A new shaped web portal of Rai Teche, the vast historical archive of Italian public broadcaster Rai, is offering a renovated opportunity to track 90 years of radio and 60 of television in Italy, including some publications from Rai's libraries.
The new portal http://www.teche.rai.it/ does lead to a alphabetic ordered list of personalities on http://www.teche.rai.it/personaggi-radio-e-tv-in-ordine-alfabetico/
Just pay attention at the indexed key: it's the first name and not the surname to be listed first.
If you search for Marconi, for instance, just get Guglielmo, his Christin name.
Finally you'd find a couple of clips of Vatican Radio foundation (1931) and experiments conducted on the following year.
In the library, 90 years of "Radiocorriere" (the Italian "Radio Times") are available under http://www.radiocorriere.teche.rai.it/Default.aspx
Everything is Italian, of course, but radio matters are a common language to everyone involved. Just try.