5 in Morse code

• S:

  ..., three dots.

• H:

  ...., four dots.

• The digit 5:

  ....., five dots.

At 18 words per minute a dot lasts about 67 ms, so the difference between H and 5 is a single blip of sound. Counting fails at speed; hearing the length of the whole buzz works. The Sound-alike drill is built for exactly this kind of pair.

The ten digits follow one rule: five elements each, with 1 to 5 opening with dots and 6 to 0 opening with dashes. 5 is where the dots run out, five of them and no dash at all.

0 is its exact opposite, -----, five dashes and no dot. Between them sit the mixed digits, so 4 is ....- and 6 is -...., each one step from 5.

Radio operators hear 5 most at the front of a signal report. In the RST system the first figure is readability, and 5 means perfectly readable; 599 adds the top marks for strength and tone. In contests the nines are cut to N, so 599 goes out as ..... -. -., written 5NN.

The cut-number table also lists E, a single dot, as a short form of 5, but 5 is often sent in full, as 5NN shows. More operating shorthand is on the abbreviations page.

• Tap it:

  five quick, even taps. At 18 words per minute the whole 5 lasts 9 units, about 600 ms.

• Flash it:

  as light it takes longer, because this site never flashes faster than 7 words per minute, so 5 takes about 1.5 seconds as a light signal.

• Write it:

  five periods with no spaces, then a space before the next character. The translator reads it back as 5.