|Alexander Graham Bell
became interested in the electrical transmission
of speech due to an interest in helping deaf
people learn to speak. His experiments led to
development of the telephone, for which he
received a patent on March 7, 1876.
|Lee De Forest
invented a vacuum tube that could amplify a weak
electrical signal, in 1907. The Audion, as he
called it, proved to be the fastest electronic
switching element of the time, and would not be
improved upon until the invention of the
transistor in 1948. He was also the first to use
the term "radio" instead of
"wireless telegraphy," and developed a
process for recording sound on movie film.
Farnsworth began working on what
became the television while still in high school.
On September 7, 1927, he and a small group of
investors watched as his system transmitted its
first crude image.
|Samuel Finley Breese
Morse struggled for many years to
gain recognition as a painter, but became better
known for the telegraph, which he successfully
demonstrated to Congress and the public on May
was an undertaker who had become frustrated over
human telephone operators misdirecting calls from
his customers. Determined to get rid of the need
for human operators, he invented the automatic
telephone exchange in 1891, and the dial
telephone in 1896.
The first telegraph link between North America
and Europe was completed in 1858. Unfortunately,
the cable failed within a month. Another cable
was laid in 1866, and this one proved permanent.
1 was the world's first
communications satellite capable of relaying
signals. Launched from Cape Canaveral on August
12, 1960, it relayed the first live voice
communication via satellite, the first
coast-to-coast telephone call, and the first
image transmitted via satellite. One of its
receiving antennas also picked up the first solid
evidence of the Big Bang.
was the first active
communications satellite. It was launched from
Cape Canaveral on July 10, 1962. It relayed its
first live television pictures -- of a flag
outside its ground station in Andover, Maine --
on the date of its launch, and relayed the first
live transatlantic television signal on July 23.