Letter printing machine and multiple telegraphy. Telegraph devices: types, diagram and photo Primitive types of communication

Printing machine and multiple telegraphy

A huge step forward was the invention of multiple telegraphy, in which one communication line was sufficient for several devices. In this case, a special device - a distributor - connects the devices to the line one by one. Depending on how many telegrams these devices allow to transmit and receive simultaneously, they are called double, quadruple, etc.

In 1863, Russian inventor Vladimir Strubinsky developed the design of a multiple telegraph apparatus, in which two transmitters were connected to the communication line through a special device. This device could have been used on telegraph lines of that time. However, this wonderful Russian invention was buried. A sealed package with a diagram and description of the invention was discovered in the Central Historical Archive in Leningrad only in 1948. Tsarist officials did not even bother to familiarize themselves with Strubinsky’s proposal. When the multiple Bodo telegraph apparatus appeared abroad in 1874, Russia was forced to pay for it in gold.

The Baudot apparatus made it possible to reuse communication lines. But it still did not work quite satisfactorily. Russian scientists and inventors (P. A. Azbukin, A. P. Yakovlev and others) made a number of improvements in this device. Great achievements in the further use of the principle of multiple telegraphy belong to Soviet engineers, Stalin Prize laureates A.D. Ignatiev, L.P. Turin and G.P. Kozlov, who developed an electronic distributor and created a powerful (nine-fold) direct-printing telegraph apparatus.

The principle of multiple telegraphy is very simple. To do this, a so-called distributor is connected to the communication line, which contains a small electric motor that continuously rotates the contact brush. The brush moves along two metal concentric rings. The inner ring is solid and connected to the communication line. The outer ring is divided into several parts (sectors) isolated from each other, to which conductors from telegraph devices are connected.

Performing a circular motion, the contact brush sequentially connects first one or the other sector to the inner ring, each time connecting the corresponding telegraph apparatus to the communication line.

The most common of the multiple telegraph apparatuses is the so-called double Baudot-duplex apparatus. The duplex telegraph system is designed in such a way that it allows you to organize four channels in one telegraph wire: two transmitting and two receiving. In this case, the transmission of telegrams does not interfere with the reception of telegrams, which is simultaneously carried out over the same wire.

Let's consider the process of transmitting a telegram from the first (transmitting) station to the second (receiving) station. The duplex device installed at each station has two keyboards (for transmitting telegrams) and two receivers (for receiving telegrams). Therefore, four telegraph operators work on it at once. For each revolution of the control brush on the distributor of the transmitting station, keyboards No. 1 and No. 2 are alternately connected to the communication line. At the same time, at the receiving station, receivers No. 1 and No. 2 are connected to the communication line by the same distributor and at the same moments. moves along the first sector, it connects keyboard No. 1 to the communication line, and when it moves along the second sector, it connects keyboard No. 2. At these moments, two telegrams are transmitted. At the second station, due to the presence of a duplex circuit, when transmitting telegrams, the same process occurs, but in the opposite direction. Thus, four telegrams are transmitted over one communication line: two in one direction and two in the other direction.

Of course, in reality the structure of the Baudot apparatus is much more complicated than described here. After all, the brushes of the distributors of the devices must move in a strictly coordinated manner. If the brush in the apparatus installed at one station moves along sector No. 1, then in the apparatus of another station at the same time the brush must also move along sector No. 1.

All these clarifications (corrections) of the operation of the two devices are made using special circuits with relays and electromagnets and a system of mechanical parts.

The Baudot apparatus uses a five-key transmitter, similar to the one invented by Schilling. When the keys are not pressed, current pulses of negative polarity (from the “minus” of the electric battery) are constantly sent into the line. When you press a key, the polarity of the pulses sent changes, since the contact of the pressed key is disconnected from the minus of the first battery and connected to the plus of the other battery. From combinations of positive and negative current pulses, telegram characters are composed: letters, numbers and punctuation marks.

Each key has two positions (“pressed”, “not pressed”). Five keys can produce 22 2 2 2 = 32 different, non-repeating combinations. For example: only the first key is pressed, or: the third and fourth keys are pressed, etc. In practice, only 31 combinations can be used, since the “idle” combination disappears when no key is pressed, i.e. when they go in a line only one “minus” current pulses. A telegram can contain 57 different characters (32 letters of the alphabet, 10 numbers, punctuation marks and auxiliary signs). To transmit such a number of characters, you would need not five, but six keys. But it would be difficult for a telegraph operator to work on six keys. Therefore, they came up with another device, thanks to which the same combination of positive and negative current pulses is used twice. Wanting to transmit letters, the telegraph operator dials a special combination - switch to letters, and if you need to transmit a number, then another combination - switch to numbers.

In the receiver, the so-called register device reacts to these clicks, and either letters or numbers are imprinted on the tape.

The work of a telegraph operator of a five-key multiple device requires not only knowledge, but also great skill, flexibility of fingers and even some art. The telegraph operator, pressing the keys, operates with two fingers of his left hand and three fingers of his right. Letters and numbers are imprinted on the tape of the receiving station apparatus using a standard wheel, designed according to the principle of the wheel of a Jacobi apparatus (Fig. 9).

Rice. 9. Standard wheel.

On the edge of a standard wheel there are letters of both the Russian and Latin alphabets, and this is very convenient for exchanging telegrams with our union republics and with other countries.

To monitor the correct transmission of telegrams, a control device is connected to the transmitting keyboard circuit. Then, in front of the telegraph operator transmitting the telegram, the same telegram is printed on a paper tape.

The Baudot apparatus operates over steel overhead line wires over a distance of up to 600 kilometers. To increase the range, intermediate stations (broadcasts) are installed.

Multiple telegraph devices allow you to work at high speed and have great power. So, for example, the M-44 apparatus employs one telegraph operator who transmits (or receives) only 400 words per hour. At a telegraph station, where a multiple device of the most common type “double Baudot duplex” is installed, transmission (as well as reception) is carried out by each telegraph operator at a speed of 900 words per hour. As we have already said, four telegraph operators work on this device simultaneously, two of whom transmit telegrams, and two receive. Thus, in one hour they transmit and receive 3600 words. The Soviet nine-fold telegraph apparatus mentioned above has the greatest power. At each telegraph station, equipped with a nine-fold apparatus, nine telegraph operators work simultaneously on transmission and nine telegraph operators on reception. In one hour, these 18 telegraph operators manage to transmit and receive up to 20 thousand words per hour.

The presence of several channels for transmitting and receiving telegrams is a great advantage of the multiple telegraphy system. But the devices of this system also have disadvantages: bulkiness, complexity of design and adjustment, etc. In addition, specially trained telegraph operators are needed to service such devices. Another Soviet direct-printing telegraph apparatus ST-35 is free from these shortcomings.

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Start-stop apparatus ST-35 The ST-35 apparatus was created by Soviet engineers in 1935. It is the most common, widespread device on our telegraph lines (Fig. 10). Rice. 10. Tape start-stop telegraph device ST-35. The ST-35 device is small in size. His

At the points of origin (consumption), the message is usually presented to the user (user) in non-electrical form in the form of a record on a medium: paper form, punched tape, punched card, magnetic tape, etc. Electrical communication channels are mainly used to transmit this information. Thus, the problem arises of converting a message from a non-electrical form into electrical signals on the transmitting side and, in reverse conversion, on the receiving side. As noted above, message transfer terminals are used for this purpose.

One of the most popular terminal devices is the direct-printing TA. Its main purpose is to transmit, receive or prepare alphanumeric messages. The industry produces TAs that provide both transmission and reception of telegraph messages. In this case, it is allowed to use the TA only for transmitting or only for receiving messages. In the first case, the receiving part of the device serves to control “its” transmission, in the second, the transmitting part is not used.

Rice. 4.8. Block diagram of a telegraph apparatus

The design also provides for separate use of the receiving and transmitting parts of the TA. At the same time, there is no control over “your” work.

A generalized block diagram of the TA is shown in Fig. 4.8. As can be seen, its main parts are a transmitting device, a receiving device and a control device (including an electric drive).

The transmitting device is designed to convert user message characters into code combinations and sequentially transmit single elements of code combinations in the form of an electrical signal over a communication channel.

The receiving device solves the inverse problem - it converts code combinations sequentially arriving from the communication channel into corresponding message characters that are recorded on the medium. The control device serves to coordinate the interaction of individual units of the device, synchronization and drive.

In addition, TAs have various auxiliary devices that expand its functionality and facilitate operation (automation, visualization, alarm devices, etc.).

The TA transmitting device includes the following main components: input device CU, encoding device CU, storage device CU, transmission distributor, service signal sensor DSS, output device.

The VU device is designed to enter information into the telegraph apparatus in the form of message signs. It controls the KU. In some TAs, the transmission distributor is started by a signal from the control unit. In a typewriter, the role of a computer is played by a keyboard (like a typewriter keyboard). Entering messages using the keyboard is done manually. It is also possible to automatically enter information either directly from the message source (for example, a computer) or from an intermediate medium (punched paper tape, magnetic tape, etc.).

The encoding device is designed to convert a message sign into a code combination corresponding to this sign. It can be mechanical or electronic. A signal about the need to form one of N code combinations is received at the input of the CU from the output of the control unit. The number of CU outputs is equal to the number of elements of the code combination. Since uniform binary codes are used in TA, all code combinations contain the same number of unit elements, which can only have two values - 0 and 1. The encoding device must ensure correspondence between the telegraph message character and the code combination. Single elements of the code combination are simultaneously (in parallel) supplied to the memory input.

The transmitter's storage device is designed to store information single elements of the code combination for the duration of its transmission.

The transmission distributor is designed to sequentially read single elements of a code combination from the memory and transfer them one by one to the . In addition to the information elements of the code combination representing the message sign, it also adds so-called service elements necessary for synchronizing the receiving device.

Service elements, for example, the start element, which fixes the beginning of the combination, and the stop element, which fixes the end, are generated by a service signal sensor (DSS) in the start-stop transmission method.

The set of information and service elements determines the transmission cycle of the distributor. The duration of the transmission cycle can be expressed by the formula where k is the number of information elements; - number of service unit elements; - duration of a single element.

The device is designed to generate electrical signals with certain parameters (amplitude, shape) suitable for transmission over the communication channel used.

Rice. 4.9 Formation of a start-stop code combination

In most cases, single-pole single elements (packages) of rectangular direct current are formed (Fig. 4.9).

The receiving device TA consists of the following main components: the input device of the registration device UR, the receiving distributor of the synchronization device US, the storage device ZU, the decoding device remote control and the printing device PU.

The receiver input device is designed to convert signals coming from the line into a form convenient for use in other nodes of the receiving part of the telephone. Passing through a communication channel, telegraph signals are exposed to various types of interference, which leads to a change in their shape. Therefore, it plays the role of a shaper, converting signals distorted in shape into rectangular parcels (single elements).

To record the state of each received element in any discrete message receiver, including the TA, there is a UR registration device. A rational choice of registration method for the communication channel used (gating, integration or a combined method) allows you to obtain a minimum error rate.

The receiving distributor is designed to alternately connect k memory cells to the SD in order to distribute sequentially arriving k information single elements of the code combination among k memory cells.

To ensure correct registration and correct distribution of received information elements among memory cells in the TA, a synchronization device is used. It performs clock and cycle synchronization.

As noted above, the transmitter DSS produces service (start and stop) elements that mark the moments of the beginning and end of the transmission cycle. These service elements are perceived by the receiver's CS, which, acting on the UR, ensures the correct choice of moments for registering the elements of the code combination and their correct distribution among the memory cells of the TA receiver.

The receiver's storage device is designed to sequentially accumulate single elements of the received code combination. After registering the last element, the memory outputs the received code combination to the remote control decoding device, which is designed to decrypt the received code combinations. It converts the code combination into a message sign, i.e., it performs the opposite task to the transmitter’s encoding device KU. Sometimes the remote control is called a decoder or decoder. It is obvious that the decoder, when entering a code combination from the memory in parallel, has k inputs and outputs.

The printing device PU of the receiving part of the TA is designed to print message characters on the medium (paper tape, roll, etc.) upon the corresponding signal from the remote control.

Before the widespread introduction of digital technology elements in communication equipment, TAs were built mainly on mechanical elements. However, such TTs have a number of disadvantages, among which the main ones are: relatively low transmission speed (no more than baud), low reliability, large mass, noise, etc. The implementation of TTs based on digital integrated and microprocessor technology has significantly improved their technical and economic indicators . At the same time, new opportunities have emerged to expand the functionality of the TA. On the other hand, the electronicization of the TA and the use of software methods for changing the functionality of the device have created the need for new design solutions. A modern electronic telegraph apparatus (ETA) is characterized by some implementation features. As noted above, ETA can work as an end device of a computing system, that is, act as a terminal. Therefore, it provides for the presence of transmitting and receiving memory, an information display device and the ability to simultaneously operate in linear and local modes. Information is transferred to ETA using a keyboard, transmitter or from an electronic memory. The ETA block diagram is shown in Fig. 4.10.

Rice. 4.10 ETA block diagram

Rice. 4.11 Operating principles of the key

The transmitting drive is designed to accumulate messages in the event that the operator exceeds the telegraph speed, which allows the keyboard to be executed without mechanical locking. ETA reperforators mainly use a mechanical method for punching holes on the tape. The receiving drive in the control unit is necessary to accumulate information received during the period of time spent returning the carriage of the roll machine. The electronic decoder functionally consists of two parts - a code decoder and a service combination decoder.

The printing unit contains a mechanism for advancing paper, a carriage to the beginning of the line, and an ink ribbon. All mechanisms in ETA are driven by stepper motors.

Telegraph devices, lines, current sources constitute the main elements of telegraph communication

All telegraph messages are transmitted at a certain speed. Telegraph speed is measured by the number of elementary telegraph parcels transmitted in 1 second. The telegraph speed unit is the baud (introduced in 1927).

If, for example, 50 elementary telegraph parcels per second are transmitted on any communication line, then the telegraph speed is 50 baud. In this case, the duration of one chip is 1/50 = 0.02 s = 20 ms.

The receiver of a telegraph apparatus is an electromagnet, through the windings of which current flows from the line. With the help of an electromagnet, the energy of electric current is converted into mechanical energy of movement of the recording device of the telegraph apparatus.

An electromagnet consists of a winding, a core and an armature. The current from the line flows through the winding, resulting in a magnetic field that acts on the armature, which is attracted to the core, turning around its axis.

When the telegraph current transmission stops, the field in the core disappears, and the armature returns to its original position under the action of the spring.

A linear relay is used for more reliable operation of a telegraph apparatus at lower currents; it is connected between the communication line and the electromagnet of the telegraph apparatus.

Telegraphy methods are distinguished by the nature of current transmissions when transmitting code combinations from one station to another and by the method of coordinating the operating rhythms of receiving and transmitting devices.

Code combinations can be transmitted by direct or alternating current parcels.

When telegraphing with direct current, a distinction is made between single-pole and double-pole telegraphy. When current transmissions of one direction (positive or negative) are transmitted to the line, telegraphing is called single-pole and the pause between the transmissions corresponds to the absence of current in the line. This method is also called passive pause telegraphing.

When a working signal is transmitted by a current in one direction (for example, plus), and a pause is transmitted by a current in another direction (for example, minus), such telegraphing is called bipolar or telegraphing with an active pause.

With single-pole telegraphy, one linear battery is used at one station. With two-pole telegraphy, two line batteries are needed, each of which is connected to the line through the transmitter with different poles. If the transmitter and receiver operate synchronously and in phase, then this telegraphy method is called synchronous.

Currently, the start-stop telegraphy method is used. The origin of this name is explained by the fact that the distributor begins to operate only at the “start” signal and after each cycle stops at the “stop” signal. To start and stop the distributor with the start-stop method, in addition to information parcels, it is necessary to transmit two more service parcels along the line - start and stop.

The synchronous method in combination with the start-stop method is called synchronous-start-stop. This method allows telegraphy to be carried out over one line from several start-stop devices using a synchronous distributor.

When telegraphing with direct current, the range is limited to the distance at which on the receiving side of the line the amplitude of the direct current sending is sufficient to trigger the receiving electromagnet or relay. To increase the telegraphing range, it is necessary to increase the DC voltage or enable pulse broadcasting. However, DC voltage amplification involves significant technical difficulties, and the use of translations is limited by the accompanying pulse distortion. Transmission of several messages by direct current parcels requires a separate communication line for each message.

Increasing the telegraphing range and increasing the efficiency of use (compression) of the communication line are easily solved using frequency telegraphy (alternating current telegraphy). The telegraphing range is not limited, since it is easy to organize amplification of alternating current signals. Thanks to the compression of communication lines, several dozen telegraph messages can be transmitted simultaneously.

Telegraph range they call the greatest distance between two stations at which reliable transmission of messages can be carried out without the use of any intermediate amplifying devices.

In facsimile telegraph communication, a still image is transmitted via electrical communication channels. The source of the message to be transmitted may be text, graphic or photographic material. A feature of fax communication is the brightness of the elementary areas and their density on the surface of the transmitted image, called the original. On the receiving side, the distribution of the original elements must be reproduced with a given accuracy. The image received at the receiving end is called a copy.

Subscriber telegraph is used to organize temporary direct telegraph connections between different subscribers. The station equipment includes switching devices and relay panels containing telegraph and telephone relays, which provide conversion and transmission of signals and the necessary control of switching processes. According to the switching method, stations are divided into two types: manual stations - (ATR) and automatic (ATA).

An ATP station is a complex of switching equipment in which all connections are made by a telegraph operator using manual cord pairs. Such stations remained in the network in small numbers and in the future will be completely replaced by automatic stations.

Subscribers included in the ATA station themselves control the process of establishing a connection using a dialer. Automatic connections are possible both with a subscriber included in the ATA station, and with a subscriber included in the ATP station, by calling the telegraph operator of this station.

According to the type of switching equipment used, ATAs are divided into decade-step and coordinate.

By capacity, ten-step stations can be divided into three main types:

Type I - ATA-57 with a capacity of up to 1000 subscriber installations;

Type II - ATA-57 with a capacity of up to 300 subscriber installations;

Type III - ATA-M with a capacity of up to 20 subscriber installations.

Based on capacity, coordinate stations are divided into two types:

Type I - high-capacity ATA-K stations, to which up to 500 subscriber installations can be connected;

Type II - low-capacity ATA-MK stations, to which up to 20 subscriber installations can be connected.

High-capacity ten-step and coordinate stations are designed for installation in large telegraph nodes with a large number of subscriber installations and significant transit traffic, and small-capacity stations such as ATA-M and ATA-MK are installed in small telegraph nodes.

The equipment of ATA stations is built in such a way that it allows the channels for the subscriber telegraph (AT) network and direct connections (DS) to be used together on the backbone section. At the same time, due to operational differences, the switching equipment of automatic stations (ATA) and automatic stations of direct connections (APS) is built in such a way that direct connection of subscribers of these stations with each other is technically impossible.

Direct connection switching stations (DSS) are intended for organizing temporary direct telegraph connections between the end points of the telegraph network.

In addition to those listed, the country's telegraph network includes a network of non-switched (leased) channels.

In accordance with the diverse requirements of users, three switching methods are currently used in telegraph networks: switching channels (kk), messages (ks) and packets (kp).

At circuit switching Between the calling and called subscribers, with the help of circuit switching nodes, an end-to-end channel is organized through which information is transmitted.

In this switching method, the connection establishment procedure begins with making a call. If the station is ready to receive a number, it transmits a dialing invitation signal to the caller. The subscriber transmits the number of the called subscriber to the station.

The switching station, having received the number of the called subscriber, determines the direction of the adjacent station and transmits the received number to it. The incoming station finds the line of the called subscriber and, if it is free, lays out the connection path between the subscribers. The connection establishment signal is broadcast to the calling subscriber. Along the formed path, messages are transmitted both in one and the other direction. After the end of the two-way exchange of messages, one of the subscribers sends a hang-up signal and the established connection is disconnected.

Message switching is a method of information distribution in which individual messages are transmitted over the network, equipped with headers that include the recipient's address and service information. At each node, the message is written to a storage device, the address is analyzed and the further direction of transmission is selected. If there is a free channel in a given transmission direction, then the message is transmitted immediately, otherwise the message is placed in a queue in which it will remain until the channel is freed.

The subscriber sends a message to the switching center (SSC) requesting the transmission of a message. If the MSC is ready to receive a message, it sends an invitation signal to the caller to send the message. The subscriber sends a message to the center. Having fully accepted the message from the subscriber, the MSC sends him a confirmation signal. At the end sections, messages are transmitted at low speed. On discrete channels between digital data centers, the transmission speed is usually higher, as shown by the change in the duration of message transmission. In each center, the received message is recorded on a storage device, on magnetic tapes or magnetic disks. The message header is analyzed and the direction of subsequent transmission is determined. All incoming messages are distributed into queues for outgoing directions. When the channel is released, the message is transmitted to the adjacent switching center, where the process is completely repeated.

Packet switching is a method of distributing information in which messages are divided into separate blocks, each of which is equipped with a special header. At the switching center, the blocks are processed and written to random access memory (RAM). The header is analyzed and the direction of subsequent packet transmission is determined. If the channel in this direction is free, the packet is transmitted; if it is busy, the packet is queued for transmission.

There are two methods of packet switching: datagram and method of transmitting packets over a virtual channel. In the datagram method, each packet is transmitted independently of the other packets of the same message, with different packets of the same message sent along different routes. Therefore, packets arrive at the receiving switching node in a random order with different delay times. At the receiving node, the true order of the packets in the message is restored, the packet headers are erased, and the restored message is transmitted to the recipient.

When transmitting packets over virtual channels, the “Call Request” service packet is first transmitted, which lays out a single route in the network along which all other packets of this message will be transmitted. This route is assigned the number of the installed logical channel. During the transmission process, each packet is assigned a logical channel number, according to which everyone participating in the organization of the virtual channel determines the direction of further transmission of the packets. All packets of one message are transmitted sequentially one after another with exactly the same delays. At the destination node, all packets are collected and the recovered message is transmitted to the recipient. After delivery of the entire message, one of the subscribers transmits a “disconnection request” service packet, which, passing through the switching nodes, destroys the virtual channel number recorded in them, leading to its destruction.

At school for the summer they always assigned an overwhelming list of literature - usually I only had enough for half of it, and I read it all in a short summary. “War and Peace” on five pages - what could be better... I’ll tell you about the history of telegraphs in a similar genre, but the general meaning should be clear.

The word "telegraph" comes from two ancient Greek words - tele (far) and grapho (writing). In its modern meaning, it is simply a means of transmitting signals via wires, radio or other communication channels... Although the first telegraphs were wireless - long before they learned to correspond and transmit any information over long distances, people learned to knock, wink, make fires and beating drums - all this can also be considered telegraphs.

Believe it or not, once upon a time in Holland they generally transmitted messages (primitive) using windmills, of which there were a huge number - they simply stopped the wings in certain positions. Perhaps this is what once (in 1792) inspired Claude Chaf to create the first (among non-primitive) telegraph. The invention was called “Heliograph” (optical telegraph) - as you can easily guess from the name, this device made it possible to transmit information using sunlight, or more precisely, due to its reflection in a system of mirrors.

Between cities, in direct visibility from each other, special towers were erected, on which huge articulated semaphore wings were installed - the telegraph operator received the message and immediately transmitted it further, moving the wings with levers. In addition to the installation itself, Claude also came up with his own symbol language, which thus made it possible to transmit messages at a speed of up to 2 words per minute. By the way, the longest line (1200 km) was built in the 19th century between St. Petersburg and Warsaw - the signal traveled from end to end in 15 minutes.
Electric telegraphs became possible only when people began to study the nature of electricity more closely, that is, around the 18th century. The first article about the electric telegraph appeared on the pages of a scientific journal in 1753 under the authorship of a certain “C. M." — the author of the project proposed sending electric charges along numerous insulated wires connecting points A and B. The number of wires had to correspond to the number of letters in the alphabet: “ The balls at the ends of the wires will become electrified and attract light bodies with the image of letters" Later it became known that under “C. M." Scottish scientist Charles Morrison was hiding, who, unfortunately, was never able to establish the correct operation of his device. But he acted nobly: he treated other scientists to his work and gave them an idea, and they soon proposed various improvements to the scheme.

Among the first was the Genevan physicist Georg Lesage, who in 1774 built the first working electrostatic telegraph (he also proposed laying telegraph wires underground in clay pipes in 1782). All the same 24 (or 25) wires isolated from each other, each corresponding to its own letter of the alphabet; the ends of the wires are connected to an “electric pendulum” - by transferring a charge of electricity (back then they were still rubbing ebonite sticks with might and main), you can force the corresponding electric pendulum of another station to come out of equilibrium. Not the fastest option (transmitting a small phrase could take 2-3 hours), but at least it worked. Thirteen years later, Lesage's telegraph was improved by the physicist Lomon, who reduced the number of required wiring to one.

Electric telegraphy began to develop intensively, but it gave truly brilliant results only when it began to use not static electricity, but galvanic current - food for thought in this direction was first suggested (in 1800) by Alessandro Giuseppe Antonio Anastasio Gerolamo Umberto Volta. The first to notice the deflecting effect of galvanic current on a magnetic needle was the Italian scientist Romagnesi in 1802, and already in 1809 the Munich academician Soemmering invented the first telegraph based on the chemical effects of current.

Later, a Russian scientist, namely Pavel Lvovich Schilling, decided to participate in the process of creating the telegraph - in 1832 he became the creator of the first electromagnetic telegraph (and later - also the original code for operation). The design of the fruit of his efforts was as follows: five magnetic needles suspended on silk threads moved inside “multipliers” (coils with a large number of turns of wire). Depending on the direction of the current, the magnetic arrow went in one direction or another, and a small cardboard disk turned along with the arrow. Using two directions of current and an original code (composed of combinations of disc deflections of six multipliers), it was possible to transmit all the letters of the alphabet and even numbers.

Schilling was asked to build a telegraph line between Kronstadt and St. Petersburg, but in 1837 he died and the project was frozen. Only almost 20 years later it was resumed by another scientist, Boris Semyonovich Jacobi - among other things, he thought about how to record the received signals and began working on a project for a writing telegraph. The task was completed - the symbols were written down by a pencil attached to the armature of the electromagnet.

Also, Carl Gauss and Wilhelm Weber (Germany, 1833) and Cook and Wheatstone (Great Britain, 1837) invented their own electromagnetic telegraphs (or even the “language” for them). Oh, I almost forgot about Samuel Morse, although I already mentioned him. In general, we have finally learned how to transmit an electromagnetic signal over long distances. So it started - at first simple messages, then correspondent networks began to transmit news by telegraph for many newspapers, then entire telegraph agencies appeared.

The problem was the transfer of information between continents - how to stretch more than 3000 km (from Europe to America) of wire across the Atlantic Ocean? Surprisingly, that’s exactly what they decided to do. The initiator was Cyrus West Field, one of the founders of the Atlantic Telegraph Company, who organized a hard party for local oligarchs and convinced them to sponsor the project. The result was a “tangle” of cable weighing 3,000 tons (consisting of 530 thousand kilometers of copper wire), which by August 5, 1858 was successfully unwound along the bottom of the Atlantic Ocean by the largest warships of Great Britain and the United States at that time - Agamemnon and Niagara. . Later, however, the cable broke - not the first time, but it was repaired.

The inconvenience of the Morse telegraph was that its code could only be deciphered by specialists, while it was completely incomprehensible to ordinary people. Therefore, in subsequent years, many inventors worked to create a device that recorded the text of the message itself, and not just the telegraph code. The most famous among them was the Yuze direct printing machine:

Thomas Edison decided to partially mechanize (facilitate) the work of telegraph operators - he proposed completely eliminating human participation by recording telegrams on punched tape.

The tape was made on a reperforator - a device for punching holes in a paper tape in accordance with the telegraph code signs coming from the telegraph transmitter.

The reperforator received telegrams at transit telegraph stations, and then transmitted them automatically - using a transmitter, thereby eliminating the labor-intensive manual processing of transit telegrams (sticking a tape with characters printed on it onto a form and then transmitting all the symbols manually from the keyboard). There were also repertotransmitters - devices for receiving and transmitting telegrams, performing the functions of a reperforator and transmitter simultaneously.

In 1843, faxes appeared (few people know that they appeared before the telephone) - they were invented by a Scottish watchmaker, Alexander Bain. His device (which he himself called the Bane telegraph) was capable of transmitting copies of not only text, but also images (albeit in disgusting quality) over long distances. In 1855, his invention was improved by Giovanni Caselli, improving the quality of image transmission.

True, the process was quite labor-intensive, judge for yourself: the original image had to be transferred to a special lead foil, which was “scanned” by a special pen attached to a pendulum. Dark and light areas of the image were transmitted in the form of electrical impulses and reproduced on the receiving device by another pendulum, which “drew” on special moistened paper soaked in a solution of potassium iron sulfide. The device was called a pantelegraph and subsequently enjoyed great popularity around the world (including in Russia).

In 1872, the French inventor Jean Maurice Emile Baudot designed his multiple-action telegraph apparatus - he had the ability to transmit two or more messages in one direction over one wire. The Baudot apparatus and those created on its principle are called start-stop apparatus.

But in addition to the device itself, the inventor also came up with a very successful telegraph code (Bodot Code), which subsequently gained great popularity and received the name International Telegraph Code No. 1 (ITA1). Further modifications to the design of the start-stop telegraph apparatus led to the creation of teleprinters (teletypes), and the unit of information transmission speed, the baud, was named in honor of the scientist.

In 1930, a start-stop telegraph with a telephone-type rotary dialer (teletype) appeared. Such a device, among other things, made it possible to personalize telegraph network subscribers and quickly connect them. Later, such devices began to be called “telex” (from the words “telegraph” and “exchange”).

Nowadays, telegraphs have been abandoned in many countries as an obsolete method of communication, although in Russia it is still used. On the other hand, the same traffic light can also, to some extent, be considered a telegraph, and it is already used at almost every intersection. So, wait a minute to write off old people;)

During the period from 1753 to 1839 in the history of the telegraph, there are about 50 different systems - some of them remained on paper, but there were also those that became the foundation of modern telegraphy. Time passed, technologies and the appearance of devices changed, but the principle of operation remained the same.

What now? Inexpensive SMS messages are slowly disappearing - they are being replaced by all sorts of free solutions like iMessage/WhatsApp/Viber/Telegram and all sorts of asec-Skype. You can write a message " 22:22 - make a wish"and be sure that a person (perhaps located on the other side of the globe) will most likely even have time to wish for it in time. However, you are no longer little and you understand everything yourself... better try to predict what will happen with the transfer of information in the future, after a period of time similar in length?

Photo reports from all museums (with all telegraphs) will be published a little later on the pages of our “historical”

In 1872, the Frenchman J.E. Baudot created a device that made it possible to transmit several telegrams simultaneously over one line, and the data was received no longer in the form of dots and dashes (before that, all such systems were based on Morse code), but in the form of Latin and Russian letters (after careful refinement by domestic specialists ) language. The Baudot apparatus and those created on its principle are called start-stop apparatus. In 1874, he, using a five-digit code as a basis, designed a double-digit device, the transmission speed of which reached 360 characters per minute. In 1876, he created a five-fold device that increased the transmission speed by 2.5 times. The first Baudot devices were put into operation in 1877 on the Paris - Bordeaux line. The Baudot apparatus made it possible to use the pause time between dots and dashes for signal transmission. It became possible, using a special switch, for four, six or more telegraph operators to work on one line at once. The most widespread were double Baudot devices, which worked for long-distance communications almost until the end of the 20th century and transmitted up to 760 characters per minute. In addition to these devices, Baudot developed decoders, printing mechanisms and distributors, which became classic examples of telegraph instruments. In 1927, a unit of telegraph speed was named after Baudot - baud. Baudot's equipment became widespread in many countries and was the highest achievement of telegraph technology in the second half of the 19th century. Further modifications to the design of the start-stop telegraph apparatus proposed by Baudot led to the creation of teleprinters (teletypes). In addition, Baudot created a very successful telegraph code (Baudot Code), which was subsequently adopted everywhere and received the name International Telegraph Code No. 1 (ITA1). The modified version of the code is called ITA2. In the USSR, based on ITA2, the telegraph code MTK-2 was developed.

The telegraph signal amplification point for the Baudot apparatus was placed at a distance of 600-800 km from the transmitting center in order to “drive” the signal further: to work, it was necessary to synchronize the electricity in two channels and carefully monitor the information transmission parameters.

The Baudot device operates in duplex mode (in total, up to six working stations could be connected to one transmitter) - the response data was printed on paper tape, which had to be cut and pasted onto the form.

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