Almon Strowger, an American engineer, constructed the first automatic
telephone switching system, which had a horizontal, bladelike contact
arm, in 1891. The first commercial switchboard based on his invention
opened in La Porte, Indiana, a year later and was an instant success with
business users. To access the system, the caller pressed buttons to reach
the desired number and turned the handle to activate the telephone
ringer. During the same year, Strowger's step-by-step call advancement
technology was implemented in the long-distance service between New
York and Chicago when it proved to have the capacity of carrying
signals through cable-joint extensions.
The first actual dial telephones, patented by Lee De Forest in 1907, were
installed in Milwaukee in 1896. In 1912, their sound transmittal
apparatus adapted an electronic tube to function as an amplifier.
Transatlantic radio-telephone service linked New York and London in
1927. However, the long distance coaxial cable. which was hailed as
unprecedented, came on the scene in 1936 connecting New York and
Philadelphia. The Bell Laboratories research facility came up with the
transistor to replace the cumbersome vacuum tube, thus diminishing the
size of the electronic switch system to about 10 per cent of that of the
original. Crossbar switching, installed in terminals in 1938, operated on
the principle of an electromagnetic force, which rotated horizontal and vertical bars within a rectangular frame and brought contacts together
in a split second. A technological break-through in the form of underseas
cables between the United States and Hawaii was implemented almost
twenty years later. An extension was connected to Japan in 1964.
65. Which of the following would be the best title for the passage?
The Patent History of the Telephone
A link between Research and Technology
The Telephone: A Technological
The Developing Sophistication of the Telephone
66. It can be inferred from the passage that initially telephones ...
utilized human operators.
did not have a bell.
were limited to businesses.
revitalized business in La Porte, Indiana.
67. Why did Strowger's switchboard find application in long-distance
lines?
It could carry connections through cable extensions.
It could handle a large volume of simultaneous calls.
It required the caller to activate switches.
It was prevalent in commercial enterprises.
68. How did Lee De Forest improve the existing telephone?
He integrated the mouthpiece and the receiver.
He modified a pipe to transmit sound.
He created a device to boost the reception quality.
He made implementation of the dial system possible.
69. The author of the passage implies that telephone networks expanded
because of ...
a series of breakthroughs.
the work of a few inventors.
multiple technical blunders. staunch public and private support.
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