Morse code become commonly available until around 1920. Until 2003, the International Telecommunication Union mandated Morse code proficiency as part of the amateur radio licensing procedure worldwide. However, the World Radiocommunication Conference of 2003 made the Morse code requirement for amateur radio licensing optional. Many countries subsequently removed the Morse requirement from their licence requirements. Until 1991, a demonstration of the ability to send and receive Morse code at a minimum of five words per minute (wpm) was required to receive an amateur radio license for use in the United States from the Federal Communications Commission. Demonstration of this ability was still
Hog-Morse For instance, the international code has only two symbols, dots and dashes, but the American code has several lengths of dash. There is a distinction between "L" () and "T" (). Also, in the international code the space between symbols within a character is always the same, but American Morse has two different spaces. The letters "S" (), "C" (), and "R" () all consist of three dots, but the timing is different in each case. A frequently quoted, but possibly apocryphal, story from the historical period concerns the similarity of "L" and "T" in the American code. A company