Morse code Morse is dah-dah-di-dah, which can be memorized by the phrase "God save the Queen", and the Morse for "F" is di-di-dah-dit, which can be memorized as "Did she like it." A well-known Morse code rhythm from the Second World War period derives from Beethoven's Fifth Symphony, the opening phrase of which was regularly played at the beginning of BBC broadcasts. The timing of the notes corresponds to the Morse for "V", di-di-di-dah, understood as "V for Victory" (as well as the Roman numeral for the number five). Prosigns for Morse code are special (usually) unwritten procedural signals or symbols that
Morse code per minute (wpm) or characters per minute (cpm). Characters have differing lengths because they contain differing numbers of dots and dashes. Consequently, words also have different lengths in terms of dot duration, even when they contain the same number of characters. For this reason, a standard word is helpful to measure operator transmission speed. "PARIS" and "CODEX" are two such standard words. Operators skilled in Morse code can often understand ("copy") code in their heads at rates in excess of 40 wpm. In addition to knowing, understanding, and being able to copy the standard written alpha-numeric and punctuation characters or