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History
The development of the Radio was the culmination of a long process
bringing together the fundamentals of theoretical physics and the
experiments of a few, exceptional, engineers.
The story starts at the end of the 17th century, a time when the learned
and the wise sought to understand and explain the mysteries of the
universe and to answer the question, What is light?
... but some researchers were already experimenting with magnetism.
The first machines were developed to carry out HYPERLINK
"http://perso.club-internet.fr/dspt/Amusement.htm" experiments based
on static electricity, allowing the experimenters to become familiar
with new and spectacular phenomena, such as disruptive discharges,
electric wind and the ionisation of gas, by flame.
The English doctor, William GILBERT (1544-1603), Royal Physician to
Queen Elizabeth I and to James I, was the first to propose the idea that
the earth is an enormous magnet, and that all matter is either isolating
( nonelectrics ) or conducting (electrics).
He described his research in his book "De Magnete" (Of Magnets) the
title itself demonstrating that we are at the still at the earliest
point in the development of the exact sciences.
In the world of light and opticks the theory that light consists of
particles, based on former views, could not explain phenomena such as
diffraction and polarisation.ÂÂ
The work of Isaac NEWTON (1642-1727) and in particular, his analyses of
the decomposition of white light by a prism, contributed to the
evolution of knowledge and signalled the decline of the particle
theories.
In France, it was Voltaire who brought Newton (of whom he was a fervent
supporter) to the attention of the scientists of the day. In 1756
Voltaire wrote the preface to the translation of Principia, Newton s
major work. The translation, a remarkable work in itself, was the result
of a collaboration between Mme la Marquise du Châtelet, the
mathematician Alexis Claude CLAIRAUT (1713-1765) colleague of Pierre
Louis Moreau de MAUPERTUIS (1698-1759) another great defender of Newton
and friend of the BERNOULLI
It would take a further fifty years before the French scientists,
trapped in Cartesian dogma, acknowledged the idea of the interaction of
bodies and contributed to the development of this new theory.
Of course, Radio is not yet born, but the idea that physical action can
exist across a space, devoid of all matter, is a revolutionary leap
forward.
It is only right to note the remarkable contributions of numerous
scientists to the adoption of these new ideas, and in particular
LAGRANGE who brought together in his Maison d Arcueil the cream of
physicists of the time to discuss the basic fundamentals of modern
physics and mathematics. In this melting pot of new ideas, the wise and
famous rubbed shoulders with each other, people such as GAY-LUSSAC,
HUMBOLT, BERTHOLLET student of Lavoisier, Jean-Baptiste BIOT, Etienne
Louis MALUS were among other multi-talented, multi-disciplined chemists,
physicists, astronomers and mathematicians.
At the end of the 18th century, revolution was not only to be found in
the streets, it was in the heads as well!
The idea of the need for scientific collaboration was also born.
The Arcueil Society (La Société d Arcueil) was the first to
demonstrate that experimental science need no longer be a solitary
science. (Les Cahiers de Science &Vie - November 2001).
Charles HYPERLINK "http://perso.club-internet.fr/dspt/COULOMB.htm"
COULOMB (1736-1806) on the eve of the French revolution, wrote seven
memoirs in which he established the experimental and theoretical bases
of magnetism and static electricity.
Another noteworthy contributor is the British chemist and physicistÂÂ
Henry HYPERLINK "file:///C:\WEBSHARE\WWWROOT\CAVENDISH.htm"
CAVENDISH (1731-1810) who, among other successes, established a means
of measuring the strength of static electricity.
Around 1750, the English physicist John HYPERLINK
"http://perso.club-internet.fr/dspt/CANTON.htm" CANTON studied
electro-static induction. His conclusions brought into question the
electrical theories of the time (models based on one or two fluids)
which required the transfer of electrical fluids.
The possibility of the existence of physical phenomenon between two
bodies without direct contact, grows in acceptance.
Augustin FRESNEL (1788-1827) demonstrated that Newton s theory of
particle emission could not account for numerous phenomena.
His research with Louis HYPERLINK
"http://perso.club-internet.fr/dspt/ARAGO.htm" ARAGO (1786-1853) and
Leon FOUCAULT (1819-1868) led to the establishment of the light wave
theory (in 1820) which applied later to other electromagnetic fields.
Joseph FOURIER (1768-1830) father of mathematical physics, developed new
mathematical tools (number series and the Fourier Transform) which would
help the new physicists understand and describe the phenomena they were
observing.
Scientific discoveries accelerated from the start of the 19th century.
The Danish physicist, Christian HYPERLINK
"http://perso.club-internet.fr/dspt/OERSTED.htm" OERSTED (1777-1851)
during a long series of experiments carried out between 1807 and 1820,
demonstrated that a magnetised needle placed near to an electric
conductor will move in a direction dependent on the direction of the
flow of the electric current.
His work was quickly recognised by those at the forefront of science at
the time, particularly the French, and ARAGO, in 1820 achieved the
magnetisation of iron by use of an electric current.
1820 The year that remains, without doubt, the key date for the
advancement of physics in the field of electro-magnetism....
.... and the starting point for the invention of Radio.
HYPERLINK "http://perso.club-internet.fr/dspt/BIOT.htm" Jean-Baptiste
BIOT (1774-1862) and Felix SAVART (1791-1841) French physicists,
established in 1820, a means to measure the strength of a magnetic field
created by an electric current, thus creating the BIOT-SAVART Law.
In Germany, Johann HYPERLINK
"http://perso.club-internet.fr/dspt/SCHWEIGGER.htm" SCHWEIGGER
(1779-1857) built a multiplier which was, in fact, the first
galvanometer.
For his part, in France, Claude HYPERLINK
"http://perso.club-internet.fr/dspt/pouillet.htm" POUILLET (1790-1868)
invented the HYPERLINK
"http://perso.club-internet.fr/dspt/galvanometre.htm" "tangent
compass".
Pouillet supported the work of OHM and confirmed OHM s Law in 1834.
At the same time, the French physicist, André-Marie HYPERLINK
"http://perso.club-internet.fr/dspt/AMPERE.htm" AMPERE (1775-1836)
developed the theory of electromagnetism.
Taking the galvanometer, he invented, with ARAGO the electro-magnet, the
foundation of the electric telegraph.
He also invented the name solenoid to describe the bobbin used (from the
Greek soleinedes meaning pipe-shaped).
The electro-magnet was refined in England by William HYPERLINK
"http://perso.club-internet.fr/dspt/STURGEON.htm" STURGEON  in 1821.
The German physicist, Georg Simon HYPERLINK
"http://perso.club-internet.fr/dspt/OHM.htm" OHM (1789-1854)
discovered, in 1827, the fundamental laws governing electric currents
and defeined the concepts of resistance and resistivity
(V = R*I)
In 1831, an Englishman, Michael HYPERLINK
"http://perso.club-internet.fr/dspt/FARADAY.htm" FARADAY (1791-1867)
proposed the hypothesis of the existence of electric, magnetic and
gravitational fields between disparate objects.
He described electromagnetic induction which allows the conversion of
magnetism into electricity.
At the same time, he investigated HYPERLINK
"http://perso.club-internet.fr/dspt/TubeCrookes.htm" electrical
discharges in rarefied gases and produced evidence of the phenomenon of
ionisation.ÂÂ
The American physicist, Joseph HYPERLINK
"http://perso.club-internet.fr/dspt/HENRY.htm" HENRY (1797-1878)
perfected the electromagnet and constructed a mile long telegraph line
in 1831.
Following his work on the telegraph, he discovered, in 1832,
self-inductance.
He observed the effects of induction caused by the electrical impulses
during lightning strikes.
He managed to magnetise a steel needle placed 10 metres from his spark
generator.
Heinrich Daniel RUHMKORFF (1809-1877) German mechanic and electrician,
invented the induction coil which bears his name.
Heinrich HYPERLINK "http://perso.club-internet.fr/dspt/LENZ.htm" LENZ
(1804-1865) a Russian physicist of German origin, published, in 1833,
the law describing how induced voltage causes current to flow around a
loop (Lenz Law).
A major step towards the Wireless, has been made.
In 1832 in the United States, Samuel HYPERLINK
"http://perso.club-internet.fr/dspt/MORSE.htm" MORSE (1791-1872)
invented the telegraph and the famous "Morse Code" which would also help
to achieve the first radio transmissions.
In 1855, the British inventor David E. HYPERLINK
"http://perso.club-internet.fr/dspt/HUGHES.htm" HUGHES (1831-1900)
added a magnetically operated stylus with which the signals were
recorded on a roll of paper tape, making the machine much more
functional.
One of the first steps towards the Wireless is without doubt, the
demonstration of the potential use of an earth return for the telegraph.
Following the work of Carl August von STEINHEIL (1801-1870) a German
physicist who built the first public telegraph between Nuremberg et
Fürth around 1838, the possibility of a telegraph link using a single
cable over long distances was confirmed and from 1842, MORSE installed
the first single cable lines in the United States.
The phenomenon of electrical induction continued to fascinate numerous
researchers, doctors and scientists.
In 1854, James Bowman HYPERLINK
"http://perso.club-internet.fr/dspt/LINDSAY.htm" LINDSAY (1799-1862) a
Scottish electrician, patented a wireless telegraphy system  using
water as a conductor.
The development of more and more powerful RUHMKORFF coils, allowed
researchers to push their experiments further and further, often in
physics laboratories bearing RUHMKORFF s name where the coil had become
an indispensible piece of equipment.
Such experimental HYPERLINK
"http://perso.club-internet.fr/dspt/laboratoires.htm" laboratories
were built in Europe and the United States.
In 1858 Wilhelm FEDDERSEN (1832-1918) German physics professor at
LEIPZIG demonstrated experimentally that the sparks jumping between the
spheres of a RUHMKORFF coil oscillated and that they could generate
electric waves of long wavelength.
In 1861, he used the rotating mirror designed by British physicist
Charles WHEATSTONE (1802-1875) to record the phenomenon on a
photographic plate.
The propogation of these waves, as with light waves, happens in all
directions.
The figure opposite, shows the pattern of these oscillations. Their
short lifespan fascinated Helmholtz.
In 1864, James HYPERLINK
"http://perso.club-internet.fr/dspt/MAXWELL.htm" MAXWELL (1831-1879)
inspired by the works of FARADAY, united electric and magnetic phenomena
in his famous electromagnetic theory of light.
MAXWELL s theory was used by HYPERLINK
"http://perso.club-internet.fr/dspt/hertz.htm" HERTZ (1857-1894) to
discover the waves that now bear his name.
MAXWELL s theory is complex and its mathematical presentation difficult
to understand.
It would probably not have been so readily accepted by the scientific
community of the time, had it not been for the support of certain
enlightened physicists.
Among MAXWELL s most fervent supporters, we should mention George
Francis FITZGERALD (1851-1901) Professor at Trinity College, Dublin,
who, through his Presidential Address to the Mathematical and Physical
Section of the British Association for the Advancement of Science in
1886 made, without doubt, a major contribution to the recognition of the
works of MAXWELL and HERTZ and later, researchers like Oliver LODGE.
In 1882, FITZGERALD, in his paper to the Royal Dublin Society, On the
Possibility of Originating Wave Disturbances in the Ether by Means of
Electrical Forces, presented the idea that it only needed the
construction of an electromagnetic wave generator of sufficient power to
convince the entire scientific community of the revolutionary character
of MAXWELL s theory.
In 1866, the American Mahlon HYPERLINK
"http://perso.club-internet.fr/dspt/LOOMIS.htm" LOOMIS (1826-1886)
experimented with a system for transmitting electrical signals in the
atmosphere between two kites covered with copper wire screens, linked to
a galvanometer and 18 miles apart.
The Wireless is almost reality!
LORENZ microscopic theory of matter which links up with the macroscopic
MAXWELL theory, explains a great number of phenomena such as the
electrical conduction of metals, chromatic dispersion of light, or the
influence of magnetic fields on the dispersion of rays and even gives a
new vision of ether .
Progressively, man passes from the mechanical view of his environment to
an electronic view of matter in which mass and time are nothing but the
displacement of quantum energy.
EINSTEIN arrives on the scene with his Theory of Relativity (1905) which
throws scientific understanding into disarray and gives birth to modern
physics.
But, the theories would be worthless without the ingenuity of the
inventors and researchers.
Thomas Alva EDISON (1847-1931) American inventor, perfects the
HYPERLINK "http://perso.club-internet.fr/dspt/La_lampe.htm"
incandescent light (1878) and recognises HYPERLINK
"http://perso.club-internet.fr/dspt/Edison.htm" thermo-electron
emissions (1881).
In 1878 David Edward HUGHES invented the HYPERLINK
"http://perso.club-internet.fr/dspt/Microphone.htm" microphone .
Some years later, in 1888, Nikola HYPERLINK
"http://perso.club-internet.fr/dspt/TESLA.htm" TESLA  conceived the
first operational system for the generation and distribution of
alternating current for the electricity networks (grids).
From 1890 Edouard BRANLY (1844-1940) professor at the Institut
Catholique de Paris investigated the experiments of Hertz.
IN 1890, he perfected the HYPERLINK
"http://perso.club-internet.fr/dspt/branly.htm" "tube radioconducteur"
 used as a receiver for a Hertz oscillator.
The photo opposite shows the first "receiver" developed by Branly.
The "radioconducteur" is on the left of the image. It is connected, in
series to a battery and a galvanometer.
At rest, the needle is at zero.
Under the effect of an electromagnetic disturbance (spark) the needle
moves.
In Italy, Augusto HYPERLINK
"http://perso.club-internet.fr/dspt/RIGHI.htm" RIGHI , physics
professor in Bologna, was also investigating electromagnetic waves and
repeated Hertz experiments using a modified oscillator.
In Britain, Sir Oliver HYPERLINK
"http://perso.club-internet.fr/dspt/LODGE.htm" LODGE (1851-1940) a
professor at the University of Liverpool, took up, in 1894, the work
carried out by Hertz and Branly. He perfected Branly s radio wave
detector, adding to it a mechanical shock device to bring the detector
back to its resting state. He called the device a "coherer".
In 1894, LODGE demonstrated, for educational purposes, the transmission
and detection of radio waves over a distance of approximately 30 metres.
He didn t recognise the significance of his achievement, but from this
point, things would advance very rapidly.
The same year, Eugene TURPAIN (1848-1927) a French chemist, carried out,
in BORDEAUX, the first radio telegraphy experiment, transmitting a
message by radio waves.
The Russian, Alexandre Stepanovitch HYPERLINK
"http://perso.club-internet.fr/dspt/POPOV.htm" POPOV (1858-1905) a
professor of civil engineering, built, in 1895, a device designed to
measure electrical disturbance in the atmosphere. He was the first to
perfect transmission and reception devices and invented the HYPERLINK
"http://perso.club-internet.fr/dspt/Lantenne.htm" aerial .
HYPERLINK "http://perso.club-internet.fr/dspt/DUCRETET.htm" Eugene
DUCRETET (1844-1915) manufacturer of scientific precision instruments,
then radios, then X-ray machines, also built machines (1887) to
reproduce the experiments carried out by Hertz.
Jules CARPENTIER (1851-1921) former engineer with the French railway
company PLM, after taking over from RUHMKORFF, manufactured the first
Branly radio wave detector tubes in 1900.
In Italy, Guglielmo HYPERLINK
"http://perso.club-internet.fr/dspt/marconi.htm" MARCONI (1874-1937) a
student of RIGHI, was pursuing his passion for electricity and
electromagnetism.
In France, engineer Gustave HYPERLINK
"http://perso.club-internet.fr/dspt/ferrie.htm" FERRIE (1868-1932) was
developing the interest he had had in wireless since 1898.
In 1904 John HYPERLINK
"http://perso.club-internet.fr/dspt/fleming.htm" FLEMING (1849-1945)
connected an oscillating circuit to the plate of an EDISON tube. He
noted that the galvanometer, connection in series, registered a
deviation during a radio transmission.
He patented his Oscillation Valve system in November 1904.
He had the valves manufactured and they were baptised "diodes" by Dr
W.H. ECCLES.
FLEMING did not invent the diode, EDISON takes the credit for that, he
simply introduced a plate into the tube and applied the EDISON effect to
create a rectifier and detector.
The studies of DRUDE, SLABY and WIEN led, in 1905, to an improvedÂÂ
understanding of the behaviour of radio waves.
Lee HYPERLINK "http://perso.club-internet.fr/dspt/DE_FOREST.htm" DE
FOREST (1873-1961) working since 1903 on detectors, decided, in 1907,
to introduce a polarising battery, in the anodic circuit of a FLEMING
valve. This modification made the valve much more sensitive.
On the 15th January 1907, DE FOREST applied for a patent on the new
tube which he called " HYPERLINK
"http://perso.club-internet.fr/dspt/Audion.htm" AUDION "..
On the 29th January, he applied for a further patent regarding the
introduction of a third electrode, placed between the filament and the
anode.
This semi-opaque electrode, was called a grid  because of its
interwoven structure, and to distinguish it from the plate which was
formed from solid material.
The HYPERLINK "http://perso.club-internet.fr/dspt/Triode.htm" triode
was born.
Lee de FOREST also had the idea to link this electrode to a circuit
connected to an aerial. The signal heard in the headset placed in the
anode circuit was stronger than that heard with a simple diode. He had
invented the first electronic amplifier.
Reginald HYPERLINK "http://perso.club-internet.fr/dspt/Fessenden.htm"
FESSENDEN (1866-1932) a Canadian and former collaborator of EDISON, had
the idea of overlaying two high frequency radio waves to carry low
frequency audible waves - speech. He also invented a detector sensitive
enough to be used in radio telephony.
In 1906 he built a powerful transmitter in Massachusetts.
RADIO is born !
The industrial production of the triode in Europe and the US was quickly
established. The production of these first valves was made strategically
important with the declaration of the First World War.
The first valves produced were reserved exclusively for military use.
In 1908, the workshops of Carpentier, Gaiffe and Rochefort formed the
Compagnie Générale de Radiotélégraphie (C.G.R.) of which Professor
d’ARSONVAL became president.
The Minister for War, ordered three transmission stations; Belfort, Toul
and Verdun, from C.G.R.
Emile GIRARDEAU (1882-1970) engineer, on the 3rd April 1910 formed the
Société Française Radioélectrique with BRANLY as Technical Director,
to build wireless equipment. The leading French manufacturer in 1920, he
created a subsidiary company to exploit the transmitters of Saint
Assise, known as "RADIO FRANCE".
Valdemar HYPERLINK "http://perso.club-internet.fr/dspt/POULSEN.htm"
POULSEN (1869-1942) built continuous wave transmitters using arc
transmitters according to the principles proposed by William DUDDELL .
From 1912 a regular wireless service was operational between San
Francisco and Hawaii.
In 1914, the Germans installed a military radio station at Kamina in
Tongo.
Research now turned to the elimination of arcs and their harmonics by
use of HYPERLINK
"http://perso.club-internet.fr/dspt/alternateurhf.htm" ALTERNATORS .
The first of these machines turned at 3000rpm. Power output was in the
range of 250 to 500 kW. A frequency of 15000Hz to 20000Hz corresponding
to wavelengths of 20000 to 15000 metres.
To reduce the wavelength, it was necessary to develop frequency
doublers, triplers and even quadruplers which still generate wavelengths
of the order of 3500 to 5000m.ÂÂ
FESSENDEN had the idea of mixing a low frequency signal with a high
frequency carrier wave.
He called this the HETERODYNE system.
At the same time, it was discovered that a coil, inserted in series in
the plate of the triode and coupled to a coil in the grid circuit,
could, under certain conditions, generate an auto-oscillation which in
turn generated radio waves. This configuration opened up numerous
possibilities in the field of transmission.
The triode was used in all the fundamental radio functions, low
frequency amplification, high frequency detection and as an oscillator.
Industrial developers desparately sought improvements in selectivity and
sensitivity of their receivers and proposed more and more elaborate
models.
The early propositions had, nevertheless, the inconvenience of having
as many tunable circuits (variable condensors and induction coils) as
amplifiers, that there were often several knobs to be turned to change
station.
And, the increase in amplification created instability in the receivers
which were subject to sticking (auto-oscillation) making their use even
more delicate and their functioning haphazard.
This problem would be solved by improvements in the characteristics of
the components and by the implementation of NEUTRODYNE circuits.
In 1914, the Austrian engineer, Alexsander MEISSNER (1883-1958)
developed the principle of a "super heterodyne" assembly.
In 1917 in France, Lucien HYPERLINK
"http://perso.club-internet.fr/dspt/LEVY.htm" LEVY created and
perfected the " HYPERLINK
"http://perso.club-internet.fr/dspt/Superheterodyne.htm"
SUPERHETERODYNE " assembly, still in use today. He deposited 2 patents,
one the 4th July 1917, the other the 1st October 1918.
Still in 1917, thanks to American engineer Edwin Howard HYPERLINK
"http://perso.club-internet.fr/dspt/AMSTRONG.htm" Armstrong , we see
the development of the triode, turning it into an autodyne receiver,
reactive receiver and a transmitter  .
At the end of the First World War, in 1918, construction of the first
continuous wave transmitters, using triodes, started.
The early spark transmitters, based on Marconi principles, and which
transmitted coded information (time and weather information) directed
towards navigatory and military applications, were still in use at the
time, but, their days were numbered.
They were rapidly overthrown by continuous wave transmitters capable of
transmitting music and the human voice.
Between 1916 and 1919, the wireless became the RADIO with the
introduction of valves.
It was the end of the electric period and the start of the electronic
age.
With the end of hostilities, the political powers in France, and
elsewhere, pushed by industrialists, were quick to understand the
benefits of developing public radio broadcasting.
In the HYPERLINK "http://perso.club-internet.fr/dspt/RadioUS.htm"
United States and in HYPERLINK
"http://perso.club-internet.fr/dspt/RadioCanada.htm" Canada the first
commercial Radio stations were born, trasnsmissions were planned and
organised - programmed.
On the 26th November, 1921, the first French public radio broadcast was
made.
In the premises of the new and powerful radio station of HYPERLINK
"http://perso.club-internet.fr/dspt/Sainte_assise.htm" SAINTE-ASSISE ,
near Melun, an opera singer, mademoiselle Yvonne Brothier, stood,
surrounded by technical transmission equipment, and sang "la
Marseillaise", la "Valse de Mireille" and an extract from "The Barber of
Seville".
Forty kilometers away, members of the Société Amicale des Ingénieurs
Electriciens, gathered together for a banquet at the Hotel Lutetia in
Paris, heard the singer s voice with "a great intensity and perfect
clarity." Enthusiasm was not in short supply.
The concert was heard on numerous radios, both French and foreign,
within a radius of 1600 kilometers.
The number of listeners was still very low, radio reception being
limited to members of a "switched on" public.
In February 1922, Emile GIRARDEAU returning from the USA, proposed the
creation of a public service, broadcasting news and music.
French Radio is born !
On the 14th November 1922, in England, the BBC started broadcasting.
Starting in PARIS, then spreading to the larger cities throughout
France, fans of classical music and operetta could listen to their
favourite works in their own homes.
Staring in this year, 1922, the SFR station in Levallois-Perret (2kW
output) gave daily concerts on 1525m between 8:45 and 10:00 in the
evening, as well as a concert every Sunday at 2pm.
The HYPERLINK "http://perso.club-internet.fr/dspt/LADOUA.htm"
LYON-La DOUA station broadcast every morning at around 10:30, on a
frequency of 1600m, a radio message which started, "This is the
Radiotelegraphy station of the LYON Post and Telegraph Administration."
Radio culture, reserved up until now for a minority of intellectuals,
would finally break into the homes of the more humble listener.
In France, almost everyone knows the tune, from the operetta, "LE PAYS
DU SOURIRE" called "Je t ai donné mon coeur" sung by Rudy Hirigoyen. A
tune which excited the hearts of many French people early in the 20th
century.
Click on the phonograph to hear an extract of this song.
The first speaking newspapers appeared, as well as the laws on the right
to install a radio transmitter. It must be remembered that this was
still very soon after the First World War and that the politicians
clearly understood the strategic implications of Wireless.
Marcel PELLENC (1897-1972) Director of the "Ecole superieure des PTT",
(the training college for the French Postal administration) brought into
operation, on the 19th January 1923, within the college, 103 rue de
Grenelle, PARIS, the first medium wave radio in Europe.
Rene HYPERLINK "http://perso.club-internet.fr/dspt/MESNY.htm" MESNY
(1874-1949), who, during the 1920s had joined the team of General
FERRIE, established, with the help of Georges BEAUVAIS, a VHF radio link
between mainland France and Corsica in 1926.
The management of the airwaves (the right to broadcast and the
allocation of frequency ranges to different users) became an
international preoccupation which led to the creation of the
International Telecommunication Union (ITU) whose role was, and remains,
to produce new legislation and coordinate the necessary management
organisations.
The first long distance radio transmission experiments over short wave
or ultra-short waves brought out the phenomena of signal HYPERLINK
"http://perso.club-internet.fr/dspt/Propagation.htm" propagation in
space and the possibility of using line of sight broadcasting, or
bouncing signals off the upper atmospheric layers, depending on the
wavelength used.
The first reviews popularising the new techniques also appeared and were
devoured by a hungry public. A public, still bearing the scars of war,
enthusiastically welcomed the efforts of radio pioneers like HYPERLINK
"http://perso.club-internet.fr/dspt/ROUSSEL.htm"  Joseph ROUSSEL who,
in France, threw himself into a public awareness campaign, organising
radio clubs, conferences and writing high quality books.
Everything was now, finally, ready for mass development of the RADIO.
ooOoo
It can be said that from 1922-3, radio moved out of the hands of the
pioneers, and into our everyday lives.
Radio has become a permanent feature of our environment. With the advent
of radio, came the communication era, the information era, even the
dis-information era.
In 1924, the American Presidential Election campaign was broadcast
across the country for the first time. The wireless was without doubt, a
success factor for Republican candidate John COOLIDGE who became, thanks
to the power of this new media, the 30th President of the United States.
Radio became, within a few decades, a commodity coveted by all powers,
but particluarly by political powers (remember the use of radio by the
3rd Reich for the broadcast of NAZI propaganda).
ooOoo
When we talk about international communication, we must also consider
understanding, and the problems of language...
The problem did not escape the thinking of the early pioneers. Marconi
himself, in the magazine LA MOVADO ( HYPERLINK
"http://perso.club-internet.fr/dspt/esperantoorg.htm" ESPERANTO
magazine) September 1926 issue, noted that "the largest superiority that
man has over the animals, is his ability to communicate in detail, his
thoughts to his fellow creatures."
It is no real surprise that the pioneers of radio, such as Doctor Pierre
CORRET (shown opposite) were interested on the one hand in the
development of a common language of communication on a global scale, and
contributed to the spread of the international language, ESPERANTO, and
on the other hand, worked on the popularisation of Radio, a medium for
communicating that language.
During the 1920s, Dr Corret was vice-president of the Society of Friends
of Radio and member of the International Esperantist Academy.
He was also one of the first French HYPERLINK
"http://perso.club-internet.fr/dspt/RadioAmateur.htm" amateur radio
enthusiasts (call sign 8AE).
It was perhaps no accident that the first International Congress on
ESPERANTO, presided over by its inventor, Dr Louis Lazard HYPERLINK
"http://perso.club-internet.fr/dspt/ZAMENHOF.htm" ZAMENHOF , took place
in 1905 at Boulogne-sur-mer near to Wimereux where MARCONI had installed
a wireless station some years before.
The journey s ended, but the story continues.
Remember ...
"science sans conscience n est que ruine de l âme"(Francois Rabelais).
ì¥Â`