Transatlantic telephone cable

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Radio link from 1927

A transatlantic telephone cable (TAT) or transatlantic cable is an underwater cable for telephone and data traffic, which at the bottom of the Atlantic Ocean is laid. Before the first transatlantic telephone cable TAT-1 went into operation in 1956, the transatlantic telephone service that had existed since 1927 was based on long-wave radio; this service cost nine pounds sterling for every three minutes or part thereof. The last 2000 telephone calls were made per year in this way. Before that, there had only been a permanent transatlantic connection for telegraphy only since 1866.

telegraphy

Historical distribution table

The first attempt to lay a cable between Britain and America was made in 1857 and 1858. It was possible to fall back on good experiences with coastal cables; However, the cable laid across the Atlantic became unusable after a few weeks of operation because Wildman Whitehouse used excessively high voltages during operation. It is believed that the cable would not have had a long life due to insulation problems inherent in the manufacture and handling of the cable.

Ten years later, however, better insulated cables were available that achieved a much longer service life. So-called coiled lines in the form of submarine cables were used. In 1865 a new transatlantic line was laid by the steamship Great Eastern ; but the cable tore 600 miles off the coast of Newfoundland and could not be recovered. Another cable was laid through the Great Eastern between July 13 and 27, 1866 and put into operation on July 28, 1866. The section of cable laid in 1865 could also be recovered later and the missing piece added. The Faraday laid in 1874 for the Siemens -Brüder Wilhelm and Werner von Siemens , the first transatlantic telegraph cable that was functional to the 1931st

In 1900 Germany not only had lines in the North and Baltic Seas with a total length of 4180 kilometers, but also a transatlantic cable that had been manufactured in England for the German-Atlantic Cable Company and from Emden ( East Frisia ) across the Azores island Faial to Coney Island in New York . In 1919 the number of operational transatlantic cables had grown to 13, mostly British owned.

Telephony and data traffic

The 3600 km long TAT-1 was born on 25 September 1956 between Oban ( Scotland ) and Clarenville ( Newfoundland taken) into operation. The connection had 36 telephone channels, one wire for each direction of speech, as well as 51 amplifiers, which were attached to the cable at a distance of 70 kilometers.

In the first 24 hours of operation, 588 calls were transferred between London and the USA and 119 from London to Canada . The capacity of the cable was therefore soon expanded to 48 channels. TAT-1 was finally shut down in 1978.

The second transatlantic telephone cable, TAT-2 , went into service on September 22, 1959; the number of voice channels is thereby by the method of time-assigned speech interpolation (time-assigned speech interpolation, TASI) increased to 87; With this method, a subscriber is only assigned a channel if he is actually speaking. From 1963, a semi-automatic telephone service between the Federal Republic of Germany and the USA could be offered via TAT-2 .

The TAT-3 , built with coaxial cables , was laid between 1963 and 1965; it stretched from Great Britain to New Jersey and had a capacity of 138 voice channels with a maximum of 276 voice connections and a repeater distance of 37 kilometers.

TAT-4 was relocated between France and New Jersey in 1965 with a capacity of 345 voice calls; two speaking groups served to connect Austria with the USA. From 1968 Austrians could also reach Canada via CANTAT.

The 6300 km long TAT-6 followed in 1976 between France and the USA; it had 4200 speech circuits and required 693 repeaters at a distance of 9 kilometers.

Overview, in chronological order

Cable name In operation Type Initial number of channels Last number of channels First end Second ending
TAT-1 1956-1988 galvanic 36 48 Scotland Newfoundland
TAT-2 1959-1982 galvanic 48 72 France Newfoundland
CANTAT -1 1961-1986 galvanic 80 - Newfoundland Scotland
TAT-3 1963-1986 galvanic 138 276 England New Jersey
TAT-4 1965-1987 galvanic 138 345 France New Jersey
PENCAN 1 1965 galvanic 160 - Spain Canary Islands
TAT-5 1970-1993 galvanic 845 2112 Rhode Island Spain
BRACAN I 1973-1996 galvanic 160 - Gran Canaria Brazil
CANTAT -2 1974-1992 galvanic 1,840 - Nova Scotia England
TAT-6 1976-1994 galvanic 4,000 10,000 Rhode Island France
TAT-7 1978-1994 galvanic 4,000 10,500 New Jersey England
TAT-8 1988-2002 glass fiber 40,000 - United States France
PTAT-1 1989 glass fiber 3 × 140 Mbit / s Bermuda Islands Ireland / England
TAT-9 1992-2003 glass fiber 80,000 - United States Spain
TAT-10 1992-2003 glass fiber 2 × 565 Mbit / s - United States North , Germany
TAT-11 1993-2003 glass fiber 2 × 565 Mbit / s - United States France
CANTAT -3 since 1994 glass fiber 2 × 2.5 Gbit / s Canada Germany
TAT-12/13 since 1996 glass fiber 2 × 5 Gbit / s - United States England / France
TAT-14 since 2001 glass fiber 64 × 10 Gbit / s - United States North , Germany

Cables with TAT in their name all run through the North Atlantic, and there are also some cables on routes further south, e.g. B. SAT-2 , ATLANTIS-2 and COLUMBUS-III .

All TAT cables are joint ventures between the American AT&T and a European telephone company, e.g. B. BT . CANTAT are Canadian transatlantic cables. A competitor during the 1990s was Global Crossing , which is now being liquidated .

The similar submarine connection to Asia is called SEA-ME-WE 3 .

literature

  • Friedrich Althaus: The new electric world band . In: The Gazebo . Issue 40, 1866 ( full text [ Wikisource ] - illustrated).
  • Heinrich Schellen: The Atlantic cable, its fabrication, its laying and its way of speaking . Braunschweig 1867. VIII, 168 S .: Ill. (Also published in three continuations in Westermann's yearbook of the Illustrierte Deutsche Monatshefte 1867).
  • John Griesemer: Intoxication . Novel. marebuchverlag, ISBN 3-936384-86-X .
    The novel describes the disastrous launch of the ship, the subsequent catastrophes and later the laying of the first telegraph cable between Europe and America through the Atlantic using this ship.
  • H. Philip Spratt: Transatlantic Paddle Steamers. 1967.

Web links

Individual evidence

  1. ^ History of the Transatlantic Cable - Dr. EOW Whitehouse and the 1858 trans-Atlantic cable
  2. ^ Milestones: Landing of the Transatlantic Cable, 1866 , IEEE Global History Network
  3. ↑ Europe calls America - the transatlantic cable connects two continents. Siemens Historical Institute, accessed June 14, 2019 .
  4. ↑ Cable Timeline: 1951-2000. Retrieved August 6, 2013 .
  5. ↑ 1973 BRACAN-1 (Brazil-Canary Islands) Cable. Retrieved August 6, 2013 .