What is three dots and a dash in morse code?
Three dots and a dash is the letter V. It is three dits, the short signal, followed by one dah, which lasts three times as long. The four marks add up to six units of sound.
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Three dits and a dah, with a one-unit gap between each pair. The dah is drawn three times as long as a dit because that is exactly how long it sounds.
The four marks of V
ITU-R M.1677-1 sets one pattern per character, and V is three dits then a dah. The drawing above holds the real proportions: each dit is one unit wide, the dah is three units long, and the gaps between them are one unit each. Counted end to end, V is nine units, of which six are sound and three are silence.
At 20 words per minute (WPM) a unit is 60 milliseconds, so the whole letter takes 540 milliseconds to send. At 5 WPM the same letter runs to 2.16 seconds.
Telling V apart from its neighbors
Three of the characters people confuse with V start the same way, and only the ending differs:
- S is three dits and stops there
- H is four dits
- V is three dits and a dah
- the digit 4 is four dits and a dah
- the digit 5 is five dits
Heard rather than read, the difference is easy: S ends short, V ends long. That is why operators learn the sounds rather than counting marks on a page. Play the letter above, then open the morse code translator and listen to S and H next to it.
Three dots and a dash is not SOS
The pattern people most often mean when they describe dots and dashes in threes is SOS, which is three dits, three dahs and three dits. It is not the same thing as V, and it is not really three letters either.
The International Telecommunication Union’s record of the Berlin conference of 1906, which adopted the signal, writes it as one group of nine marks. There is no letter gap inside it, so a receiving operator hears one long run rather than S, then O, then S. Our SOS page plays it that way and shows how to blink it with a flashlight.
Where to see the rest of the table
Every letter, digit and punctuation mark sits on one sheet in the printable morse code chart, drawn at the same true proportions as the letter above, in color or in an ink-saver version for a black and white printer.
Questions people ask next
What letter is three dots and a dash?
V. It is the only character in ITU-R M.1677-1 built from three dits followed by one dah.
What is three dots in morse code?
The letter S, on its own. Add a fourth dit and it becomes H; add a dah instead and it becomes V.
What is three dots and three dashes and three dots?
The SOS distress signal, sent as one run of nine marks with no letter gaps inside it. Sent with the gaps, the same marks read as the three letters S, O and S.
What is four dots and a dash?
The digit 4. The digits all run to five marks, and 4 is four dits then one dah.
How long does V take to send?
Nine units in all: six units of sound and three one-unit gaps. That is 540 milliseconds at 20 words per minute.
Related answers
- What is a single dot in morse code?
A single dot is the letter E.
- What do 7 dots mean in morse code?
Nothing on its own.
- Does morse code have spaces?
Yes, three of them, and they carry as much as the marks do.
Sources
- Codes and timing follow Recommendation ITU-R M.1677-1 (10/2009), International Morse code (International Telecommunication Union, 2009).
- International Radiotelegraph Conference (Berlin, 1906) (International Telecommunication Union).