Teletype, telex or TTY: what is it, what is it for and how does it work?

This German device reached its peak at the end of 1945 and has gained wide acceptance in postal companies of European governments in because of the practicality of implementing this system.

In this post, we will show you what a telex is and what it is for . In addition, we will talk about its origin and evolution to date and we will tell you who are the people who use this tool today .

We bring you all the information you need on an ATS. Read on to the end of this article and you'll find out all the details.

What is a teleprinter or TTY and what are these devices used for?

TTY or teleprinter is a device similar to a typewriter . It has an alphanumeric keyboard that manages to write messages for later sending. It also allows you to receive point-to-point typed messages, connected by a telegraph cable for later printing.

The most modern models use a screen on which you can print telephone communications. At present, this mechanism is obsolete, but it is used in people who have hearing problems so that they can get the phone conversation in printed form.

Origin

This device telegraph has its origin in Germany, in the mid-20s of the last century . It was used for the Reich postal service with which just over 60 words per minute could be transmitted. After the end of World War II, it was possible to expand to the whole world.

After more than 50 years of its creation , the postal services of the main European governments have launched shortwave radio links, the standard being "R.44" , belonging to "ITU Telecommunication Standardization Sector" . Where the data transmission has been performed by time division in time slices cyclically, thereby generating a set of bits.

The communication system he had was carried out in direct current . Where it is interrupted in a very similar way to dialing a landline, using a dot for the start and a line for the space, again ending with a dot to define a cycle.

Evolution and history

Most of these teletypes used the 5-bit code (called Baudot or ITA2) , which had a limit of 32 characters . Where, to enter special characters of numbers, exclusive keys must be used for them.

At first the teams used a little for starting and stopping, due to its electromechanical design. Over time, devices have become synchronous, often making the task of synchronizing their mechanical components difficult.

For this reason, it was decided to continue using the 5-bit Baudot code , where special versions have been created to be able to apply them in certain reports, such as weather reports.

The postal and telegraph services, which did not have significant economic resources, carried out their operations in the digital or telex channels radio to get more value from it. So, over time, the cost of this equipment has decreased significantly and from 2016, radio amateurs use this short wave system called RTTY .

How does a telex work to send and receive typed messages?

These equipments have a writing keyboard and a reception device for printing the reception of messages . Which are made through printed characters defined by electrical signals, which consist of different combinations of electrical impulses, positive and negative.

In this way, different characters are sent and they are interrupted according to an encryption predetermined by a standard. It is a system very similar to a fixed telephone numbering. Once the characters have reached the receiving telex, it begins printing them according to the standard assignment.

Telex vs Fax, which is better and how is it different?

While it is true that two devices have a similar physical appearance (considering the latest teletypes, since in their early days they were big and heavy) , the technological difference that exists in each of them is very great.

Given than with telex, messages can be sent and received via an integrated keypad , while with a fax also there is a messaging service, but images which are not supported by the first mechanical equipment can be incorporated.

Also, the texts generated in the fax are not created on the same device, but a separate text computer is required to get a written message.

In this way, we can conclude that a fax is much better today for sending and accepting messages than a telex. Indeed, not only can you send or receive texts, but you can also send different images or shapes of designs that can be scanned with special software and sent by email.

If you have any questions, please leave them in the comments, we will get back to you as soon as possible, and it will be a great help for more community members as well. Thank you!