[http://earlyradiohistory.us/sec023.htm]
1906 BERLIN CONVENTION
A second international radio conference was held in Berlin, Germany in 1906, to deal with issues left over from the 1903 Conference. The result was a comprehensive agreement, the International Wireless Telegraph Convention (Convention Radiotélégraphique Internationale), which was adopted on November 3, 1906, and became effective July 1, 1908. Although U.S. representatives signed the agreement in 1906, the U.S. Senate did not ratify the Berlin Convention until April 3, 1912, and the President proclaimed U.S. adherence to the Convention effective May 25, 1912. (An overview of the effect of the 1906 Berlin Convention is included in the Renewed Efforts to Establish Control chapter of Linwood S. Howeth's 1963 History of Communications-Electronics in the United States Navy).
1910 SHIP ACT (AMENDED IN 1912)
Although the United States signed the 1906 Berlin Convention, it didn't pass any regulatory laws until the June 24, 1910 Act to require apparatus and operators for radio communication on certain ocean steamers, which required larger vessels of all nationalities visiting U.S. ports to install radio equipment by July 1, 1911.
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