--- On Wed, 2/9/11, Bob Olhsson <[log in to unmask]> wrote:

> Who is probably Bell Labs and when is
> probably shortly after the end of WW1.

And predating radio.  AT&T was also involved in
developing public address equipment.  There's an
interesting article here about a non-radio
"broadcast" AT&T did from Arlington Cemetery
to Madison Square Garden for Armistice Day in
1921:

http://homepage.mac.com/oldtownman/recording/armistice.html