I helped a friend "restore" a 1938 Zenith floor-standing radio, changing it into an MP3 player. We collected old radio broadcasts ("Whistler", "Shadow", "Grand Ole Opry", "Burns and Allen", "War of the Worlds", etc) and separated the content into folders. I use a Teensy to read the capacitance of the tuner to select a folder on the SD card, then randomly choose an MP3 file to play within that folder. I use the audio library to inject hiss in between "stations" and other special effects.
The project turned out so well that I wanted one for myself, but much smaller. I purchased a beat-up RCA 118 radio ( https://radioatticarchives.com/radio.htm?radio=11343 ) and had my friend build a new case. We chopped down the chassis so the entire radio is about a 12" cube. I use one band for the old historical programs and another for modern music. On the modern-music band I have one "station" that is random-play across everything in the band.

Some Photos:

Cut-down chassis
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Chassis in new case
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New electronics
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Completed "radio"
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