Telecommunication Pioneers

1
Telecommunication Pioneers

• Day 3

2
Benjamin Franklin

• 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

3
Luigi Galvani

• 1737-1798, Italian
• 1780 noticed frogs leg jump
• effects of electrostatic stimuli applied to the
  muscle fiber of frogs
• animal electricity
• Inspired Volta

4
Count Alessandro Giuseppe Antonio Anastasio Volta

• (1745 - 1827) Italian
• 1775 created the electrophorus
• 1800 created the voltaic pile
• Volt named after him

5
Hans Christian Ørsted

• 1777 - 1851, Danish
• 1820 a magnetic needle is deflected at right
  angles to a wire carrying an electric current
• electromagnetic induction

6
André Ampère

• (1775-1836), French
• combined theory of magnetism and elec-tricity in
  early 1820's
• electrical current creates magnetic fields
• system to measure current flow called amperes

7
Georg Simon Ohm

• 1787-1854, German
• describes relation-ship between current flow,
  voltage, and resistance
• Ohms Law
• Resistance measure

8
Joseph Henry

• (1797-1878), American
• discovered electro-magnetic induction
• discovered self-inductance
• Inductance measure is the Henry

9
Michael Faraday

• (1791-1867), British
• foremost experimental scientist of his day
• discovery of electro-magnetic induction
• the induction of one electric current by another

10
James Clerk Maxwell

• (1831-1879), British
• mathematical basis for electricity and
  electromagnetism
• propagation of electromagnetic waves
• light is made up of electromagnetic waves.

11
Heinrich Rudolph Hertz

• (1857-94), German
• demonstrates the pro-duction and detection of
  Maxwell's waves
• photoelectric effect
• Frequency in Hertz

12
Thomas Alva Edison

• (1847 - 1931), American
• 1887 creates the carbon microphone

13
Guglielmo Marconi

• (1874-1937), Italian
• Father of Wireless
• 1894 Began work following Hertz
• 1895 short range radio
• 1899 Britain to France
• 1901 Britain to Canada

14
Nathan B. Stubblefield

• (1860-1928), US
• 1892 invents wireless telephone
• first person to transmit human voice without
  wires
• demonstrates system officially May 30, 1902 in
  Philadelphia

15
Reginald A. Fessenden

• (1866-1932), born in Canada of US parents
• designs a high-frequency alternator for continuos
  signal
• 1906 Christmas Eve First broadcast of speech
  music

16
Lee De Forest

• (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