Invention of Radio
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 successfully 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 de Forest
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 ice-field 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 commercial
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 amateurs. But de Forest 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 such as 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
1926
Silvertone
Receiver
this page written and copyright ©
Pamela E. Mack
History
122
last updated 10/28/2005