The ARRL has adopted the following standard for all training material, code tests, and W1AW Morse transmissions:

  • A single dot is one unit.
  • A dash is a period of three units.
  • One unit separates each element (dot or dash) within a character.
  • Three units separate each character within a word.
  • Seven units separate each word.

This graphic depicts properly spaced Morse code timing.

A STANDARD FOR MORSE CODE SPEED:
For purposes of determining code speed, the โ€œPARISโ€ 5ร˜-unit standards is used. The word PARIS contains 5ร˜ units comprised of dots, dashes, intra character, inter character, and word spaces. Code speed in Words Per Minute (WPM) is derived by counting the number of times โ€œPARISโ€ is sent in one minute.

THE HARMONIC ORIGINS OF MORSE CODE:
In his book, “The CW Way of Life”, Chris Rutkowski NW6V explores the harmonic origins of Morse code. According to Chris, the original American Morse invented by Samuel Morse and Alfred Vail did not have a 3:1 ratio. It wasnโ€™t until Friedrich Gerke, a linguist and musician, modified American Morse in 1848 to meet the needs of the German language for the German Post Office that a 3:1 ratio was established.

Below we see the 3:1 ratio. A dit is one unit and a dah three units. Also, one unit separates each element within a character, and three units separates each character within a word. It is less obvious why seven units separates each word.

Below, Chris illustrates the logic of seven-unit separation between words. By sliding the origin of the graph a half-dit to the left, so it starts with the hand and key 90 degrees prior to contact one may visualize the nominal motion of the hand maps perfectly to the ON and OFF states of the signal. They always align because they are in-phase. The blue line reflects the inherent rhythm of Morse code.

The region above the centerline signifies KEY CONTACTS OPEN and below centerline it signifies KEY CONTACTS CLOSED. This correlates to the motion and state of hand up and hand down.