telegraph played a major role in the development of modern society.Slow and unreliable transmission of information impeded progress, and people were looking for ways to speed up.With the invention of electricity made possible the creation of devices, instantly transmitting important data over long distances.
At the dawn of history
Telegraph in different incarnations - the oldest forms of communication.Even in ancient times there was a need to transfer information from a distance.For example, in Africa, for the transmission of various messages we used drums tom-toms in Europe - the fire, and later - semaphore communication.The first semaphore telegraph was first called "tahigraf" - "skoropisets" but then replaced it with a more appropriate designation called "telegraph" - "dalnopisets."
first device
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 - creator of the first electrochemical cell and the first battery (it was then called "voltaic pile") - there was a lot of ideas of creating electromagnetic telegraph.
Attempts to manufacture electrical devices transmitting signals at some predetermined distance, taken from the late 18th century.In 1774, a simple telegraph was built in Switzerland (Geneva), scientist and inventor Lesage.He joined the two transceivers 24-packs isolated wires.When a pulse is applied by the electrical machine on one of the wires of the first device on the second ball deviated Buzinova corresponding electroscope.Then the technology has improved researcher Lomon (1787), which replaced the 24 per wire.However, this system is difficult to call the telegraph.
telegraph continued to improve.For example, the French physicist Andre Marie Ampere created a transmission device, which consists of 25 magnetic needles suspended from the axes, and 50 and wires.However, the bulky devices made such a machine is almost unusable.
apparatus Schilling
The Russian (Soviet) textbook states that the first telegraph, differs from its predecessors efficiency, simplicity and reliability, has been designed in Russia Paul Lvovich Schilling in 1832.Of course, some countries have disputed this assertion, "promoting" its no less talented scientists.
Proceedings Shilling (many of them, unfortunately, has not been published) in telegraphy contain many interesting projects of electric telegraph.Baron Schilling device was equipped with keys that will switch the electric current in the wires connecting the transmitting and receiving devices.
world's first telegram, which consists of 10 words, was passed October 21, 1832 with a telegraph set in the apartment of Paul L. Schilling.The inventor has also developed a project to connect the cable laying telegraph along the bottom of the Gulf of Finland between Peterhof and Kronstadt.
scheme telegraph
receiving apparatus consisted of coils, each of which includes a connecting wires and magnetic needles suspended on strings above the coils.On these filaments strengthened by one mug, painted on one side black, the other white.When you press a transmitter coil of a magnetic needle is deflected and moves according to the position of the circle.By a combination of locations circles telegraph operator at the reception at a special alphabet (code) determines the transmitted symbol.
first to link required eight wires, then their number has been reduced to two.To use this telegraph PL Schilling developed a special code.All subsequent inventors in the field of telegraphy used the principles of the transfer encoding.
Other developments
Almost simultaneously telegraphs similar design, use induction currents, developed by German scientists Weber and Ghaus.Already in 1833 they had a telegraph line at the University of Göttingen (Lower Saxony) between astronamicheskoy and magnetic observatories.
It is known that the unit Schilling served as the prototype for the British Telegraph Cook and Winston.Cook met with the works of Russian inventor of the University of Heidelberg (Germany).Together with colleague Winston they have perfected and patented the device.Device enjoyed great commercial success in Europe.
small revolution in 1838 made Shteyngeyl.Not only that, he spent the first telegraph line long distance (5 km), so even accidentally made the discovery that signal transmission can be used only one wire (the second part performs a ground).
telegraph Morse
However, all of these devices with dial pointer and magnetic needle had an incurable flaw - they can not be stabilized: the rapid transfer of information fails, and the text did distorted.Finish work on creating a simple and reliable circuit telegraphy with two wires managed by American artist and inventor Samuel Morse.He has developed and applied a telegraph code in which each letter of the alphabet indicate certain combinations of dots and dashes.
It is arranged telegraph Morse code is very simple.For insulation and current interruption using a key (arm).It consists of a lever made of metal, the axis of which communicates with the line conductor.One end of the lever arm, a spring is pressed against the metal tab, wired to the receiver and to the ground (using ground).When the telegraph operator presses the other end of the lever, the projection for the other connected to the battery wire.At this point, current rushes through to a receiving device located in a different place.
at the receiving station on a special drum wound narrow strip of paper moves continuously clockwork.Under the influence of the current entered the electromagnet attracts the iron rod that pierces the paper, thereby forming a sequence of characters.
Inventions academician Jacobi
Russian scientist, academician BS Jacobi in the period from 1839 to 1850 created several types of telegraph: writing, arrow-phase synchronous action and the world's first teleprinter.The latest invention was a new milestone in the development of communication systems.Agree, it is much easier to read once sent a telegram than to spend time on her transcript.
transmitting direct-printing apparatus Jacobi consisted of a dial with an arrow and the drum track.On the outer circle of the dial deposited letters and numbers.The receiver unit has a dial with an arrow, and in addition, to promote and printing electromagnets and wheel types.On a typical wheel engraved with all the letters and numbers.When floating the transmission device from the current pulses coming from the line, the printing electromagnet receiving machine breakdowns, pressed paper tape to the wheel types and is printed on a paper accepted sign.
device Hughes
American inventor, David Edward Hughes approved in telegraphy way to synchronous operation, constructed in 1855 teleprinter with standard wheel continuous rotation.The transmitter of this device was the keyboard-type piano, with 28 black and white keys, which were deposited letters and numbers.
In 1865, Hughes machines have been installed for the organization of telegraph communication between St. Petersburg and Moscow, and then spread throughout Russia.These devices are widely used until the 30-ies of XX century.
device Bodo
device Hughes could not provide high speed wiring and effective use of the link.Therefore, to replace these devices have come multiple telegraphs, constructed in 1874 by the French engineer Georges Emile Baudot.
Bodo device can simultaneously transmit multiple telegraph operator on the same line several telegrams in both directions.The apparatus comprises a distributor, and several transmitting and receiving devices.Keypad transmitter consists of five keys.To improve efficiency in the device link such a device is used Bodo transmitter in which the transmitted information is encoded telegrapher manually.
Operating principle
transmitting device (keyboard) one station unit automatically after the line is connected to the short period of time to the corresponding receivers.The sequence of the connection and the accuracy of matches, points of entry are provided by the distributor.The pace of work telegrapher must match the work of distributors.Brushes distributor transmission and reception must rotate synchronously and in phase.Depending on the number of transmitting and receiving devices connected to the distributor, the performance of the telegraph Bodo varies between 2500-5000 words per hour.
first machines were installed at Bodo telegraph "Petersburg - Moscow" in 1904.In the future, these devices are widely used in the telegraph network of the Soviet Union and used until the 50s.
Jogging machine
Jogging telegraph marked a new stage in the development of telegraph technology.The device is small and it is easier to operate.For the first time I used a typewriter style keyboard.These advantages have led to the end of the 50s Bodo machines were completely pushed out of the wire points.
great contribution to the development of local start-stop devices have AF Shorin and LI Treml, which is developed under the domestic industry in 1929 began to produce the new telegraph system.Since 1935 began production device model CT-35 in 1960 were developed for the automatic transmitter (transmitter) and a receiver circuit (reperforator).
Encoding
Since the CT-35 devices were used for telegraph communication devices along with Bodo, then they have developed a special code №1, which differed from the customary international code of start-stop apparatus (code №2).
After decommissioning Bodo devices no longer need to use in our country is a non-standard start-stop code, and the entire existing fleet of CT-35 was transferred to the International Code №2.Sami devices as upgraded, and new construction, received the name ST-STA-2M and 2M (with prefixes automation).
rolling machines
Further developments in the Soviet Union were pitted against the fact, to create a high roll telegraph.Its peculiarity is that the text is printed on the line by a wide sheet of paper, such as dot-matrix printer.The high performance and the ability to transfer large amounts of information are important not so much for ordinary people, as objects of management and government.
- Round telegraph T-63 has three registers: the Latin, Russian and digital.With the help of punched tape can automatically receive and transmit data.Printing occurs on the paper roll 210 mm wide.
- Automated roll electronic telegraph PTA-80 allows you to set how to manually or automatically send and receive mail.
- devices RTM-51-PTA and 50-2 to log messages using a 13-millimeter ink ribbon and paper roll standard width (215 mm).At the moment the machine prints up to 430 characters.
Contemporary
telegraph, photos of which can be found in the pages of books and museum exhibitions, played a significant role in accelerating progress.Despite the rapid development of telecommunication, these devices are not gone into oblivion, and evolved into the modern fax machines and more advanced electronic telegraph.
Officially, the last wire telegraph to operate in the Indian state of Goa, was closed 14 July 2014.Despite the enormous demand (5,000 telegrams daily), the service was unprofitable.In the US, the latest Western Union Telegraph Company ceased to operate direct function in 2006, focusing on remittances.Meanwhile, the era of Telegraphs has not ended, and moved to the electronic environment.Central Telegraph Russia, though significantly reduced staff, continues to fulfill its obligations, as it is not in every village in the vast area it is possible to hold a telephone line and internet.
In the latest period telegraph channels carried on the frequency telegraphy, organized mainly by cable and microwave radio links.The main advantage of frequency telegraphy was the fact that it allows a standard telephone channel to organize from 17 to 44 and telegraph channels.In addition, the frequency wiring makes it possible to carry out the connection to almost any distance.The communications network consisting of the frequency channel wiring, easy to operate and has the flexibility that allows you to create workarounds direction in case of failure of linear means mainstream.Frequency wiring was so convenient, economical and reliable, which is currently telegraph channels DC are used less and less.
