The Vacuum Tube that Changed the World
When thinking about the future of the Internet, a lot of people make comparisons
to radio. The consensus seems to be that right now, the Internet is
about equal to radio in the late 1920s, and early 1930s. Back then,
everyone seemed to know that radio would take off and change things,
but few people had an idea of it's full potential. Interestingly enough,
however, radio and computers actually share a common ancestor: the
Audion. The Audion is the original name of the vacuum tube that Lee
De Forest invented for AT&T, back when it was still American Telephone
and Telegraph Company. The invention of the Audion helped make it possible
for Alexander Graham Bell, who was in in San Francisco, to call Watson
in New York. But that was just the beginning -- soon the Audion would
find its way into other devices, and pave the way for the future of
electronics.
Besides their use in telephone, Audion vacuum tubes became a useful way
to boost radio signals. They were eventually used in televisions and
even the ENIAC (electronic numerical integrator and computer) ballistics
computer. At its peak, ENIAC used over 19,000 vacuum tubes, also known
as triodes, to power its calculations.
De Forest's remarkable invention did marked a major transition
point in the history of electronics. When he inserted a
small coiled grid into the center of an ordinary vacuum
tube, it paved the way for the future of telephone, radio,
television and computing. What he did was relatively simple
by today's standards. He found that by regulating the voltage
that went into the grid he could boost the amount of current
flowing through the tube. That meant, instead of having
a telephone signal fade out after just 1200 miles, Audions
could be set up across the country, and boost the audio
signal enough to go from coast to coast, over 3000 miles.
Audion vacuum tubes would continue to be used in radios until the early 1950s.
That's when a new technology would take hold, making radios lighter,
smaller, and more portable. As we will see in the next What's in the
News article, this new technology changed the world of electronics
once again, and today, almost any audio or visual electronic device
we use relies on this electronic wonder.
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see what we can do. Good-bye for now, Carlos. About
the author.
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