All About Morse Code Signals and Telecommunications

Written by UPrinting    ●    Updated on November 05, 2023


morse code as a way of communication

Before the 1800s, if you needed to communicate with someone who wasn't standing next to you, you typically had two options: You could go see them in person, or you could mail them a letter. But in the 1830s, Samuel F.B. Morse invented two things that revolutionized how people communicated. The first was the electrical telegraph, which he refined with the help of Alfred Vail. The second was Morse code.

With Morse code, messages could be sent through wires using pulses of electricity, allowing people to communicate almost instantly between any two places that were connected to the telegraph system. Telegraph networks rapidly expanded throughout the rest of the 1800s, enabling the faster spread of information across the country and around the world. The development of wireless telegraphy in the 1890s, thanks to Guglielmo Marconi, even allowed for telegraphs to be used by ships at sea. And all of these messages were sent using Morse code.

Morse code is a system in which each letter, number, or piece of punctuation is translated into a sequence of short and long pulses, called dots and dashes. Dots are short signals, and dashes are as long as three dots. Morse code was developed by examining the frequency of letter use in printed English texts and assigning sequences of dashes and dots based on how commonly used each character was. For instance, E is the shortest, easiest character to transmit in Morse code, using just a single dot, because E is the most common letter used in English.

The earliest telegraph machines etched the messages they received onto paper tape, which would then need to be decoded by the telegraph operator. However, operators soon realized that it was quicker and simpler to just listen to the clicking of the telegraph machine as the message came in and decipher the code by sound. They would often refer to what they heard as "dits" (dots) and "dahs" (dashes). The operator would transcribe the message as they heard it, and it would then be delivered by hand to the recipient.

Perhaps the most well-known piece of Morse code today is the code for "SOS." SOS was approved as the international code for a distress signal in 1906. This sequence of letters was chosen simply because it was easy to transmit, remember, and recognize: "S" is three dots, and "O" is three dashes, so the resulting sequence would be "dot dot dot, dash dash dash, dot dot dot." SOS did not originally stand for anything, but people later associated it with the phrase "save our ship."

The use of SOS was slow to spread at first; the Titanic, which sank in 1912, sent out both "SOS" and "CQD," an older distress call. However, after the Titanic sank, SOS became the universal international distress signal, a role it kept until 1999. In that year, the Global Maritime Distress and Safety System was adopted, replacing radio transmissions of distress calls with automated signals sent by satellite.

Today, SOS is still understood by most people as shorthand for a call for help, and Morse code is also still in use, though mostly by amateur radio operators. One benefit of using Morse code, even today, is that you can make Morse code in a variety of ways: Anything you can turn on and off, like a flashlight, can be used to communicate in Morse code, and you can also write messages in Morse code with many things, from beads on a string to printed dots and lines to sticks and rocks.

Meanwhile, the device once commonly used to transmit Morse code, the telegraph, became obsolete. The emergence of the telephone ultimately spelled the death of the telegraph, especially once phone calls became cheaper than telegrams in the mid-1900s.



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