Emile Baudot                                                                        By Johnny Jung

 

Emile Baudot was born in 1845, Magneux, France and died on March1903, Sceaux. 

Mr. Baudot was of a modest origin. He was the son of a farmer, he had begun his life following the career of his parents; but in 1869, he entered the Administration of Posts and Telegraphs, of which he would become the glory.

Emile Baudot developed a printing telegraph machine which used a typewriter style keyboard, this allowed virtually anyone to send and receive telegraph messages. Baudot used a different type of code for his system because Morse code didn't lend itself to automation, this was due to the uneven length and size of bits required for each letter.

 

Baudot used a five bit code to represent each character, this would normally only give 32 possible combinations (00000 to 11111 = 32). It clearly wasn't enough for 26 letters and 10 digits but he got around this problem by using two 'shift characters' for figures and letters, which performed the same sort of function as a typewriter shift key. Now he had 62 combinations for letters, figures and punctuation marks. To this day, the speed of serial communications is still measured in Baud rate, after Emile Baudot., in 1874 he received a patent on a telegraph code that by the mid-20th century had supplanted Morse Code as the most commonly used telegraphic alphabet.


 

Modern versions of the Baudot Code usually use groups of seven or eight "on" and "off" signals. Groups of seven permit transmission of 128 characters; with groups of eight, one member may be used for error correction or other function.

 

It was in August, 1874 that he received his first patent on a telegraph code that by the mid-20th century had supplanted Morse Code as the most commonly used telegraphic alphabet.


November 12, 1877  was when the first on-line tests of his system took place between Paris and Bordeaux.  The Baudot apparatus installed at the Universal Exhibition of 1878 won him the great gold medal and the unanimous congratulations of the engineers of the entire world.

During this period of twenty years, Baudot installations multiplied in France and spread in foreign countries, everywhere assuring excellent service in doubling, tripling, or quadrupling the efficiency of the wires.

At the end of 1877, the Paris-Rome line (about 1700km), a difficult operation for the Hughes, began to be served by a double Baudot. The first telegrams transmitted were those announcing the election of Mr. Carnot to the presidency of the French Republic.

Since then, the Baudot has been installed successively between Paris and Vienna, between Paris and Berne, between Paris and Berlin, between Paris and London, and between Hamburg and le Havre. In the same time, it has been adopted for interior service in Italy, in the Netherlands, in Spain, in Brasil, etc.

In these times, Mr. Baudot solved with his apparatus the most varied and the most interesting problems.

In July, 1887, he undertook tests crowned with success between Weston and Waterville on the cable of the "Commercial" Company; the apparatus experimented with was a double Baudot installed in duplex. The Baudot transmitters and receivers were substituted purely and simply for the recorder.

On August 8, 1890, he assured, on a single wire, discrete relations between the three towns of Paris, Vannes, and Lorient, inaugurating at this date the spread-out posts that were later so much generalized.

On April 27, 1894, he established, always over a single wire, communications between the Paris stock exchange and the Milan stock exchange, and at the same time between the central Paris and central Milan, and invented for this occasion the retransmitter.

On January 3, 1894, he served with a triple apparatus the underground wires from Paris to Bordeaux that functioned painfully with the Hughes.

 

 

Here is a chart that shows all the possible Baudot combinations:

Binary

Decimal

Hex

Octal

Letter

Figure

00000

0

0

0

Blank

Blank

00001

1

1

1

T

5

00010

2

2

2

CR

CR

00011

3

3

3

O

9

00100

4

4

4

Space

Space

00101

5

5

5

H

 

00110

6

6

6

N

,

00111

7

7

7

M

.

01000

8

8

10

Line Feed

Line Feed

01001

9

9

11

L

)

01010

10

A

12

R

4

01011

11

B

13

G

&

01100

12

C

14

I

8

01101

13

D

15

P

0

01110

14

E

16

C

:

01111

15

F

17

V

;

10000

16

10

20

E

3

10001

17

11

21

Z

"

10010

18

12

22

D

$

10011

19

13

23

B

?

10100

20

14

24

S

BEL

10101

21

15

25

Y

6

10110

22

16

26

F

!

10111

23

17

27

X

/

11000

24

18

30

A

-

11001

25

19

31

W

2

11010

26

1A

32

J

'

11011

27

1B

33

Figure Shift

 

11100

28

1C

34

U

7

11101

29

1D

35

Q

1

11110

30

1E

36

K

(

11111

31

1F

37

Letter Shift

 

 

 

Sources:

http://www.enteract.com/~enf/baudot/necrologie.html

http://www.enteract.com/~enf/baudot/son-oeuvre.html

http://www.acm.inf.ethz.ch/ProblemSetArchive/B_US_EastCen/1988/baudot.htm

 

http://www.cinemedia.net/SFCV-RMIT-Annex/rnaughton/BAUDOT_BIO.html