Well into WWI, it was the animal alternative to Marconi's system for sending wireless long-distance messages
[DOC] [TLE] radio facts, information, pictures | Encyclopedia.com articles about ... [PAR] The radio converts these electromagnetic waves, called a signal, into sounds ... 
Guglielmo Marconi successfully sent the first radio message across the ... Rather, 
it received buzzing sounds created by a spark gap transmitter sending a signal ... 
During the WWI, many advancements were made to the radio making it more... [DOC] [TLE] Nikola Tesla: The Guy Who DIDN'T "Invent Radio" [PAR] Nov 1, 2012 ... And about that 1943 Supreme Court ruling -- Marconi Wireless Tel.