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1940
|
FM Police Radio Communications begin
in Hartford, CT
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|
1941
|
The Japanese attack on Pearl
Harbor affects the telephone system of
the United States by causing tremendous
traffic peaks in all cities,
and an increase from 100 to 400 percent
in long distance telephoning
- which already is at a record high of 3
million messages. (The
United States would again experience
this phenomenon in 2001,
during the 11 September attacks.)
Radar
successfully detects the attack on Pearl
Harbor, but the warnings are ignored.
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|
1942
|
The first section of
telephone line is completed along the
Alcan Highway, from
Edmonton, Alberta, to Dawson Creek,
British Columbia. The Alcan
Highway begins at Dawson Creek.
|
|
1943
|
Construction of a telephone
line from Calcutta, India to Kunming,
China, along Stilwell Road, begins at
Ledo, Assam.
|
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1944
|
A telephone submarine cable
is laid across the English Channel.
|
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1945
|
Western Union installs the
first commercial radio beam system.
|
|
1946
|
Mobile telephone service is
placed into commercial use in St.
Louis, Missouri.
The beam traveling-wave tube
is announced by Bell Telephone
Laboratories. This tube is an important
amplifier for broadband communication.
|
|
1947
|
Invention of the point
contact transistor by Brattain and
Bardeen at Bell Labs in
Murray Hill, NJ. (23 December)
Demonstration of mobile
telephone equipment from a United
Airlines plane to ground stations.
|
|
1948
|
Invention of the junction transistor.
|
|
1949
|
The volume of telephone
calls reaches 180 million a day!
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