from the birth of technology to modern times
Hello people of the future! Let’s delve a little into the past today: we’ll talk about the teletype. They have practically forgotten about him – I think it’s in vain. His contribution to the development of communications is enormous; perhaps without the teletype there would be no Internet.
Under the cut – we pay tribute to this invention and remember what the teletype has in common with teleprinters, what the Baudot code is, what the Morkrum Printing Telegraph looked like and what devices based on teletype technology were generally used for.
Where it all started
The teletype, or teleprinter, is a communications technology inextricably linked with its predecessor, the telegraph. The first telegraph devices using electric current to transmit messages appeared in the 30s of the 19th century. One of the first inventors of the electromagnetic telegraph was the Russian scientist Pavel Lvovich Shilling. He presented his system in 1832.
Unfortunately, it has not received widespread commercial implementation. Most likely, because after a year or two simpler and cheaper systems appeared. Thus, in Germany, Carl Gauss and Wilhelm Weber showed their inventions to the world in 1833. In the UK – Charles Cook and William Wheatstone in 1837. In the USA, the electromagnetic telegraph was patented by Samuel Morse in the same 1837.
Telegraph devices developed by Schilling, Gauss and Weber, as well as Cook and Wheatstone, were switch-type electromagnetic devices. But the Morse apparatus was electromechanical.
But let's get back to the teletype. One of the first examples of the use of the principles underlying this technology was became a printing telegraphcreated by an American inventor Royal Earl House in 1846. His system allowed printed messages to be transmitted through electrical wires using synchronization mechanisms similar to modern printers. Speed - almost 40 words per minute.
The technology gradually developed, and a key step in its further popularization was the contribution of Emil Bodo in France in 1874. He developed a telegraph apparatus that could transmit several messages at once in one direction over one wire. His invention and others based on this principle became known as start-stop. The unit of information transmission speed, the Baud, was named in honor of Baudot.
He also created a code that was called the “Bodot code”, then it became known as the International Telegraph Code No. 1 (ITA1). It used five bits to encode characters, and the code became the standard for telegraph systems around the world until the mid-20th century. The modified version of MTK No. 1 was called ITA2. In the USSR, based on ITA2, the telegraph code MTK-2 was developed.
Aaand… we have a teletype!
Further work on the start-stop telegraph apparatus created by Baudot led to the appearance of teleprinters (teletypes).
Why two names if they are essentially the same thing? When the technology emerged, the name “teleprinter” was used. But later the term “teletype” became more common, largely thanks to the Teletype Corporation: it produced such devices. That is, Teletype is actually a brand of teleprinter, but in everyday speech both names have become synonymous.
A teletype is an electromechanical device capable of transmitting and receiving printed messages via electrical or radio communication channels based on the code already mentioned.
The main feature of the teletype was use of punched paper tapes — paper tapes, perforated for encoding messages. The advantage of such a storage medium is durability and convenience for mass data transfer. Some teletype machines had the ability to read punched tapes and write new ones.
One of the first widespread devices was the Morkrum Printing Telegraph (early 20th century). This model allowed the transmitter and receiver to be synchronized, so that data exchange became more reliable.
In 1928, Morkrum was renamed Teletype Corporation. The company became the leading manufacturer of teleprinters in the United States, giving a new name to the entire technology, as discussed above. Spoiler: it was later acquired by AT&T.
Devices based on teletype technology
Teletype Model 14, year of appearance – 1925
This device has become one of the first mass-produced teletypes and a major tool in telegraph networks in the 1920s and 1930s. The system was based on Baudot code and used narrow perforated tapes to record messages. In the 1920s and 1930s it was the main instrument for telegraph systems.
Where and for what was the device used:
Countries: USA, UK, France.
Tasks: used to share information with financial and news outlets such as the Associated Press. In wartime – for the transmission of encrypted messages and strategic information between command posts. During the Second World War the device was a means of communication between headquarters and field units in the US and British armies.
Teletype Model 15, year of appearance – 1930
The Model 15 became the standard for international telegraph systems in the 1930s and 1940s. The device was improved: the typing speed was increased to 45 words per minute. The device supported both sending and receiving messages.
Where and for what was the device used:
Countries: USA, Germany, UK, France.
Tasks: The model was used in the international telegraph network, providing communications between government agencies, news outlets, and diplomatic missions. Countsthat during World War II, about 90% of messages transmitted via teletypes were related to military operations. The device was also used by railway companies to transmit schedules and cargo information.
Teletype Model 33 ASR, year of appearance – 1961
One of the first teletype models to be integrated with computers. Supported the ASCII standard for data transmission, a step in the standardization of computer communications.
Where and for what was the device used:
Countries: USA, UK, Canada, Japan.
Tasks: used in research organizations to connect early computers to networks. The device was used in commercial computing centers and government agencies to exchange data between PCs. The new systems were used by the military.
Inktronic Terminal, year of appearance – 1966
This is already a high-speed teletype, designed to work with telephone lines and radio. Device could transmit data at speeds of up to 1,200 characters per minute. One of the fastest models of its time.
Where and for what was the device used:
Countries: USA, Germany, USSR, UK.
Tasks: in the military sphere – for transmitting data to submarines and other objects. Such systems were installed in government agencies and large corporations for the rapid exchange of data around the world. In the USSR and Germany it was used in civil aviation and military communications systems for the exchange of information between air bases and headquarters.
K-37 “Crystal”, 1940s
K-37 “Crystal” — small-sized disk encoding machine. During World War II, Soviet troops used it for operational-tactical tasks. The device was still based on the Baudot code for transmitting encrypted messages over radio channels and telegraph lines. This is how the USSR managed to protect strategic information from interception by enemies. The device was quite difficult to hack in real time.
Where and for what was the device used:
Countries: USSR.
Tasks: The K-37 was used for military communications at the highest levels of command, including communications between Soviet headquarters and front lines. In the post-war years, it continued to be used for military communications in the USSR and the Warsaw Pact countries. Its ability to encrypt made it a key element of communications between the highest levels of military command.
The device served as a tool for protecting information during a period when interception and decryption of enemy communications could affect the outcome of major military operations.
What these days?
Teletypes are hardly used today, but the legacy of this type of communication lives on in modern technology. The basic principles of the teletype were used in the first computer terminals. This contributed to the development of text-based interfaces and operating systems – for example, Unix. The flow control concepts used in teletype machines are still used in computers today. A little about them:
CR (Carriage Return) returned the print head or teletype carriage to the beginning of the line. She moved along the line, typing symbols. At the end of a line, it had to be moved back to the starting position in order for the next line to be printed. This command is used in computers to do the same thing – move the cursor to the beginning of the line.
LF (Line Feed) moved the paper up one line to begin printing the next line below the current one. On computer systems, the LF command does the same thing—it moves the cursor down one line.
Teletype machines played a role in the creation of early computer networks and technologies for exchanging information between machines. Standardization of data transmission using ASCII codes made it possible to unify communications between different devices, and this led to the creation of modern computer networks and the Internet.
In general, the history of the teletype is the history of the evolution of communications. Teletypes paved the way for modern digital technology, from the first primitive telegraph machines to complex data exchange devices.
