Instruct: Given a question, retrieve relevant documents that answer the question.
Query: When was Morse Code created?
Morse code has been in use for more than 160 years—longer than any other electrical coding system. What is called Morse code today is actually somewhat different from what was originally developed by Vail and Morse. The Modern International Morse code, or continental code, was created by Friedrich Clemens Gerke in 1848 and initially used for telegraphy between Hamburg and Cuxhaven in Germany. Gerke changed nearly half of the alphabet and all of the numerals, providing the foundation for the modern form of the code. After some minor changes, International Morse Code was standardized at the International Telegraphy Congress in 1865 in Paris and was later made the standard by the International Telecommunication Union (ITU). Morse's original code specification, largely limited to use in the United States and Canada, became known as American Morse code or railroad code. American Morse code is now seldom used except in historical re-enactments.
Although Q codes were created when radio used Morse code exclusively, they continued to be employed after the introduction of voice transmissions. To avoid confusion, transmitter call signs are restricted; no country is ever issued an ITU prefix starting with "Q". 
Morse code was used as an international standard for maritime distress until 1999 when it was replaced by the Global Maritime Distress Safety System. When the French Navy ceased using Morse code on January 31, 1997, the final message transmitted was "Calling all. This is our last cry before our eternal silence."[22] In the United States the final commercial Morse code transmission was on July 12, 1999, signing off with Samuel Morse's original 1844 message, "What hath God wrought", and the prosign "SK".[23]
The "Tree of Transmission" is a visual representation of the Underland equivalent of Morse code, i.e. a method of transmitting information over long distances using repeating patterns. The code has no official name, as it is the only code to have been created by humans, rats, mice, spiders, crawlers, and bats together. It is very similar to Morse code, but with a few important differences. The first is that it is only transmitted with sound, usually through the stone of underground tunnels, while Morse code can also be used by switching a source of light or electricity on and off. This is because of the code's use of three distinct sounds (a "click", a "scratch", and a "tap"), while Morse code differentiates symbols only through the length of transmission. The other main difference from the Overland code is the lack of number symbols.
Morse is still widely used by amateur radio operators (hams). Experienced hams routinely send Morse at 20 words per minute, using manually operated hand telegraph keys; enthusiasts such as members of The CW Operators' Club routinely send and receive Morse code at speeds up to 60 wpm. The upper limit for Morse operators attempting to write down Morse code received by ear using paper and pencil is roughly 20 wpm. Many skilled Morse code operators can receive Morse code by ear mentally without writing down the information at speeds up to 70 wpm. To write down the Morse code information manually at speeds higher than 20 wpm it is usual for the operators to use a typewriter or computer keyboard to enable higher speed copying.
Morse code is called the original digital mode. Radio telegraphy, designed for machine-to-machine communication is the direct on/off keying of a continuous wave carrier by Morse code symbols, often called amplitude-shift keying or ASK, may be considered to be an "amplitude modulated" mode of communications, and is rightfully considered the first digital data mode.. Although more than 140 years old, bandwidth efficient Morse code, originally developed by Samuel Morse and Alfred Vail in the 1840s, uses techniques that were not more fully understood until much later under the modern rubrics of "source coding" or "data compression". The bandwidth efficiency of Morse code arises because the most used source symbols were accorded the shortest Morse code symbols and the least used were accorded the longest symbols by Vail and Morse. Vail and Morse intuitively understood bandwidth efficiency in code design. It was not until one hundred years later that Claude Shannon's modern information theory (1948) put Morse and Vail's Morse code technology on a firm theoretical mathematical footing, that then resulted in similar Morse code-like bandwidth efficient data encoding technologies such as the modern Huffman, Arithmetic and Lempel-Ziv codes. Morse code is still used by amateur radio operators. Operators may either key the code manually using a telegraph key and decode by ear, or they may use computers to send and receive the code.Decades after the advent of digital amplitude-shift keying (ASK) of radio carriers by Morse symbols, radio technology evolved several methods of analog modulating radio carriers such as: amplitude, frequency and phase modulation by analog waveforms. The first such analog modulating waveforms applied to radio carriers were human voice signals picked up by microphone sensors and applied to the carrier waveforms. The resulting analog voice modes are known today as:
ACP-131 CW Operators' Club Guglielmo Marconi High-speed telegraphy Hog morse Instructograph Morse code abbreviations Morse code mnemonics NATO phonetic alphabet Tap code Alfred Vail Wabun code Wireless telegraphy Theodore Roosevelt McElroy
A few competitions have been held between expert Morse code operators and expert SMS users.[165] Several mobile phones have Morse code ring tones and alert messages. For example, many Nokia mobile phones have an option to beep "S M S" in Morse code when it receives a short message. Some of these phones could also play the Nokia slogan "Connecting people" in Morse code as a message tone.[166] There are third-party applications available for some mobile phones that allow Morse input for short messages.[167][168][169]
To make Morse code communications faster and more efficient, there are many internationally agreed patterns or conventions of communication which include: extensive use of abbreviations, use of brevity codes such as the RST code, Q code, Z code as well as the use of Morse prosigns. The skills required to have efficient fast conversations with Morse comprise more than simply knowing the Morse code symbols for the alphabet and numerals. Skilled telegraphists must also know many traditional International Morse code communications conventions.
In 1886 and 1887, when the Royal E. House telegraph company was producing the printing telegraph, the Morse Telegraph company tried to enjoin (legally prevent) them from infringing on the Morse patents. Morse claimed the sole right of transmitting intelligence by electricity, utilizing the Morse code. The courts decided the House Company did not infringe the Morse patent, as the messages using the House system were all printed on a slip of paper, without the use of Morse Code.
Wyn Evans' firework pieces, for example, are wooden structures that spell out open-ended texts that burn over a designated period of time. His transparent, crystal chandelier sculptures, such as the multi-coloured Italian Murano glass chandelier‚ "Astrophotography..." (2006) are programmed to evoke an otherworldly language from sections of text translated into the flashing light signals of Morse Code. The texts rendered in code are sometimes visible simultaneously on adjacent computer screens embedded in the gallery walls and represent a personal canon of literature and include letters, poems, philosophical extracts and short stories by writers ranging from Theodor Adorno, William Blake and Judith Butler to Brion Gysin, James Merrill and the Marquis de Sade. For the Venice Biennale in 2003, he created "Cleave 03", an installation which consisted of a World War II searchlight sending a seven-mile beam of light into the night sky over the Giudecca flashing intermittently in a morse code version of Ellis Wynne's 1703 Welsh text "Gweledigaethau y Bardd Cwsc". In his earlier Cleave installations, he refracted the light signals of Morse code off a rotating mirror ball to create dazzling and intense sensory environments. The artist is also interested in the way that soundtracks form a parallel 'text' for a film or photograph and in the slippage created when these sounds are dislodged, changed or removed.
"Rag chewer" is a name applied to amateur radio Morse code operators who engage in informal Morse code conversations (known as "chewing the rag") while discussing subjects such as: the weather, their location, signal quality, and their equipment. Meaningful rag chewing between fluent Morse code operators having different native languages is possible because of a common language provided by the prosigns for Morse code, the International Q code, Z code, RST code, the telegraph era Phillips Code and many well known Morse code abbreviations as discussed in this Wikipedia article. Together all of these traditional conventions serve as a somewhat cryptic but commonly understood language (Lingua Franca) within the worldwide community of amateur radio Morse code operators.
The following Table of Morse code abbreviations and further references to Brevity codes such as the Q code, Z code and R-S-T system serve to facilitate fast and efficient Morse code communications.
Morse Code, when transmitted essentially, creates an AM signal (even in on/off keying mode), assumptions about signal can be made with respect to similarly timed RTTY signalling. Because Morse code transmissions employ an on-off keyed radio signal, it requires less complex transmission equipment than other forms of radio communication.
Over the years radioteletype was improved and computerized, giving rise to new digital transmission modes such as Clover and PACTOR. Satellite communications became a technically and commercially viable alternative to terrestrial radio links. Ship radio equipment became more advanced and automated, requiring fewer radio officers - or none. By the 1990s few ship stations were equipped for Morse code or had any use for it, so coast stations re-allocated their Morse frequencies to other uses. Some stations disappeared from the airwaves altogether, as did KPH after being acquired by Globe Wireless in 1997. Its Morse code traffic was then diverted to other stations such as KFS in Half Moon Bay, California, another Globe Wireless station. KFS continued to handle Morse code traffic until July 13, 1999 (Universal time; actually July 12 in the Pacific time zone) when it made its "last ever" Morse transmission, ceremonially marking the supposed end of commercial Morse code usage in America (as distinct from amateur Morse code usage, which continues). This anniversary is commemorated on the air every July as the "Night of Nights" by KPH and other coast radio stations, along with radio amateurs who participate on their own frequencies.
In the original Morse telegraphs, the receiver's armature made a clicking noise as it moved in and out of position to mark the paper tape. The telegraph operators soon learned that they could translate the clicks directly into dots and dashes, and write these down by hand, thus making the paper tape unnecessary. When Morse code was adapted to radio communication, the dots and dashes were sent as short and long tone pulses. It was later found that people become more proficient at receiving Morse code when it is taught as a language that is heard, instead of one read from a page.[15]
The current from the telegraph line is applied to the coil. The pulses of current representing the Morse code "dots" and "dashes" flowing through the coil create a magnetic field which interacts with the magnetic field of the magnet, creating a torque which causes the coil to rotate slightly about its vertical suspension axis. The wire linkages cause the siphon support plate to rotate about its horizontal axis, swinging the siphon tube across the paper tape. This draws a displacement in the ink line on the tape as long as the current is present in the coil. Thus the ink line on the tape forms a graph of the current in the telegraph line, with displacements representing the "dots" and "dashes" of the Morse code. An operator knowing Morse code later translates the line on the tape to characters of the text message, and types them onto a telegram form.
Morse Code cannot be treated as a classical radioteletype (RTTY) signal when it comes to calculating a link margin or a link budget for the simple reason of it possessing variable length dots and dashes as well as variant timing between letters and words. For the purposes of Information Theory and Channel Coding comparisons, the word PARIS is used to determine Morse Code's properties because it has an even number of dots and dashes.
Hog-Morse was the tendency of inexperienced telegraph operators to make errors when sending or receiving in Morse code. It is so called after one example, "home" () becoming "hog" (), which is just a subtle error in timing. The term was current in the United States in the period when American Morse code was in use.
The relatively limited speed at which Morse code can be sent led to the development of an extensive number of abbreviations to speed communication. These include prosigns, Q codes, and a set of Morse code abbreviations for typical message components. For example, CQ is broadcast to be interpreted as "seek you" (I'd like to converse with anyone who can hear my signal). OM (old man), YL (young lady) and XYL ("ex-YL" – wife) are common abbreviations. YL or OM is used by an operator when referring to the other operator, XYL or OM is used by an operator when referring to his or her spouse. QTH is "location" ("My QTH" is "My location"). The use of abbreviations for common terms permits conversation even when the operators speak different languages.
American Morse Code — also known as Railroad Morse—is the latter-day name for the original version of the Morse Code developed in the mid-1840s, by Samuel Morse and Alfred Vail for their electric telegraph. The "American" qualifier was added because, after most of the rest of the world adopted "International Morse Code," the companies that continued to use the original Morse Code were mainly located in the United States. American Morse is now nearly extinct—it is most frequently seen in American railroad museums and American Civil War reenactments—and "Morse Code" today virtually always means the International Morse which supplanted American Morse.
At the Radiotelegraphic Convention meeting in London in 1912, the section of the Convention covering "Transmission of Radiograms" included the statement that "The signals to be employed are those of Morse International Code." Even after this, the original Morse Code continued to be used throughout much of the United States. American Morse remained the standard for U.S. landline telegraph companies, including the dominant company, Western Union, in part because the original code, with fewer dashes, could be sent about 5% faster than International Morse. American Morse also was commonly used for domestic radio transmissions on the Great Lakes, and along the Atlantic and Pacific coasts. However, International Morse predominated for ocean-going vessels, and many U.S. shipboard operators became skilled in transmitting both versions of the Code as needed.
In the season seven premiere "Mr. Monk Buys a House", it is presumed that Mitch also taught Natalie how to use Morse code. When Monk, Natalie, Stottlemeyer, and Disher visit Cassie Drake's house and Stottlemeyer and Disher start tapping messages to each other in Morse code on the door, Natalie chastises them, hinting that Mitch taught her Morse code. This comes in handy later in the episode: when Monk and Natalie are taken hostage by "Honest" Jake Phillips, Natalie sends up smoke signals in Morse code through the fireplace to call for help, due to a lack of other forms of communication.
The use of Morse code is over a century old. Fluent Morse code telegraphers still enjoy sending Morse code using manually operated mechanical keys or electronic keyers. Although Morse code is no longer used in commercial practices, the use of hand-sent Morse code seems to be growing among amateur radio operators, even though Morse proficiency is no longer required to obtain an amateur radio licence.
In the following example of a typical casual Morse code conversation between two stations there is extensive use of such: Morse code abbreviations, brevity codes, Morse procedural signs, and other such conventions.