50 free Morse Code trivia questions with answers — technology quiz, new questions added Aug 2026.
This Morse code trivia quiz covers the two-tone alphabet from Samuel Morse's 1844 telegraph line to its afterlife on the amateur bands. The easy questions are ones anyone could answer: what the dots and dashes are called, which letter is a single dit, what the famous distress call is, and the message that opened the Baltimore–Washington line. The harder end is for radio hams and history buffs: how long a dah lasts compared with a dit, how Alfred Vail worked out English letter frequencies, the German who rewrote half the alphabet, the 1865 Paris convention, why SOS was chosen and what it never stood for, the call the Titanic sent first, the standard word PARIS, Ted McElroy's 75.2 words per minute, the Vietnam POW who blinked TORTURE, why V sounds like Beethoven, the year the FCC dropped the code test, and the last words of the French Navy in Morse. Aviation beacons, prosigns and the Nokia SMS tone get questions too. Every answer was checked against encyclopaedia entries for the code, its inventors and its famous uses before publishing, and the supporting sentence is stored with each question. If you enjoy this one, try our Samuel Morse, inventions and Titanic quizzes next.
30 of 50 questions with answers and explanations. Play the quiz
Q 01What are the two signal elements of Morse code called?
Dits and dahs
They are also written as dots and dashes.
Q 02A dah lasts how many dit-lengths?
Three
The gap between letters is three dits.
Q 03How many dit-lengths of silence separate words in Morse code?
Seven
Letters within a word are separated by a three-dit space.
Q 04Which letter of the alphabet is a single dit in Morse?
E
As the most common English letter it was given the shortest code.
Q 05Who developed the alphabet-based code that replaced Samuel Morse's original proposal?
Alfred Vail
Morse had planned a very different scheme using a codebook.
Q 06How did Morse's engineer estimate how often each letter appears in English?
By counting a newspaper's movable type
He visited the type cases of a local paper in Morristown, New Jersey.
Q 07What had Samuel Morse originally planned to transmit instead of letters?
Only numerals
Each number would be looked up in a codebook to find the word.
Q 08At which family works in Morristown did Vail refine Morse's prototype telegraph?
Speedwell
He did it at his own expense in return for 25 percent of the proceeds.
Q 09Which German simplified Vail's code into the version adopted in Europe?
Friedrich Clemens Gerke
He created it in 1848 for the Hamburg–Cuxhaven telegraph and changed nearly half the alphabet.
Q 10In which city was International Morse Code standardised in May 1865?
Paris
The International Telegraph Convention finalised it after a complete revision of the numerals.
Q 11Which four letters kept their original Morse codes through all the revisions?
E, H, K, N
K and N had their short dahs lengthened to full length.
Q 12Which letter did Gerke's code not distinguish, requiring a new codepoint in 1865?
J
Gerke treated I and J as one letter.
Q 13What was Vail's original American version also known as?
Railroad Morse
US railroads largely phased it out by the mid-1950s.
Q 14What message officially opened the Baltimore–Washington line on 24 May 1844?
Q 21Which company's Circular 57 of 1904 made a three-letter distress call standard for its ships?
Marconi International Marine
Its call was never adopted internationally because it could be mistaken for a plain general call.
Q 22Which distress call did Titanic's Jack Phillips send first on 15 April 1912?
CQD
It was still commonly used by British ships in 1912.
Q 23How is the SOS prosign different from the three letters S, O and S?
It is keyed without gaps between characters
Its meaning is: this is the start of a distress message.
What hath God wrought
Morse sent it from the Supreme Court chamber in the basement of the Capitol.
Q 15How much did Congress appropriate in 1843 for the experimental Washington–Baltimore line?
$30,000
The 38-mile line ran along the Baltimore and Ohio Railroad right of way.
Q 16What news was telegraphed from Baltimore to the Capitol on 1 May 1844 in an early demonstration?
Henry Clay's Whig nomination
The official opening followed on 24 May.
Q 17What was Samuel Morse's profession before the telegraph?
Portrait painter
He co-developed the code in 1837 in his middle age.
Q 18Which country first adopted SOS as a distress signal, on 1 April 1905?
Germany
It called it the Notzeichen signal.
Q 19What did SOS originally stand for?
Nothing; it was just a distinctive sequence
The backronyms came later in popular usage.
Q 20When did SOS become a worldwide standard under the 1906 Berlin convention?
1 July 1908
The first International Radiotelegraph Convention signed the agreement on 3 November 1906.
Q 24Which two standard words are used to measure Morse speed in words per minute?
PARIS and CODEX
Speeds measured with the two words can differ by up to 20 percent.
Q 25Who set the still-standing Morse copying record of 75.2 WPM in 1939?
Theodore Roosevelt McElroy
The contest was held in Asheville, North Carolina.
Q 26What speed did Harry Turner reach with a straight key in 1942, the fastest ever sent that way?
35 WPM
Semi-automatic and electronic keyers allow much faster sending.
Q 27Which POW blinked the word TORTURE in Morse during a 1966 North Vietnamese TV appearance?
Jeremiah Denton
His captors did not notice the eye-blinks.
Q 28Which letter's Morse rhythm matches the opening of Beethoven's Fifth Symphony?
V
Churchill promoted the di-di-di-dah as V for Victory and the BBC played the phrase before broadcasts.
Q 29Which phrase is a mnemonic for the Morse letter Q, dah dah di dah?
God Save the Queen
Did she like it? is the mnemonic for F.
Q 30What replaced Morse as the international maritime distress standard in 1999?
The GMDSS
The US Coast Guard no longer monitors the 500 kHz Morse distress frequency.