Electronic Communications

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Lesson 6
Electronic Communications
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Samuel Morse 1791-1872
Samuel Morse is best known as the inventor of the
telegraph
in 1835, Samuel Morse proved that signals could
be transmitted by wire. He used pulses of
current to deflect an electromagnet.
And on May 1, 1844, the first news was dispatched
by electric telegraph.
Until 1877, all rapid long-distance communication
depended upon the telegraph. That year, a rival
technology developed that would again change the
face of communication..
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In 1840 he patented a new code that used
combinations of dots and dashes to represent all
26 letters in the alphabet and numbers from 1 to
10. It was named Morse Code                      
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The original Morse telegraph printed code on
tape. However, as the operation developed into
sending by key and receiving by ear. A trained
Morse operator could transmit 40 to 50 words per
minute.
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http//www.connected-earth.com/Playit/morsecodeand
semaphore/index.htm
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LESSON NOTES
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The word "telegraph" is derived from Greek and
means "to write far" so it is a very exact word,
for to write far is precisely what we do when we
send a telegram. The word today, used as a noun,
denotes the system of wires with stations and
operators and messengers, girdling the earth and
reaching into every civilized community, whereby
news is carried swiftly by electricity. But the
word was coined long before it was discovered
that intelligence could be communicated by
electricity. It denoted at first a system of
semaphores, or tall poles with movable arms, and
other signaling apparatus, set within sight of
one another.
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While a professor of arts and design at New York
University in 1835, Samuel Morse proved that
signals could be transmitted by wire. He used
pulses of current to deflect an electromagnet,
which moved a marker to produce written codes on
a strip of paper - the invention of Morse Code.
The following year, the device was modified to
emboss the paper with dots and dashes. He gave a
public demonstration in 1838, but it was not
until five years later that Congress (reflecting
public apathy) funded 30,000 to construct an
experimental telegraph line from Washington to
Baltimore, a distance of 40 miles.
In 1837 Samuel Morse and Alfred Vail had an
electromagnetic telegraph that would turn presses
of a key at one end into movements of a lever or
paper punch at the other. They could send and
record short and long pulses along the line - but
without any way of turning those into letters and
numbers. They needed a code and together worked
to develop it.
He developed a 'language' that translated letters
of the alphabet and numerals into individual code
'symbols' that could travel down the same wire
one after the other and be printed out at the
receiving end these formed the basis of Morse
Code. In 1844, he sent his first public message,
which read 'What hath God wrought!' The
subsequent development of a sounder device meant
that his dots and dashes could be 'read' by ear
as well as visually on paper.
The arrival of the electric telegraph in 1837
created a new reality messages transmitted very
quickly and reliably over distances farther than
a man could see. As the networks grew the
distances became greater and greater, linking
towns, then countries and finally continents.
Within 30 years the telegraph had transformed
business, commerce, government and society. But
the impact on ordinary lives was subtler.
Reuters was created by founder Paul Reuter in
1851 to deliver news and information,
specialising in financial data, using the fastest
available means, ranging from pigeon post to
express trains.The company rose to prominence by
making use of the telegraph system, particularly
bringing news into London via the Dover-Calais
submarine telegraph cable. The company sealed its
reputation by being the first to deliver the news
of Abraham Lincoln's assassination.Since then
Reuters has developed a reputation of being first
with the news. This was consistently proved with
notable 'scoops', which included the details of
the Armistice agreement that ended the First
World War in 1918, Khrushchev denouncing Stalin
in 1956, and both the construction and the fall
of the Berlin Wall.Reuters has also pioneered
new technology to deliver stories rapidly
including the use of computers, video screens,
television, wireless and the Internet.
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