Invention of Radio
Radio is another example of technology shaped by
both science and values that changes our experience of the world.
Radio started out as a hobby--part of the emphasis on the new
technological world available to everyone
It is also an example of an invention
Note that Radio
was
initially imaged as a wireless telegraph; the idea of broadcasting
was a separate invention
The Wireless Telegraph:
- based on the work of physicists such as
Faraday going back to the late 1820s--some people had seen the
possibility of wireless telegraphy, but had not been able to
transmit (via induction) for more than a mile or two. James
Clerk Maxwell and Heinrich Hertz developed the theory
of electromagnetic waves. Hertz even detected them with a
spark, but it took Lodge's coherer (iron filings that
organized themselves to conduct electricity when hit by
electromagnetic waves) before this was something usable.
- Guglielmo
Marconi used sparks to create radio waves. He grew
up in Italy the son of an Italian father and a Scotch-Irish
mother, got a mostly informal education (he got permission to
sit in on university classes and work in a laboratory but did
not actually enroll as a student), and decided to devote
himself to make wireless telephony practical. This took
a lot of trial and error, but by 1895 he had a system that
would transmit many miles. His mother was convinced of
the potential and took her son to England, where she thought
the market would be better. The family decided to form
their own company, which set out to get patents
all over the world, and to publicize the new invention by
publicity stunts. In 1899 Marconi sucessfully linked
England and France across the English channel (where there was
already a cable)--more significant was transmission from
ships.
- there was a great deal of journalistic
enthusiasm for the idea of a wireless telephone--both
providing communication where there were no lines and breaking
the monopoly of the telephone and telegraph companies.
Marconi transmitted signals across the Atlantic in 1901.
He then set out to build and protect a business, for example
insisting that his stations not communicate with ships using
rival apparatus--much to the displeasure of the newspapers who
were customers.
Marconi
(left)
at
time of first successful transatlantic test
- The PR was good but the market was limited,
except for shipping and the military potential (and
interference limited the number of signals that could be
carried--you quickly got crowding between military, amateurs,
and wireless telegraphy companies). Newspapers picking
up military broadcasts and amateurs making up disasters for
fun raised the need for regulation.
- Lee
de
Forest , trained at the scientific school at Yale and
determined to be an inventor, set out to compete with Marconi
in building a wireless system. He was good at publicity
but the business claimed more than it could deliver. De
Forest was successful sued for stealing a key idea from
Reginald A. Fessenden. De Forest lost this
company, but kept rights to an invention called the Audion,
the first vacuum tube amplifier. This made it practical
to transmit the human voice instead of Morse Code. In
1907 he successfully transmitted the human voice. He did
some experiments with broadcasting, but his company collapsed
and he was accused of stock fraud.
- Edwin
Howard Armstrong started as a teenager as a radio
amateur, was a star student in electrical engineering at
Columbia. In 1912 he figured out how to improve
the audion dramatically (he understood it, which deForest
never had). In 1914 Armstrong demonstrated his idea to
the Marconi Company, where David Sarnoff realized its
importance.
artist's rendition of the sinking of the Titanic
Towards a larger market:
- When the Titanic his an iceberg on April 15,
1912, one of the ship's wireless operators immediately began sending
distress signals .
- These were picked up in New York and by
two other ocean liners about 12 hours away, but nearby ships
did not get the message because their wireless operators
were asleep, and it took the Titanic less than 3 hours to
sink.
- The California was less than 20 miles
away, but the wireless operator was asleep and the wireless
wasn't operational anyway because the captain had shut down
the engines for the night rather than try to move in an
icefield in the dark. If the California had heard the
distress signal almost all the passengers could have been
saved.
- Another ship, a freighter, was within 30
miles, but did not have a wireless at all.
- Only one nearby ship--the Carpathia, 58
miles away--got the message, only because its operator went
back to the wireless room to check a time signal after he
had finished his work for the evening.
- Once the tragedy was know, amateurs filled
the airwaves with inquiries and cruel rumors (possibly
because they had lumped together the message that the
Titanic had hit an iceberg and another message about a
different ship being towed to shore). One of the
results of the disaster was radio regulation, licensing
amateurs and limiting them to wavelengths of 200 meters or
less.
- lifting of
patent restrictions in WWI led to an explosion of
innovation of devices using vacuum tubes
- GE had bought Marconi, Westinghouse had key
circuit patents--you needed cross-licensing in order to make
anything
- In 1911 AT&T turned their laboratory
into an Industrial Research Laboratory
- bought Lee de Forest's patent on the
audion and used it for amplification of telephone lines, but
also thought they might get into what they called wireless
telephony as a feeder for the telephone system
- AT&T finally got out of the radio
business by trading for new patents they needed to keep
their monopoly on the telephone.
- the Navy was frustrated with dealing with
British Marconi patents, which meant cooperating with the
British government more than they wanted. So they
encouraged GE, AT&T and Westinghouse to form the Radio
Corporation of America in 1919. The goal was to
compete with foreign domination of international transmission.
- RCA inherited from the Navy and the Marconi
company a focus on the model of point to point communication.
- but
David Sarnoff , who even before the war had been made
head of advanced technology at Marconi, already believed in
the potential of broadcasting. Sarnoff was the
businessman who made radio commercially feasible, a poor
immigrant who became president of RCA.
The invention of broadcasting:
- Westinghouse had another idea, started commerical
radio broadcasts in 1920--a real leap of imagination
- Some amateurs had already started
broadcasting between 1913 and 1915--it was like having you own
web page, and also a good activity for high school and college
radio clubs. When de Forest sold his patent rights to
AT&T he kept the rights to broadcast news and music,
something that AT&T thought was a frivolous activity for
amatrs. But deForest dreamed of bringing concert
performances (and particularly opera) to the homes of people
who couldn't attend. In Oct 1916 he broadcast the
Yale-Harvard football game and the presidential election.
- When the U.S. declared war on Germany the
government tried to close down all amateur radio stations (and
get the operators into the military, which was very short on
operators). When the war ended the operators wanted to get
back to their hobby, and were unhappy about the ban on
transmitting that remained in effect for almost a year after
the war.
- Once the ban was lifted amateurs like Frank
Conrad in Pittsburgh began to move towards a commercial
station--broadcasting music on a regular schedule and then
getting records for free from a local merchant in return for
mentioning the store's name on the air. A local department
store began advertising and selling simple receivers to listen
to Conrad's broadcasts. And it happened that Conrad's
day job was working for Westinghouse.
- Westinghouse was making money selling to the
amateur market, and began to realize that this was not just a
few technology enthusiasts. The vice president of the
company saw a newspaper story about Conrad's broadcasts, and
the company decided they might sell more radio sets if they
broadcast on a regular basis--Nov. 2, 1920 they broadcast
election results. This got popular enthusiasm, and by
1922 a large number of stations were set up by amateurs and by
department stores, newspapers, and the companies that made
radios. A radio boom started getting attention from the
press in 1922.
KDKA
station, Pittsburgh
- But how do you get people to pay?
First companies started sponsoring entertainment--the Ivory
Soap singers--and that eventually evolved into advertising.
- There was talk of government patronage or a
licensing fee to fund broadcasting, but that sounded too
socialistic. In 1922 an AT&T run station in New York
ran a 10 minutes advertisement for a Long Island real estate
developer. As stations found ways of financing
themselves the boom spread--at one point in the 1920s 1/3 of
the sales of furniture was actually radios. ( women
in radio )
- 1926 Sarnoff helped created the first
broadcasting network, NBC.
- for more information A
timeline of radio or an excellent documentary: Empire of the Air
1926
Silvertone Receiver
this page written and copyright © Pamela E. Mack
History
1220
last updated 10/10/16