Sources

Every table on this site rests on named sources. The international alphabet follows ITU-R M.1677-1; other alphabets follow national rules or the best references there are. Below, each table shows its sources, how sure the folio is of it, and the day it was last compared with them by hand.

§ 1Alphabets

Table	Sources	Confidence	Checked
International (ITU)	Recommendation ITU-R M.1677-1: International Morse codeInternational Telecommunication Union. Annex 1, Part I, §1.1 and §2 (pp. 2–3). 無線局運用規則 (Radio Station Operation Regulations), Appended Table No. 1: Morse codee-Gov, Digital Agency of Japan. 別表第一号 (Article 12): 和文, 欧文, 数字の略体. Morse codeWikipedia (en). Characters and prosigns; Diacritics and non-Latin extensions; Cut numbers. SOSWikipedia (en). Signal, 1906 Berlin convention.	Normative: the table is the standard’s own	2026-10-13
American Morse	American Morse codeWikipedia (en). Comparison of American and International Morse; Common punctuation. American Morse CodeStephen C. Phillips, morsecode.world. Table and timing paragraph. The Art and Skill of Radio-Telegraphy, chapter 20William G. Pierpont, N0HFF. American Morse: lengths of L and 0, internal spaces.	Medium: the references differ on a few signs	2026-10-13
Russian Morse	Азбука МорзеВикипедия (ru). Таблица кодов. Morse code for non-Latin alphabetsWikipedia (en). Greek; Cyrillic.	High: two independent references agree	2026-10-13
Greek Morse	Κώδικας ΜορςΒικιπαίδεια (el). Αλφάβητο, Δίφθογγοι. Morse code for non-Latin alphabetsWikipedia (en). Greek; Cyrillic.	Medium: the references differ on a few signs	2026-10-13
Wabun	無線局運用規則 (Radio Station Operation Regulations), Appended Table No. 1: Morse codee-Gov, Digital Agency of Japan. 別表第一号 (Article 12): 和文, 欧文, 数字の略体. Wabun codeWikipedia (en). Prosigns DO and SN.	Normative: the table is the standard’s own	2026-10-13

§ 2Facts, words and timing

The letter pages, the numbers and the trainer also use these references. Each was checked on the date shown.

English Letter Frequency Counts: Mayzner RevisitedPeter Norvig. Letter Counts (Google Books, 3.56 trillion letters), 2012. Used for: how often each letter appears in English; checked 2026-10-13.
LCWO.net source code, $kochcharFabian Kurz, DJ5CW (LCWO.net). inc/functions.php, the Koch lesson order. Used for: the order in which the trainer teaches signs; checked 2026-10-13.
NATO phonetic alphabetWikipedia (en), after ICAO Annex 10 and ITU Radio Regulations Appendix 14. Code words; the ICAO spellings Alfa and Juliett. Used for: the spelling word of each letter; checked 2026-10-13.
A Standard for Morse Timing Using the Farnsworth TechniqueJon Bloom, KE3Z, ARRL Laboratory (QEX, April 1990). Equations for character speed c and overall speed s. Used for: Farnsworth timing in the trainer; checked 2026-10-13.
Recommendation ITU-R M.1172: Miscellaneous abbreviations and signals to be used for radiocommunications in the maritime mobile serviceInternational Telecommunication Union. Section I (Q code) and Section II (abbreviations). Used for: Q codes and abbreviations of the maritime service; checked 2026-10-13.
The ARRL Operating Manual for Radio AmateursAmerican Radio Relay League. Morse code (CW) chapter: abbreviations, prosigns and Q signals. Used for: abbreviations, prosigns and Q signals in amateur use; checked 2026-10-13.
RSGB Amateur Radio Operating ManualRadio Society of Great Britain. CW operating: abbreviations and procedure. Used for: abbreviations and CW procedure; checked 2026-10-13.
Q SignalsAmerican Radio Relay League. Q signals in amateur use. Used for: Q signals on the amateur bands; checked 2026-10-13.
SOSWikipedia (en). Signal, 1906 Berlin convention. Used for: the SOS signal and its history; checked 2026-10-13.

§ 3Found an error?

If a table disagrees with its source, or a source has changed since the date shown, write to the editor. Name the table, the sign and the source you compared it with, for example: “Greek, Ψ, Wikipedia (el), table of the alphabet.”

Write about an error · contact@morsealphabet.net