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WHERE DID IT ALL START?
A CHRONOLOGICAL HISTORY OF THE DEVELOPMENT
OF RADIO
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| Page 3 of 6 - Samuel Morse To Heinrich Hertz |
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1832
- 1837
SAMUEL F. B. MORSE, American artist created the electric telegraph and
conceived a “code” which permitted transmission and reception of messages
over his electric telegraph. This Morse Code – was later adopted in the early transmission of
wireless messages. 1825
- 1867
MICHAEL FARADAY, English. Since it is very difficult to assign accurately
the various dates for Faraday’s inventions and discoveries the period of his
activity in this area is alternatively listed. In 1824 Faraday became a Fellow
of the Royal Institute, but his fame as a scientist had proceeded this date. He
died in 1867; and in the interim his discoveries were the most complete,
numerous and productive as any contemporary scientist’s. They deal with every
phase of the sciences, physics, chemistry, mechanics,
1865
JAMES CLERK MAXWELL, Scottish. Expressed mathematically what is known as
the “electromagnetic theory of light”, although the thought was originally
conceived by Faraday. This theory says that light (in fact all electric and
magnetic phenomena), take the form of coupled electric and magnetic waves in
motion in a mysterious substance which he called “aether.”;
1865
DR MAHLON LOOMIS,
American dentist. The inventions of the previous years had brought about
the electric generator, batteries, the wire telegraph, arc lights, a
trans-Atlantic cable and many other devices, all of which were a great boon to
humanity. But humans are always striving to improve as well as explore, and so
we find Loomis, a Washington dentist, conducting experiments and applying for a
patent on a method of transmitting and receiving intelligence using the
earth’s atmosphere as one conductor. Bingo! Radio in its most basic form seems
to have arrived, although this point is still debated today. 1875
In
1875 the microphone (or magnetic transducer, which functioned optionally
as an earphone) was invented by ALEXANDER GRAHAM BELL. About 2 years later D. E.
HUGHES invented the carbon microphone (a high output device which was still in
use up to the late 1960’s). 1879
DAVID EDWARD HUGHES, English. Discovered an arrangement which consisted
of a stick of wood covered with powdered copper; when place in an electrical
circuit the copper particles would cohere if a spark was made.
1885
SIR WM. H. PREECE and A. W. HEAVISIDE,
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electrochemistry and
electricity. His first explorations in the field of electricity resulted in the
basic principle of the electric motor. Faraday reasoned that, if an electric
current in a wire makes a magnetised needle rotate, then a magnet should cause a
wire carrying a current to do likewise. He proved his reasoning by suspending a
conductor, so that it rotated between magnetic poles. He formulated the laws of
magnetic induction, which finally led him to invent the first electric
generator; as a matter of fact he built many models, each time improving them.
He invented the induction coil, which was later improved by Ruhmkorff, a
Frenchman; and also the transformer, which operated from alternating current
and, consequently, did not need the interrupter device for starting and stopping
the current. In fact, Faraday discovered alternating current; 
and the experiment
often shown in school physics classes, for producing electricity by plunging a
bar magnet into a coil of wire, was conceived by this brilliant of all
inventors. He made a study of capacitors, discovered different dielectrics that
may be employed, and analysed the relative merits of each – finally tabulating
this data so that today we have the “dielectric constant” for each
insulating material. He coined a number electrical terms, many of which are
still in use today. Very importantly Faraday also discovered that a relationship
existed between electromagnetism and light, which was later elaborated on by
Maxwell. In his honour the unit of capacity, the “farad” was later named
after him.
the term was adopted from the Greek philosopher Encke who used the word
“ether” in 1829 while studying 
Strangely, he not
only wanted to send messages but wanted also to do away with batteries and
generators, since he was aquatinted with the fact that the atmosphere was
continuously charged with electricity. Operating on the theory that the higher
the level, the greater the charge would be, Loomis sent up kites 18 miles (29.3
kilometres) apart, from two high mountains in West Virginia. The kites, covered
with large squares of copper gauze, were connected to the ground using strings
having fine copper wire running though them. The wire from each kite was
connected to one side of a galvanometer, whose opposite side
1880 
Englishmen. These two gentlemen
sent signals to each other over a distance of 1000 yards (914 metres). The means
employed consisted of two telegraph wires paralleling each other, with a
telephone receiver (earphone) in the receiving line. The telegraph signals could
be clearly heard in the phone receiver, without actual connection between the
two, due to what is now known as “induction” or, in telephone parlance, “cross-talk”. Heaviside went on later to discover the
“ionosphere”, a layer of which was named in his honour.
1887
- 1888
opposite end of the room. When
the Leyden jar was charged sufficiently it discharged through the gap in the
wire coil; and the oscillating waves thus generated were launched into the
“ether” of the room and swept across the receiving coil causing sparks to
occur across its spark gap. Hertz measured the velocity of these waves and found
that they were the same as that of light, 186,000 miles per second (299,330
kilometres per second); also measured their length and, substantiated
Maxwell’s theories.