^Mhm, close to the Public Conveniences. It was essentially the wizarding broadcasting service for mainly music and news related things, but, as Mantaguy said, it was used in Deathly Hallows to proclaim those muggle-borns captured by Snatchers that were considered inferior to the pure-blood-thirsty team behind Voldemort (who killed Charity Burbage just because she taught Muggle Studies at Hogwarts). The wizarding community has developed a radio, yes, but it is run by magic and not technology, like Hogsmeade's clock system.