Posted on Leave a comment

How to communicate with Morse code (using visual, audio, and pressure forms of communication)

Morse code alphabet and numbers

About Morse Code

Early Morse code telegraph machineMorse code (not “Morris code”) is a method of transmitting textual messages using a series of patterns.  Each text unit in the pattern can be represented (or reproduced) using on-off tones (sound), flashing lights, or clicks representing “dots” and “dashes” (known as dits and dahs).  The traditional Morse code encodes the 26 Roman letters but extensions have been added to allow for representation of non-English languages and a small set of punctuation and procedural signals.

To improve efficiency and transmission speed, Morse code was designed so that the length of a character in Morse varies inversely with its frequency of use in the English language.  For example, the letter “E” is the most used character in the English language and is represented by the shortest possible Morse code – a single dot.

Interestingly, individual Morse code operators differ slightly, for example using slightly longer or shorter dashes or gaps, perhaps only for particular characters. This is called their “fist”, and experienced operators can recognize specific individuals by their fist alone. A good operator who sends clearly and is easy to copy is said to have a “good fist”. A “poor fist” is a characteristic of sloppy or hard-to-copy Morse code.

The History of Morse Code

Morse Code was developed by Samuel Morse and Alfred Vail in the early 1830s as a means of sending messages over long distances using telegraph technology. The development of the communication method was not an easy feat. In fact, Morse struggled for years to perfect his code and find a way to transmit messages over long distances. Finally, in 1843, Morse received funding from the U.S. Congress to build a telegraph line from Washington, D.C., to Baltimore, Maryland, and he and his assistant, Alfred Vail, were able to develop a practical system for transmitting messages using Morse code.

The first Morse code message was transmitted on May 24, 1844, from Washington, D.C., to Baltimore, Maryland. The message, “What hath God wrought,” was transmitted over a wire using a series of dots and dashes that represented letters of the alphabet.

Morse code quickly became the standard method of communication for telegraph operators throughout the world. It was used extensively during the American Civil War, and it played a key role in the development of radio communication in the early 20th century.

Ways to use Morse Code

Morse code using audio tones

Morse code can be transmitted in a number of different ways.  Originally designed to be used as an electrical pulse along a telegraph wire, it can easily be represented as an audio tone.  Used as an audio signal, Morse code can be transmitted via a radio signal with short and long tones or even the sound of a car horn.  In survival situations, Morse code can be produced via the banging of pots and pans or knocking loudly on a hollowed log.

Morse code using visual cues

Morse code is commonly transmitted as a visual signal using flashing lights or reflections but can also be used as a non-detectable form of communication using the tapping of fingers or even blinking of eyes.

Using just two states (on and off), it is a form of digital code and can also be represented using 1’s and 0’s.  For example, a Morse code sequence may be made from a combination of the following five-bit strings:

  1. short mark, dot or “dit” (·) : 1
  2. longer mark, dash or “dah” (–) : 111
  3. intra-character gap (between the dots and dashes within a character) : 0
  4. short gap (between letters) : 000
  5. medium gap (between words) : 0000000

Morse code using touch or pressure

Early Morse code telegraph machineFinally, Morse code can be transmitted using touch or pressure.  For instance, some miner rescues have used tugs of a rope as a means to transmit Morse code to an injured miner.

How to communicate using Morse Code

Each Morse code character is represented by a unique sequence of dots and dashes.  A dot (or dit) represents a single unit whereas a dash (or dah) is three times the duration of a dot.  Each dot or dash is followed by a short silence equal to one dot.  Letters in a word are separated by silence equal to three dots (one dash) and words are separated by seven dots of silence.

  1. Dot – one “dit”
  2. Dash – three dits or “dah”
  3. Space between letters – three dits of silence
  4. Space between words – seven dits of silence

Learning to receive Morse code

The easiest way to learn Morse code is to find Morse code recordings, listen to them, and work out the encoded message on paper.  While learning, do not get into the habit of counting the dots and dashes in the Morse code.  Instead, learn to recognize the sound of each letter. If using a software application that helps train you in Morse code, never slow down the letter speed but rather, only slow down the letter spacing.

A dichotomic search tree can be used as a means to improve speed too (see example in the gallery).  Using a dichotomic search tree, each time you hear a dit (short beep) you move down and to the left on the tree.  Each time you hear a dah (or long beep), you move down and to the right.  Practice with a dichotomic search tree can dramatically improve your Morse code transmission speed.

Another option when receiving Morse code is to simply jot down the dots and dashes and then use a chart (download below) to decode the Morse code message.  “Pros” however, will point out that this effectively doubles the time it takes to decode the message.

Learning to transmit Morse code

Practicing Morse code can be done in your head or using the buttons on a smartphone device to produce audio Morse code tones.  Pick a word you wish to transmit and hear the sound in your head.  Dit is pronounced “di” with a short “I” and silent “T”.  Dah is pronounced with a short “A” sound.  Thus, “cat” would be pronounced dah-di-dah-di  di-dah  dah.  Again, hear the code in your head.  The letter “C” in cat sounds like dah-dit-dah-dit (long short long short).  In Morse code, cat would look like this:

Morse code example - cat

When transmitting, pay particular attention to your spacing.  Each letter should be separated by a space equal to the same duration as a dah (three times the duration of a dit).  Each word should be separated by a space that lasts about seven times the duration of a dit.  The better your spacing, the easier your code will be to understand.

Morse code tips

It helps to know the number of dits and dahs in each letter.  This will help you narrow down the possibilities when you receive a Morse code encoded message.

T, E= 1 character each

A, I, M,N= 2 characters

D, G, K, O, R, S, U, W= 3 characters

B, C, F, H, J, L, P, Q, V, X, Y, Z= 4 characters each

Morse code examples

Below are Morse code examples which may help you visualize the encoding/decoding of Morse code into its textual representation.


Morse code example - dog


Morse code example - survival


Morse code example - SOS

Need water

Morse code example - need water

Taking fire

Morse code example - taking fire

Danger ahead

Morse code example - danger ahead

Basic Morse code table

The chart below contains the complete International Morse code.  Downloadable versions of the chart are available in the gallery below.  In the charts, a dash is equal to three dots in time, while the interval between the dots and dashes in a letter equals a dot in time.  Between the letters in a word the interval is equal to three dots and between words, five dots.

Morse code alphabet and numbers
Morse code abbreviated numbers, punctuation, and other signs

Morse code Q-Codes

Q-codes are standard three-letter message encodings often used in Morse code communication.

Morse code Q-Codes

Morse code phrases

Other abbreviations are commonly accepted in Morse code communications including the list below.

Morse code phrases

Gallery of Morse Code charts

Below is a gallery of Morse code charts.  Click the diagram and then right click to save a copy.

  • Morse Code Chart to Download
  • 2560px International Morse Code letters.svg
  • image thumb109
Leave a Reply

Your email address will not be published. Required fields are marked *