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Émile Baudot 
Magneux (HAUTE MARNE) 11 September  1845 -Sceaux 28 March 1903

 


  
Biographical notes by : IW2GJQ
   


 


Technical French, son of a farmer, Baudot attended only primary and spent adolescence and youth working in father's farm. After his entrance as a substitute, in the lines Telegraphic (16 July 1870), fascinated by the scientific aspects of his new profession, Baudot devoted himself to perfecting his education, in the short time leave he free from work at the central Post Paris.

In 1870 he invented his telegraphic code, the first truly digital, based on two states, both logical ( "1" and "0", units that now call "bit") and physical (power = "1", no current Electrical = "0"). Each character Baudot consists of 5-bit and therefore are available 32 different combinations, which are not enough alone to represent the 26 letters of the Latin, the 10 digits and punctuation. Using two special characters, and LTRS FIGS you will get 64 opportunities. LTRS (11111) above alphabetic characters, FIGS (11011) those numbers and those special, as punctuation.  The natural evolution of the Baudot code were the ASCII codes to 7 and 8 bits that form the basis of the language of today's computers. Before the mid-20 th century, the Baudot code supplanted the Morse as the most used telegraphic alphabet. In fact, its combination of 5 units of equal duration represents a substantial savings to the system Morse of dots and lines. The Baudot code was known as the International Code Telegraphic N. 1

On 17 June 1874 Baudot patented his first apparatus (patent No 103898, "Quick telegraphy system"), which today would call "system division multiplex time. His invention took cue from the printing system a tool Hughes and a distributor invented by Bernard Meyer in 1871 (the 5-bit code was originally conceived by Gauss and Weber). Baudot combined these elements, along with its original ideas, to produce the final multiplex system. Baudot The system was composed of three main elements: the keyboard, the distributor and printer paper tape.
The keyboard resembling that of a piano and had 5 keys, divided into a group of two buttons, left, and a three, right.
The distributor was the heart of the system and connected to it were both receivers and keyboards.  Each keyboard was connected to a set of Rotors that opened and closed contacts on the conductive elements fixed called segments. The brushes rotated thanks to an electric motor or a mechanism weights. Typically, a distributor had from four to six keyboards connected, each with its own set of brushes and buckets.
The receiver was equipped with 5  electro calamity that remembered the received signal and which was automatically decoded the combination to print the resulting directly on a strip of paper.
Since distributor were connected to four or more keyboards, and the distributor of departure and arrival were connected by a single line, this system was the first multiplex success in telecommunications electricity.


The system worked like this:
Operator digit code on the keyboard connected to the distributor, who blocked the keys until the Rotors not passed over segments connected to the keyboard. The keyboard then unblocked, issuing an audible warning signal for the operator, and was ready to receive the next character. This sound was known as signal cadence. The two distributors of departure and arrival were synchronized with each other. The receiver, on the other end, the message directly printed on a strip of paper.
Working with the keyboard Baudot required a lot of skill, because the typing had to be absolutely regular and rhythmic. The normal operating speed was 180 letters per minute.  Baudot The system was accepted by the French in 1875 and the first test in line occurred on November 12, 1877, between Paris and Bordeaux. By the end of that year started a double Baudot telegraphic service on the line Paris-Rome, about 1700 km long. On 27 April 1894 established Baudot, always on a single line, communication between the stock exchange in Paris and Milan and, simultaneously, between the center of Milan and in Paris.
After France, the system telegraphic Baudot entered service in other nations: the first for Italy (1887, for the service inside), then the Netherlands (1895), Switzerland (1896), Austria and Brazil (1897), the United Kingdom (1898, there was the first since a simple tour of the British Post Office between London and Paris), Germany (1900), Russia (1904), India (1905), Spain (1906 ), Belgium (1909), Argentina (1912) and Romania (1913).

 
Clavier Baudot
 

 
Distributer Baudot
 

 
 Print Baudot


The equipment were installed Baudot to Exposition universal Paris in 1878 and won him the great gold medal, in addition to unanimous congratulations engineers from all over the world. Sell this medal in 1880 to further research in the field of telegraphy, as always received a little help Telegraphic by the French and very often had to put their pocket money to finance his experiments.
Baudot died at the age of fifty-seven, after a long illness.

 The inventor was awarded the Legion of Honor in 1879 and promoted controller in 1880 and in 1882 was appointed Engineer finally inspection.


The speed unit in the telegraph transmissions is called Baud in his honor. The Baud was the main unit of measurement data transmissions before being replaced by more accurate bps.

By:IW2GJQ