2. o History of communications systems
o TELEGRAPH
Definition
Who invented and when it was invented?
The working principle
Its impact
o TELEPHONE
Definition
Who invented and when it was invented?
The working principle
Its impact
3. Printing
Typewriter Telegraph Telephone Radio Computer Television Internet
Press
(1800s) (1837) (1876) (1896) (1897) (1927) (1983)
(1400)
4. Definition: Telegraph
(from Greek):
tele- means “afar, far off”
graphein- means “writing”
▶ Telegraph is an
instrument that transmits
the writings to a distant
place.
5. Before the invention of telegraph, there
were the signaling systems that people
could communicate over the long
distance.
The signaling systems were called
“semaphore” which they used flags or
lights. In this system, there was the
observer who decoded a signal from a
high tower and then sent it to the next
station.
6. In 1832, when Samuel F.B. Morse was in a ship
returning from Europe, he accidentally had an idea
of using electricity to communicate over distance.
Because in this ship, many passengers discussed
about the electromagnet which was recently
invented. After Morse entirely understood how the
electromagnet worked, he realized that sending a
code-message via a wire might be possible.
However, Morse found that this were difficult.
Thus, he asked his friend, Leonard D. Gale in order
that he could follow his idea.
Samuel Finley Breese Morse
(1791 –1872)
7. In 1837, because of the Panic which caused a long depression, Morse could
not introduce his new system although he had enough confidence to do that.
However, Morse used this time to travel to Europe not only to register a
patent but also to examine the English telegraph systems. He felt very
confident because even though his main competitor had created an
ingenious mechanism, Morse’s telegraph was more efficient and easier to
use.
Fortunately, in 1843, the economic was recovering, Morse again asked the
Congress for the cash of $30,000 in order to build the underground telegraph
line from Washington to Baltimore.
Morse hired the great construction engineer, Ezra Cornell to lay the pipe
which carried the wire. However, because of the wire was defective
insulation, Cornell suggested stringing wires overhead on trees. Morse
approved of this great idea.
Finally, the line was completed.
8. On May 24, 1844,
the first message,
“What hath God
wrought?” was sent
by the telegraph.
Sending the first telegraph message
9.
10. At first, the telegraph system progressed slowly and the system could not work
for the entire country. Thus, Morse continually tried to improve the telegraph
system as well as to extend the telegraph line. Fortunately, other companies
began to open their own systems, the telegraph system began to develop.
In 1914, automatic transmission was developed instead of trained code users
that were used in the first telegraph to transmit the telegraph messages. This
development in transmission made the message transmission much faster than
the old way.
At that time, all long distance communication depended strongly on the
telegraph.
However, when the telephone and radio were invented, the telegraph was less
develop than that in first haft of 1990s.
11. With the invention of telegraph, the
world suddenly became much
smaller.
With the invention of telegraph, the
world became more connected.
Moreover, the telegraph also
contributed to the establishment of
world peace by erasing the
national–rivalries.
12. Definition: Telephone (from
Greek):
tele- means “afar, far off ”
-phone means “sound, voice”
▶ Telephone is an instrument
that transmits sound, voice to
a distant place.
13. Before the invention of telephone, there
was telegraph which was telephone’s
precedent.
In the early 1870s, while Alexander
Graham Bell was experimenting with
telegraph, he realized that transmission
the human voice over a wire by using
electricity might be possible.
Because he lacked the skill to make the
equipment that were necessary for the
experiments, he asked Thomas A. Watson
for assistance.
Alexander Graham Bell
(1847 – 1922)
14. Bell and Watson worked together on the
experience which tried to produce sounds
over the “harmonic telegraph”.
On June 2, 1875, Bell heard the sound
coming to him over the wire.
After much tinkering, the instrument
successfully transmitted the recognizable
voice sound, but not words.
Thus, Bell and Watson spent the whole
summer to experiment.
On March 7, 1876, the patent for telephone
was issued to him.
At 109 Court Street, Boston, the first Alexander Graham Bell
understandable sentence was carried by the was working on the first
telephone
telephone.
15. The electric energy is
converted to acoustic
energy again The speedy conversion
from acoustic to electric
energy
18. At first, the telephone was extremely hard
for anyone to afford because of its price.
Only the rich could afford for telephone.
Telephone’s invention contributed to the
development of city centers and buildings.
With the invention of telephone, some jobs
suddenly became unnecessary.
In addition, the world became much smaller
and more accessible to all business
because of the telephone.
19. Time Quantity of telephones (unit)
May 1877 6
November 1877 3,000
1881 133,000
1990 600,000
1905 2,2000,000
1910 5,800,000
The statistic about the growth of telephone
20. In 1885, American Telegraph and Telephone Company (AT&T) was
formed.
The growth of telephone was extremely fast. (By 1900 there were
nearly 600,000 phones in Bell's telephone system; that number raised
to 2.2 million phones by 1905, and 5.8 million by 1910). (30 millionth
phone was connected in the U.S. by 1984, by the 1960s, there were
more than 80 million phone in the U.S. and 160 million in the world).
21. Nowadays, the telephone is an
indispensable instrument on over the world.
Telephone makes the world smaller and
bring people closer together, thus,
decreasing loneliness and building new
communities.
The invention of telephone also increase
privacy in many ways. It allows people to
exchange information without writing.
Moreover, telephone help people to
connect very fast regardless to their
distance.