Telegraph apparatus: types, scheme and photos

Telegraph apparatus played a great role in the formation of modern society. Slow and unreliable transmission of information slowed progress, and people were looking for ways to speed it up. With the invention of electricity, it became possible to create devices that instantly transmit important data over long distances.

At the dawn of history

Telegraph in different incarnations is the oldest type of communication. Even in ancient times, there was a need to transmit information at a distance. For example, in Africa, tomtama drums were used to transmit various messages, in Europe - a fire, and later - semaphore communication. The first semaphore telegraph was first called a "tachigraph" - a "scribe", but then replaced it with a more appropriate designation by the name "telegraph" - "long-distance".

The first apparatus

With the discovery of the phenomenon of electricity and especially after the remarkable studies of the Danish scientist Hans Christian Oersted (the founder of the theory of electromagnetism) and the Italian scientist Alessandro Volta, the creator of the first galvanic cell and the first battery (it was then called the "volt pole"), many ideas for creating an electromagnetic telegraph .

Attempts to manufacture electrical devices that transmit certain signals over a certain distance have been made since the end of the 18th century. In 1774 the simplest telegraph apparatus was built in Switzerland (Geneva) by the scientist and inventor Lesage. He connected the two transceivers with 24 isolated wires. When a pulse was applied by an electric machine to one of the wires of the first device on the second, the rubber ball of the corresponding electroscope deviated. Then the technology was perfected by the researcher Lomon (1787), who replaced 24 wires per one. However, this system can hardly be called a telegraph.

Telegraphic devices continued to improve. For example, the French physicist André Marie Ampere created a transmitter, consisting of 25 magnetic arrows suspended from the axes, and 50 wires. True, the bulkiness of the device made such a device almost useless.

The Schilling apparatus

In Russian (Soviet) textbooks it is pointed out that the first telegraph apparatus, differing from its predecessors by efficiency, simplicity and reliability, was designed in Russia by Pavel L. Schilling in 1832. Naturally, some countries dispute this assertion by "promoting" their no less talented scientists.

The works of PL Schilling (many of which, unfortunately, have not been published) in the field of telegraphy contain many interesting projects of electric telegraph apparatus. The device of Baron Schilling was equipped with keys that switched the electrical current in the wires connecting the transmitting and receiving apparatus.

The world's first telegram, consisting of 10 words, was transmitted on October 21, 1832, from a telegraph apparatus installed in the apartment of Pavel L. Shilling. The inventor also developed a cable laying project to connect telegraph units along the bottom of the Gulf of Finland between Peterhof and Kronstadt.

The scheme of the telegraph apparatus

The receiver consisted of coils, each of which was connected to the connecting wires, and magnetic arrows suspended above the coils on the filaments. On the same threads, one cup, colored on one side in black, and on the other in white, was strengthened. When the transmitter key was pressed, the magnetic needle over the coil deflected and moved the circle to the corresponding position. By combinations of arrangements of circles, the telegraph operator at the reception on a special alphabet (code) determined the transmitted sign.

First, eight wires were required for communication, then the number of them was reduced to two. For the operation of such a telegraph apparatus, P. L. Schilling developed a special code. All subsequent inventors in the field of telegraphy used the principles of transmission coding.

Other developments

Almost simultaneously telegraphic apparatus of a similar design, using induction of currents, were developed by German scientists Weber and Gaus. Already in 1833 they conducted a telegraph line at the University of Gottingen (Lower Saxony) between astronomical and magnetic observatories.

It is known for certain that Schilling's apparatus served as the prototype for the telegraph of the English Cook and Winston. Cook met with the works of the Russian inventor at Heidelberg University (Germany). Together with his companion Winston, they perfected the apparatus and patented it. The device enjoyed great commercial success in Europe.

A small revolution in 1838 was made by Steingeil. Not only did he make the first telegraph line for a long distance (5 km), he also accidentally made a discovery that only one wire can be used for signal transmission (the earth is the role of the second one).

Telegraphic device Morse

However, all these devices with dials and magnetic arrows had an irreparable drawback - they could not be stabilized: with rapid information transfer, errors occurred, and the text was distorted. The work on creating a simple and reliable telegraphy scheme with two wires was completed by an American artist and inventor Samuel Morse. He developed and applied a telegraph code in which each letter of the alphabet was designated by certain combinations of points and dashes.

Morse telegraph is very simple. To close and interrupt the current use a key (manipulator). It consists of a lever made of metal, whose axis is connected with a linear wire. One end of the manipulator arm springs against the metal protrusion connected by the wire to the receiver and to the ground (grounding is used). When the telegraph operator pushes the other end of the lever, it touches another protrusion connected by the wire to the battery. At this moment, the current rushes along the line to the receiving device located elsewhere.

At the receiving station, a narrow tape of paper is wound on a special drum, continuously moved by the clockwork mechanism. Under the action of the incoming current, the electromagnet attracts to itself an iron rod, which pierces the paper, thereby forming sequences of signs.

Inventions of Academician Jacobi

The Russian scientist, academician B. S. Jacobi in the period from 1839 to 1850 created several types of telegraph apparatus: writing, arrow synchronous and in-phase action and the world's first direct-printing telegraph apparatus. The latter invention was a new milestone in the development of communication systems. Agree, it is much more convenient to immediately read the telegram sent than to waste time deciphering it.

The transmitting Jacobi's letter-printing apparatus consisted of a dial with an arrow and a contact drum. On the outer circle of the dial were written letters and numbers. The receiver had a dial with an arrow, and besides, the advancing and printing electromagnets and a typical wheel. On the model wheel, all letters and numbers were engraved. When starting up the transmitting device from the current pulses coming from the line, the printing electromagnet of the receiving apparatus worked, pressed the paper tape to the type wheel and printed on the paper the received sign.

Apparatus Hughes

The American inventor David Edward Hughes approved the method of synchronous work in telegraphy, having constructed in 1855 a letter-printing telegraph with a typical wheel of continuous rotation. The transmitter of this device was a piano-type keyboard, with 28 white and black keys, on which letters and numbers were printed.

In 1865 the apparatuses of Hughes were installed to organize telegraph communication between Petersburg and Moscow, and then spread throughout Russia. These devices were widely used until the 30-ies of the XX century.

Bodo apparatus

The Hughes apparatus could not provide high speed of telegraphy and efficient use of the communication line. Therefore, these apparatuses were replaced by multiple telegraphs, designed in 1874 by the French engineer Georges Emile Bodot.

The Bodo apparatus allows simultaneous transmission of several telegrams in both directions to several telegraphists along the same line. The device contains a distributor and several transmitting and receiving devices. The transmitter keyboard consists of five keys. To increase the efficiency of using the communication line in the Bodo apparatus, a transmitter device is used in which the transmitted information is manually coded by the telegraph operator.

Operating principle

The transmitting device (keypad) of the apparatus of one station is automatically connected through the line for short periods of time to the respective receiving devices. The order of their connection and the accuracy of the coincidences of the switching points are provided by the valves. The rate of work of the telegraph operator must coincide with the work of the distributors. The brushes of the transmission and reception valves must rotate synchronously and in phase. Depending on the number of transmitting and receiving devices connected to the distributor, the capacity of the Bodo telegraph apparatus fluctuates between 2,500 and 5,000 words per hour.

The first Bodo apparatuses were installed on the Petersburg-Moscow telegraph connection in 1904. In the future, these devices were widely used in the Soviet telegraph network and were used until the 1950s.

Start-stop apparatus

The start-stop telegraph apparatus marked a new stage in the development of telegraph equipment. The device is small in size, and it is more simple to operate. It used for the first time a typewriter type keyboard. These advantages led to the fact that by the end of the 50s the Bodo apparatus had been completely superseded from telegraph points.

A major contribution to the development of domestic start-stop devices was made by AF Shorin and LI Treml, whose development in 1929 the domestic industry began to produce new telegraph systems. Since 1935, the production of devices of the ST-35 model began, in the 1960s an automatic transmitter (transmitter) and an automatic receiver (reperforator) were developed for them.

Encoding

Since the CT-35 devices were used for telegraph communication in parallel with the Bodo devices, a special code No. 1 was developed for them, which differed from the generally accepted international code for startstops (code No. 2).

After the decommissioning of Bodo vehicles, the need to use a non-standard start-stop code in our country was eliminated, and the entire operating fleet of ST-35 was transferred to international code No. 2. The devices themselves, both modernized and new design, received the name ST-2M and STA-2M (with prefixes of automation).

Rolling machines

Further developments in the USSR were aimed at creating a highly efficient roll telegraph apparatus. Its feature is that the text is printed line by line on a wide sheet of paper, like a dot matrix printer. High performance and the ability to transmit large amounts of information were important not so much for ordinary citizens as for business facilities and government structures.

• The roll telegraph apparatus T-63 is equipped with three registers: Latin, Russian and digital. With the help of punched tape, it can automatically receive and transmit data. Printing occurs on a roll of paper 210 mm wide.
• The automated roll-type electronic telegraph apparatus PTA-80 allows both manual and automatic transfer and acceptance of correspondence.
• RTM-51 and PTA-50-2 devices use 13-millimeter dye tape and standard width paper (215 mm) for recording messages. Per minute, the machine prints up to 430 characters.

The newest time

Telegraphic devices, photos of which can be found on the pages of publications and in museum expositions, played a significant role in accelerating progress. Despite the rapid development of telephone communication, these devices did not go into oblivion, but evolved into modern fax machines and more sophisticated electronic telegraphs.

Officially, the last wired telegraph, functioning in the Indian state of Goa, was closed on July 14, 2014. Despite the huge demand (5000 telegrams daily), the service was unprofitable. In the United States, the last telegraph company Western Union ceased to perform direct functions in 2006, focusing on remittances. Meanwhile, the era of telegraphs did not end, but moved to the electronic environment. The Central Telegraph of Russia, although significantly reduced staff, still fulfills its duties, since not every village in a vast territory has the opportunity to conduct a telephone line and the Internet.

In the newest period, telegraph communication was carried out through frequency-based telegraphy, organized primarily through cable and radio relay lines. The main advantage of frequency wiring was that it allows to organize from 17 to 44 telegraph channels in one standard telephone channel. In addition, frequency wiring makes it possible to communicate practically to any distance. The communication network, composed of channels of frequency telegraphy, is easy to maintain, and also has the flexibility, which allows creating bypass directions in case of failure of linear means of the main direction. Frequency telegraphy proved to be so convenient, economical and reliable that at present telegraph channels of direct current are used less and less.