transatlantic telephone
   HOME

TheInfoList



OR:

A transatlantic telecommunications cable is a
submarine communications cable A submarine communications cable is a cable laid on the seabed, sea bed between land-based stations to carry telecommunication signals across stretches of ocean and sea. The first submarine communications cables laid beginning in the 1850s car ...
connecting one side of the
Atlantic Ocean The Atlantic Ocean is the second-largest of the world's five oceans, with an area of about . It covers approximately 20% of Earth's surface and about 29% of its water surface area. It is known to separate the " Old World" of Africa ...
to the other. In the 19th and early 20th centuries, each cable was a single wire. After mid-century,
coaxial cable Coaxial cable, or coax (pronounced ) is a type of electrical cable consisting of an inner Electrical conductor, conductor surrounded by a concentric conducting Electromagnetic shielding, shield, with the two separated by a dielectric (Insulato ...
came into use, with amplifiers. Late in the 20th century, all cables installed used
optical fiber An optical fiber, or optical fibre in Commonwealth English, is a flexible, transparency and translucency, transparent fiber made by Drawing (manufacturing), drawing glass (silica) or plastic to a diameter slightly thicker than that of a Hair ...
as well as
optical amplifier An optical amplifier is a device that amplifies an optical signal (information theory), signal directly, without the need to first convert it to an electrical signal. An optical amplifier may be thought of as a laser without an optical cavity, ...
s, because distances range thousands of kilometers.


History

When the first
transatlantic telegraph cable Transatlantic telegraph cables were Submarine communications cable, undersea cables running under the Atlantic Ocean for telegraph communications. Telegraphy is now an obsolete form of communication, and the cables have long since been decommis ...
was laid in 1858 by
Cyrus West Field Cyrus West Field (November 30, 1819July 12, 1892) was an American businessman and financier who, along with other entrepreneurs, created the Atlantic Telegraph Company and laid the first Transatlantic telegraph cable, telegraph cable across the A ...
, it operated for only three weeks; subsequent attempts in 1865 and 1866 were more successful. In July 1866 '' Great Eastern'' sailed out of
Valentia Island Valentia Island () is one of Ireland Ireland ( ; ga, Éire ; Ulster Scots dialect, Ulster-Scots: ) is an island in the Atlantic Ocean, North Atlantic Ocean, in Northwestern Europe, north-western Europe. It is separated from Great Brit ...
,
Ireland Ireland ( ; ga, Éire ; Ulster Scots dialect, Ulster-Scots: ) is an island in the Atlantic Ocean, North Atlantic Ocean, in Northwestern Europe, north-western Europe. It is separated from Great Britain to its east by the North Channel (Grea ...
and on July 26th landed at Hearts Content in
Newfoundland Newfoundland and Labrador (; french: Terre-Neuve-et-Labrador; frequently abbreviated as NL) is the easternmost provinces and territories of Canada, province of Canada, in the country's Atlantic Canada, Atlantic region. The province comprises t ...
. It was active until 1965. Although a telephone cable was discussed starting in the 1920s, to be practical it needed a number of technological advances which did not arrive until the 1940s. Starting in 1927, transatlantic telephone service was radio-based. TAT-1 (Transatlantic No. 1) was the first transatlantic telephone cable system. It was laid between Gallanach Bay, near
Oban Oban ( ; ' in Scottish Gaelic meaning ''The Little Bay'') is a resort town within the Argyll and Bute council area of Scotland. Despite its small size, it is the largest town between Helensburgh and Fort William, Highland, Fort William. During ...
, and
Clarenville Clarenville is a town on the east coast of Newfoundland Newfoundland and Labrador (; french: Terre-Neuve-et-Labrador; frequently abbreviated as NL) is the easternmost provinces and territories of Canada, province of Canada, in the country ...
,
Newfoundland Newfoundland and Labrador (; french: Terre-Neuve-et-Labrador; frequently abbreviated as NL) is the easternmost provinces and territories of Canada, province of Canada, in the country's Atlantic Canada, Atlantic region. The province comprises t ...
between 1955 and 1956 by the
cable ship A cable layer or cable ship is a deep-sea vessel designed and used to lay underwater cables for telecommunications Telecommunication is the transmission of information by various types of technologies over wire, radio Radio is th ...
''
Monarch A monarch is a head of stateWebster's II New College DictionarMonarch Houghton Mifflin. Boston. 2001. p. 707. Life tenure, for life or until abdication, and therefore the head of state of a monarchy. A monarch may exercise the highest authority ...
''. It was inaugurated on September 25, 1956, initially carrying 36 telephone channels. In the first 24 hours of public service, there were 588 London–U.S. calls and 119 from London to Canada. The capacity of the cable was soon increased to 48 channels. Later, an additional three channels were added by use of C Carrier equipment. Time-assignment speech interpolation (TASI) was implemented on the TAT-1 cable in June 1960 and effectively increased the cable's capacity from 37 (out of 51 available channels) to 72 speech circuits. TAT-1 was finally retired in 1978. Later coaxial cables, installed through the 1970s, used
transistor file:MOSFET Structure.png, upright=1.4, Metal-oxide-semiconductor field-effect transistor (MOSFET), showing Metal gate, gate (G), body (B), source (S) and drain (D) terminals. The gate is separated from the body by an insulating layer (pink). A ...
s and had higher bandwidth. The
Moscow–Washington hotline The Moscow–Washington hotline (formally known in the United States as the Washington–Moscow Direct Communications Link; rus, Горячая линия Вашингтон — Москва, r=Goryachaya liniya Vashington–Moskva) is a system t ...
was initially connected through this system.


Current technology

All cables presently in service use
fiber optic An optical fiber, or optical fibre in Commonwealth English, is a flexible, transparency and translucency, transparent fiber made by Drawing (manufacturing), drawing glass (silica) or plastic to a diameter slightly thicker than that of a Hair ...
technology. Many cables terminate in Newfoundland and Ireland, which lie on the
great circle route Great-circle navigation or orthodromic navigation (related to orthodromic course; from the Greek Greek may refer to: Greece Anything of, from, or related to Greece, a country in Southern Europe: *Greeks, an ethnic group. *Greek language, a br ...
from
London London is the capital and List of urban areas in the United Kingdom, largest city of England and the United Kingdom, with a population of just under 9 million. It stands on the River Thames in south-east England at the head of a estuary dow ...
, UK to
New York City New York, often called New York City or NYC, is the List of United States cities by population, most populous city in the United States. With a 2020 population of 8,804,190 distributed over , New York City is also the L ...
, US. There has been a succession of newer transatlantic cable systems. All recent systems have used
fiber optic An optical fiber, or optical fibre in Commonwealth English, is a flexible, transparency and translucency, transparent fiber made by Drawing (manufacturing), drawing glass (silica) or plastic to a diameter slightly thicker than that of a Hair ...
transmission, and a self-healing ring topology. Late in the 20th century,
communications satellite A communications satellite is an artificial satellite that relays and amplifies radio Radio is the technology of signaling and telecommunication, communicating using radio waves. Radio waves are electromagnetic waves of frequency between ...
s lost most of their North Atlantic telephone traffic to these low-cost, high-capacity, low- latency cables. This advantage only increases over time, as tighter cables provide higher bandwidth – the 2012 generation of cables drop the transatlantic latency to under 60 milliseconds, according to Hibernia Atlantic, deploying such a cable that year. Some new cables are being announced on the South Atlantic: SACS (South Atlantic Cable System) and SAex (South Atlantic Express).


TAT cable routes

The TAT series of cables constitute a large percentage of all North Atlantic cables. All TAT cables are joint ventures between a number of
telecommunications Telecommunication is the transmission of information by various types of technologies over wire, radio Radio is the technology of signaling and telecommunication, communicating using radio waves. Radio waves are electromagnetic waves of ...
companies, e.g.
British Telecom BT Group plc ( trading as BT and formerly British Telecom) is a British multinational telecommunications holding company headquartered in London London is the capital and List of urban areas in the United Kingdom, largest city of Engl ...
. CANTAT cables terminate in Canada rather than in the US.


Private cable routes

There are a number of private non-TAT cables.


South Atlantic cable routes


See also

*
Cable layer A cable layer or cable ship is a deep-sea ship, vessel designed and used to lay underwater cables for Submarine communications cable, telecommunications, Submarine power cable, electric power transmission, military, or other purposes. Cable ship ...
*
List of international submarine communications cables This is a list of international submarine communications cables. It does not include List of domestic submarine communications cables, domestic cable systems, such as those on the coastlines of Japan, Italy, and Brazil. All the cable systems list ...


References


External links

*
Aronsson's Telecom History TimelineSubmarine Cable Landings Worldwide
{{DEFAULTSORT:Transatlantic Telephone Cable History of the telephone History of telecommunications in the United States History of telecommunications in the United Kingdom