International Radiotelegraph Convention (1912)

The International Radiotelegraph Convention (1912) established an agreement to allow the exchange of radio telegraphs (with the intention to connect this new network to wired telegraph). International callsigns, replacing the three letter callsigns prevalent then. Major world powers were given single prefixes such as N/K/W (United States), A (Germany), F (France), B (Great Britain). British colonies were given the call signs starting with V. The convention was signed at the International Radiotelegraph Conference in London on July 5, 1912. Additional regulations were added in 1927 (effective 1929) in Washington, D.C..

The following countries were party to the conventions:

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