Morse code in Cayo Largo del Sur, Cuba is coded as "UCL", and UCL in Morse code is transmitted on its radio frequency. In some countries, during periods of maintenance, the facility may radiate a T-E-S-T code () or the code may be removed which tells pilots and navigators that the station is unreliable. In Canada, the identification is removed entirely to signify the navigation aid is not to be used. In the aviation service, Morse is typically sent at a very slow speed of about 5 words per minute. In the U.S., pilots do not actually have to know Morse to
Morse code mnemonics to remember Morse codes lies in remembering words that begin with each appropriate letter and has so called long vowel (i.e. á é í ó ú ý) for every dash and short vowel (a e i o u y) for every dot. Additionally, some other theme-related sets of words have been thought out as Czech folklore. In Indonesia, one mnemonics commonly taught in scouting method to remember Morse codes lies in remembering words that begin with each appropriate letter and substituting the o vowel for every dash and other vowels (a, i, u, and e) for every dot. Morse code