Morse (Vail) Code



Alfred Vail source
(1807-1859)


Samuel F. B. Morse source
(1791-1872)

References:

Modern International Morse Code reference

Letters

Letter Code Letter Code
A *- N -*
B -*** O ---
C -*-* P *--*
D -** Q --*-
E * R *-*
F **-* S ***
G --* T -
H **** U **-
I ** V ***-
J *--- W *--
K -*- X -**-
L *-** Y -*--
M -- Z --**

Numbers

 0  -----   
 1  *----
 2  **---
 3  ***--
 4  ****-
 5  *****
 6  -****
 7  --***
 8  ---**
 9  ----*
Common punctuation

 Period         *-*-*-  
 Comma          --**--
 Question Mark  **--**
 Double Dash    -***-
 Hyphen         -****-
 Fraction Bar   -**-*

Prosigns
 AR  *-*-*  Stop (end of message),often written +
 AS  *-***  Wait (for 30 s - 60 s), respond with C (yes)
 K   -*-    Invitation to transmit
            (normally follows AR to indicate 'back-to-you')
 SK  ***-*- End (end of contact), sometimes written VA
 BT  -***-  Separator, sometimes written =

Not really prosigns, an error may be indicated by any of: 

 VE  ***-*     I will send the last word again
     ** **     (same)
     ********  Error
Timing
  • A dah (dash) is conventionally 3 times as long as a dit (dot).
  • Spacing between dits and dahs in a character is the length of one dit.
  • Spacing between letters in a word is the length of a dah (3 dits).
  • Spacing between words is 7 dits.
Statistics reference

Alfred Vail's 1844 version of the code averaged 7.978 units per letter
(the minimum is 4 units per letter, the letter "e")


This page was prepared and is maintained by R. Victor Jones
Comments to: jones@deas.harvard.edu.

Last updated November 1, 2005