It also had the first radiotelegraph in the continent in 1927. A Marconi radiotelegraph station was constructed in 1909. Currently, only one class of license, the Radiotelegraph Operator License, is issued. This was the first successful transatlantic radiotelegraph message in 1902. In 1912 the first International Radiotelegraph Convention was held in London. There was no change to this allocation at the 1932 International Radiotelegraph Conference in Madrid. The International Radiotelegraph Convention at Washington in 1927 revised the list of markings. The Radiotelegraph Act of 6 June 1913 established the initial Canadian policies for radio communication. SINPO is the official radiotelegraph signal reporting codes for international civil aviation and ITU-R.