It's a French collective curating rare and exotic nostalgia tunes since 2013 (https://www.newyorker.com/culture/culture-desk/radiooooo-the...). It was co-created by a member of the Polo & Pan duo (https://www.discogs.com/artist/4106352).

An up to date revision of the site is available at: https://radiooooo.app

Here's a little helper script to listen Radiooooo from the command line: https://github.com/vikbez/radiooooo-cli