R in Morse Code

How long R takes

R is 2 dots and 1 dash. With the gaps that comes to 7 units, number 10 of 26 by length.

• 5 WPM: 1,680 ms
• 13 WPM: 646 ms
• 20 WPM: 420 ms

The arithmetic behind them is on the timing page.

What R gets confused with

5 characters sit one element away from R, more than most letters manage:

• A .- - the last dot missing
• G --. - a dash in first place instead of a dot
• L .-.. - one more dot on the end
• S ... - a dot in second place instead of a dash
• W .-- - a dash in third place instead of a dot

R in the tree

• Built from: . = E and .- = A, then .-.
• Carries on into: L (1 of the 26)
• Backwards: .-. = itself, a palindrome
• Koch position: 3 of 26

The tree shows the whole shape, the trainer teaches it by ear.

Why R has this code

R makes up about 6 per cent of English text, which is number 9 of 26 by frequency, against number 10 by length. Close enough that the code is doing its job for this letter.

The lengths were set by counting, not by theory - the alphabet page has that story.

R in American Morse

The American code, used on the landline telegraph until the 1920s, wrote R as . .. instead of .-.. Note the gap inside the character: American Morse used internal spaces, which is what made it so hard to read automatically and why the international code replaced it on the radio.

The full table has the other ten.

Worth knowing about R

R is the acknowledgement: "received, understood". It is also the R in an RST report, where it stands for readability.