Teleprinter

teletypeteletypewritertelexteletype machineTTYteletypesTeleTypeSetterTeletype machinesteletypewriterstelex machines
A teleprinter (teletypewriter, Teletype or TTY) is an electromechanical device that can be used to send and receive typed messages through various communications channels, in both point-to-point and point-to-multipoint configurations.wikipedia
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Electromechanics

electromechanicalelectro-mechanicalElectromechanical Engineering
A teleprinter (teletypewriter, Teletype or TTY) is an electromechanical device that can be used to send and receive typed messages through various communications channels, in both point-to-point and point-to-multipoint configurations.
Before the development of modern electronics, electromechanical devices were widely used in complicated subsystems of parts, including electric typewriters, teleprinters, clocks, initial television systems, and the very early electromechanical digital computers.

Telex

Telex IITeletypewriter eXchangeTWX
These included a simple pair of wires; dedicated non-switched telephone circuits (leased lines); switched networks that operated similarly to the public telephone network (telex); and radio and microwave links (telex-on-radio, or TOR).
The telex network was a customer-to-customer switched network of teleprinters similar to a telephone network, using telegraph-grade connecting circuits for two-way text-based messages.

Airline teletype system

communicationsIATA standard messagingtelecommunications
Teleprinters are still widely used in the aviation industry (see AFTN and airline teletype system), and variations called Telecommunications Devices for the Deaf (TDDs) are used by the hearing impaired for typed communications over ordinary telephone lines.
The airline teletype system uses teleprinters, which are electro-mechanical typewriters that can communicate typed messages from point to point through simple electric communications channels, often just pairs of wires.

Telecommunications device for the deaf

TDDTTYtelecommunications devices for the deaf
Teleprinters are still widely used in the aviation industry (see AFTN and airline teletype system), and variations called Telecommunications Devices for the Deaf (TDDs) are used by the hearing impaired for typed communications over ordinary telephone lines.
A telecommunications device for the deaf (TDD) is a teleprinter, an electronic device for text communication over a telephone line, that is designed for use by persons with hearing or speech difficulties.

Modem

modemsdial-up modem56k modem
A teleprinter attached to a modem could also communicate through standard switched public telephone lines.
Modems grew out of the need to connect teleprinters over ordinary phone lines instead of the more expensive leased lines which had previously been used for current loop–based teleprinters and automated telegraphs.

User interface

UIinterfaceweb interface
The machines were adapted to provide a user interface to early mainframe computers and minicomputers, sending typed data to the computer and printing the response.
The earliest command-line systems combined teleprinters with computers, adapting a mature technology that had proven effective for mediating the transfer of information over wires between human beings.

Frederick G. Creed

Frederick George CreedCreedtelegraphs
The teleprinter evolved through a series of inventions by a number of engineers, including Samuel Morse, Alexander Bain, Royal Earl House, David Edward Hughes, Emile Baudot, Donald Murray, Charles L. Krum, Edward Kleinschmidt and Frederick G. Creed. In 1924 Britain's Creed & Company, founded by Frederick G. Creed, entered the teleprinter field with their Model 1P, a page printer, which was soon superseded by the improved Model 2P.
He worked in the field of telecommunications, and is particularly remembered as a key figure in the development of the teleprinter.

Donald Murray (inventor)

Donald Murray
The teleprinter evolved through a series of inventions by a number of engineers, including Samuel Morse, Alexander Bain, Royal Earl House, David Edward Hughes, Emile Baudot, Donald Murray, Charles L. Krum, Edward Kleinschmidt and Frederick G. Creed.
Donald Murray (1865–1945) was an electrical engineer and the inventor of a telegraphic typewriter system using an extended Baudot code that was a direct ancestor of the teleprinter (teletype machine).

David Edward Hughes

David E. HughesHughesHughes telegraph
The teleprinter evolved through a series of inventions by a number of engineers, including Samuel Morse, Alexander Bain, Royal Earl House, David Edward Hughes, Emile Baudot, Donald Murray, Charles L. Krum, Edward Kleinschmidt and Frederick G. Creed.
In 1855, Hughes designed a printing telegraph system.

Punched tape

paper tapepunched paper tapepunch tape
Some models could also be used to create punched tape for data storage (either from typed input or from data received from a remote source) and to read back such tape for local printing or transmission.
Now effectively obsolete, it was widely used during much of the twentieth century for teleprinter communication, for input to computers of the 1950s and 1960s, and later as a storage medium for minicomputers and CNC machine tools.

Aeronautical Fixed Telecommunication Network

AFTNAeronautical Fixed Telecommunications Network
Teleprinters are still widely used in the aviation industry (see AFTN and airline teletype system), and variations called Telecommunications Devices for the Deaf (TDDs) are used by the hearing impaired for typed communications over ordinary telephone lines.
The original AFTN infrastructure consisted of landline teleprinter links between the major centers.

Charles L. Krum

Charles Krum
The teleprinter evolved through a series of inventions by a number of engineers, including Samuel Morse, Alexander Bain, Royal Earl House, David Edward Hughes, Emile Baudot, Donald Murray, Charles L. Krum, Edward Kleinschmidt and Frederick G. Creed.
Charles L. Krum was a key figure in the development of the teleprinter, a machine which played a key role in the history of telegraphy and computing.

Edward Kleinschmidt

Edward Ernst Kleinschmidt
The teleprinter evolved through a series of inventions by a number of engineers, including Samuel Morse, Alexander Bain, Royal Earl House, David Edward Hughes, Emile Baudot, Donald Murray, Charles L. Krum, Edward Kleinschmidt and Frederick G. Creed.
Edward Ernst Kleinschmidt (September 9, 1876 – August 22, 1977) was one of the inventors of the teleprinter, and was a prolific inventor who obtained 118 patents in the course of his 101-year life.

Radioteletype

RTTYradiotelexradio teletype
60 speed became the de facto standard for amateur radio RTTY operation because of the widespread availability of equipment at that speed and the U.S. Federal Communications Commission (FCC) restrictions to only 60 speed from 1953 to 1972.
Radioteletype (RTTY) is a telecommunications system consisting originally of two or more electromechanical teleprinters in different locations connected by radio rather than a wired link.

Western Union

Western Union Telegraph CompanyAmerican Telegraph CompanyWestern Union Telegraph
In less than two years, a number of small telegraph companies, including Western Union in early stages of development, united to form one large corporation – Western Union Telegraph Co. – to carry on the business of telegraphy on the Hughes system.
In 1914, Western Union offered the first charge card for consumers; in 1923 it introduced teletypewriters to join its branches.

Teletype Corporation

TeletypeMorkrum-Kleinschmidtteletypewriter
Instead of wasting time and money in patent disputes on the start-stop method, Kleinschmidt and the Morkrum Company decided to merge and form the Morkrum-Kleinschmidt Company in 1924.
Teletype Corporation, of Skokie, Illinois, was responsible for the research, development and manufacture of data and record communications equipment, but it is primarily remembered for the manufacture of electromechanical teleprinters.

Telegraphy

telegraphtelegramcable
Initially they were used in telegraphy, which developed in the late 1830s and 1840s as the first use of electrical engineering.
Traffic became high enough to spur the development of automated systems—teleprinters and punched tape transmission.

Friden Flexowriter

FlexowriterFlexowritersFriden
Other codes, such as FIELDATA and Flexowriter, were introduced but never became as popular as ITA2.
The Friden Flexowriter was a teleprinter, a heavy-duty electric typewriter capable of being driven not only by a human typing, but also automatically by several methods, including direct attachment to a computer and by use of paper tape.

Creed & Company

CreedBritish Creed
In 1924 Britain's Creed & Company, founded by Frederick G. Creed, entered the teleprinter field with their Model 1P, a page printer, which was soon superseded by the improved Model 2P.
Creed & Company was a British telecommunications company founded by Frederick George Creed which was an important pioneer in the field of teleprinter machines.

Émile Baudot

Emile BaudotBaudotBaudot, Emile
The teleprinter evolved through a series of inventions by a number of engineers, including Samuel Morse, Alexander Bain, Royal Earl House, David Edward Hughes, Emile Baudot, Donald Murray, Charles L. Krum, Edward Kleinschmidt and Frederick G. Creed.
The Telegraph Service encouraged Baudot to develop—on his own time—a system for time-multiplexing several telegraph messages using Hughes teleprinters.

Control character

control codenon-printing charactercontrol codes
The Murray code also introduced what became known as "format effectors" or "control characters" – the CR (Carriage Return) and LF (Line Feed) codes.
The bell character (BEL), which rang a bell to alert operators, was also an early teletype control character.

ASCII

US-ASCIIAmerican Standard Code for Information InterchangeASCII code
It prints nothing because the characters received are all zeros, the ITA2 blank (or ASCII) null character.
Its first commercial use was as a seven-bit teleprinter code promoted by Bell data services.

Asynchronous serial communication

asynchronousasynchronous start-stopstop bit
The ITA2 code was used asynchronously with start and stop bits: the asynchronous code design was intimately linked with the start-stop electro-mechanical design of teleprinters.
A common kind of start-stop transmission is ASCII over RS-232, for example for use in teletypewriter operation.

Teletype Model 33

Model 33teletypeTeletype Model 33 ASR
Later teleprinters, specifically the Teletype Model 33, used ASCII code, an innovation that came into widespread use in the 1960s as computers became more widely available.

Bit

bitsbinary digitbinary digits
Most teleprinters used the 5-bit International Telegraph Alphabet No. 2 (ITA2).
The encoding of text by bits was also used in Morse code (1844) and early digital communications machines such as teletypes and stock ticker machines (1870).