Morse code and interword gaps may be lengthened so the word rate is only 5 words per minute. Using different character and text speeds is, in fact, a common practice, and is used in the Farnsworth method of learning Morse code. Some methods of teaching Morse code use a dichotomic search table. Morse Code cannot be treated as a classical radioteletype (RTTY) signal when it comes to calculating a link margin or a link budget for the simple reason of it possessing variable length dots and dashes as well as variant timing between letters and words. For the purposes of Information Theory
American Morse code states. In the United States, the ranks of amateur radio operators used to include many active and retired commercial landline telegraph operators, who preferred to use American Morse for their amateur radio transmissions, so the CW (continuous wave) amateur bands used to have a mixture of American and International Morse. However, today even U.S. amateurs use International Morse almost exclusively. American Morse code American Morse Code — also known as Railroad Morse—is the latter-day name for the original version of the Morse Code developed in the mid-1840s, by Samuel Morse and Alfred Vail for their electric telegraph. The "American" qualifier