Transcript Telecommunication Pioneers

Telecommunication Pioneers
Day 3
Benjamin Franklin
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1747 Leydn jar was the
first capacitor
1752 discovers that
electricity has a
positive and a
negative charge
1752 flew a kite to
demonstrate
electricity and
lightening related
Luigi Galvani
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1737-1798, Italian
1780 noticed frog’s leg
jump
effects of
electrostatic stimuli
applied to the muscle
fiber of frogs
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“animal electricity”
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Inspired Volta
Count Alessandro Giuseppe
Antonio Anastasio Volta
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(1745 - 1827) Italian
1775 created the
electrophorus
1800 created the
voltaic pile
Volt named after him
Hans Christian Ørsted
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1777 - 1851, Danish
1820 a magnetic
needle is deflected at
right angles to a wire
carrying an electric
current
electromagnetic
induction
André Ampère
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(1775-1836), French
combined theory of
magnetism and electricity in early 1820's
electrical current
creates magnetic
fields
system to measure
current flow called
amperes
Georg Simon Ohm
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1787-1854, German
describes relationship between current
flow, voltage, and
resistance
Ohm’s Law
Resistance measure
Joseph Henry
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(1797-1878), American
discovered electromagnetic induction
discovered selfinductance
Inductance measure
is the Henry
Michael Faraday
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(1791-1867), British
foremost
experimental
scientist of his day
discovery of electromagnetic induction
the induction of one
electric current by
another
James Clerk Maxwell
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(1831-1879), British
mathematical basis
for electricity and
electromagnetism
propagation of
electromagnetic
waves
light is made up of
electromagnetic
waves.
Heinrich Rudolph Hertz
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(1857-94), German
demonstrates the production and detection
of Maxwell's waves
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photoelectric effect
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Frequency in Hertz
Thomas Alva Edison
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(1847 - 1931), American
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1887 creates the
carbon microphone
Guglielmo Marconi
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(1874-1937), Italian
Father of Wireless
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1894 Began work
following Hertz
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1895 short range
radio
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1899 Britain to France
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1901 Britain to Canada
Nathan B. Stubblefield
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(1860-1928), US
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1892 invents “wireless telephone”
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first person to transmit human voice
without wires
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demonstrates system officially May 30,
1902 in Philadelphia
Reginald A. Fessenden
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(1866-1932), born in
Canada of US parents
designs a highfrequency alternator
for continuos signal
1906 Christmas Eve
First broadcast of
speech & music
Lee De Forest
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(1873-1961) US
1906 Invents the
“audion” now called a
triode. Types of
vacuum tube.
key component in
nearly all radio, radar,
TV, and computers
until transistors