Their disadvantage – they do not have power amplifier. Their output is linear and external amplifier has to be used. If you decide to implement the first version – both modules are simply to solder together using a pin header. The pins are aligned to match together. For the second version the following connection have to be implemented: