TAT-1, the First Transatlantic Telephone System, Lantic Telephone Cable, TAT-1, Which Inaugurated the Modern Era of Which Had Been Inaugurated on the Previous Day
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History/Histoire Paths Beneath the Seas: Transatlantic Telephone Cable Systems 1.0 Inception of True Global Telecommunications by Jeremiah F. Hayes t is nearly 50 years since the September 26, 1956 edition of I the New York Times had the front page headline: Concordia University Abstract On the same day, similar stories appeared in newspapers throughout The year 2006 marks the fiftieth anniversary of the first transat- Canada. The subject was TAT-1, the first transatlantic telephone system, lantic telephone cable, TAT-1, which inaugurated the modern era of which had been inaugurated on the previous day. Simultaneously, a global communications. Over the last fifty years since TAT-1 went symposium on the Atlantic Cable was in progress at the Chateau Laurier into service, the capacity of telephone cables has grown explosive- in Ottawa. TAT-1 began the modern era of global communications. ly from the initial thirty-six voice-band channels to modern broad- Before TAT-1, voice was carried on unreliable and expensive radio chan- band optical fiber systems, which can carry 100 million voice cir- nels. Text messaging was carried on submarine telegraph cables (the cuits. As well as a beginning, TAT-1 was a continuation; submarine technology of the previous 90 years) which was reliable, but slow and telegraph cables had been in operation for 90 years. The paper expensive. reviews the history of submarine cable starting with the telegraph era, continuing through the TAT-1 and the coaxial systems that suc- ceeded it and culminating in the modern optical systems. The 2. Back to the Beginning prominent role played by Canada in all of these developments is As well as being a beginning, TAT-1 is the continuation of a story that highlighted. began on November 8, 1850 with a letter by the Catholic bishop of Newfoundland, J.T.M. Mullock in the St. John’s Courier . His Grace out- lined a scheme whereby messages dropped from ships passing the east- ern coast could be relayed by telegraph across Newfoundland and the Sommaire Cabot Strait to mainland North America, effecting a saving of days. L’année 2006 souligne le 50e anniversaire du premier câble télé- Fredrick Glisborne, an English telegraph engineer took up the challenge phonique transatlantique, TAT-1, qui a inauguré l’ère moderne des and began the construction of the telegraph line across the rugged inte- télécommunications globales. Depuis les 50 ans que TAT-1 a été rior of Newfoundland. Unfortunately, he ran out of money a short way mis en service, la capacité des câbles téléphoniques a crû de façon out from St. John’s. Before shuffling off the historical scene, Glisborne’s explosive depuis les 36 canaux initiaux à fréquence vocale made one lasting contribution: enlisting the involvement of a retired jusqu’aux systèmes modernes de fibres optiques à large bande, paper manufacturer, Cyrus Field. Field immediately went beyond the lesquels peuvent transporter 100 million de circuits vocaux. De relay scheme by advocating transatlantic telegraph transmission. His même qu’un commencement, TAT-1 a été une continuation : les first concerns were with, what he called, the twin problems of “geogra- câbles télégraphiques sous-marins étaient en opération depuis 90 phy and lightning”. On the latter, the challenge of long distance electri- ans. Cet article parcourt l’histoire du câble sous-marin depuis l’ère cal transmission, he consulted Samuel Morse, receiving assurances of télégraphique, en passant par TAT-1 et les systèmes coaxiaux qui feasibility. On the geography, he was encouraged by Lt M. F. Maury, l’ont succédé et culminant vers les systèmes optiques modernes. Head of the National Observatory in Washington. In 1853, the US Brig Le rôle substantiel joué par le Canada dans tous ces développe- Dolphin had surveyed the ocean floor on the likely path across the ments est souligné. Atlantic and found a ‘telegraph ridge’, whose depth and the surface were suitable for cable laying. The 1857 and 1858 Exped- ocean splice. William itions Thompson, later Lord Kelvin The first task was installing was the electrician on board, the cable across the monitoring electrical continu- Newfoundland (See Figure 1.) ity with his mirror gal- The route consisted of four vanometer. Unfortunately, hundred miles of wilderness after 200 miles the cable with mountains, rivers and broke and was lost in 2000 gorges – formidable obstacles. GULF OF fathoms. ST. LAWRENCE In 1856 a cable connecting The same cable was used in Cape Ray to Cape Breton in the 1858 attempt; it was, in Nova Scotia was laid. retrospect, an error. The same Gander Corner Brook two ships met in mid-ocean The project then turned, in the • summer of 1857, to the bridg- Bonavista with Niagara laying. to the ing of the Atlantic. The NEWFOUNDLAND • west and Agamemnon to the east. Based on the lessons American naval ship Niagara Submarine Cable 1855 TELEGRAPH started from Queenstown Heart's Content learned in 1857, the cable lay- • ing machinery had been (now called Cobh) followed Cape Ray • Bay Bulls St. John's • • by the British ship Port-aux-Basques improved. There were still Agamemnon, both fully cable breaks; nevertheless, the Submarine Cable Placentia loaded with cable. The plan ATLANTIC OCEAN lay finally succeeded. was for Niagara to start laying •Cape Race The new telegraph connec- from Valencia Harbour. tion to England was greeted Agamemnon would then fin- with a widespread outpour- ish the lay to Trinity Bay in Figure 1: The Route of the 1855 Telegraph Across Newfoundland ing of joy in the New World. Newfoundland after a mid- This spirit is exemplified in Figure 2 which shows a woodcut depicting huge bursts of fireworks over New York’s City Hall1. The cable never worked very well and 1 This as well as other wonderful illustrations are reproduced in [2]. failed after a month of shaky operation. 18 IEEE Canadian Review — Spring / Printemps 2006 The 1865 and 1866 Expeditions In 1919, a study of transoceanic submarine telephone cable was initiat- ed by American Telephone and Telegraph Company(AT&T). The Alarmed by a succession of costly failures in cable laying operations, the advances in materials, mentioned above, enhanced the feasibility of the British government convened a blue ribbon committee to examine the project. In 1928 this work culminated in a proposal for a repeaterless whole question and to make recommendation. There had been a few cable bearing a single voice channel across the Atlantic. Two considera- examples of success providing grounds for hope. The committee made a tions killed the project: radio circuits were continuously improving and number of recommendations one of which was a heavier and bulkier the cost estimate was $15,000,000, a substantial sum in the midst of the cable; accordingly, the demands on the cable laying ship were corre- spondingly greater. By a stroke of good fortune, just the right vessel was Great Depression. available-the Great Eastern, which was five or six times the size of any- By the early 1930’s electronic technology had advanced to the point thing else afloat when completed in 1857. where a submarine cable system with repeaters became feasible for the Armed with experience and new equipment, the 1865 lay went well until transatlantic link. The design of repeaters presented two challenges: there was a break 600 miles from Newfoundland. The position was care- electrical and mechanical. The electrical challenge was reliability; fully noted for future retrieval. Flaws were identified and rectified, and repeaters were expected to lie on the ocean bottom for twenty years. The the expedition in 1866 suc- cost associated with the ceeded. The cable was repair due to component brought ashore at Heart’s failure was prohibitive. All Content a deep, still inlet on of the electrical compo- Trinity Bay. There was a nents were subject to rigid message from Vancouver to reliability requirements; London on July 31, 1866. however, most fragile There was a double triumph were the vacuum tubes, as the Great Eastern grap- which were the only means pled for and found the end of amplification. Devel- of the 1865 cable. Thus, opment of these super reli- there were two fully opera- able tubes was initiated in tional cables! There has 1932. They were life tested been continuous operation for a period of eighteen ever since. years. When installed they Thereafter, submarine cable were significantly below telegraph service developed the current state of the art, continually. A noteworthy a mutual conductance of point was reached on 1000 vs. 6000 micro mhos. November 1, 1902 when the They were manufactured “All-Red Route” was inau- under conditions that pre- gurated. This was a globe saged those of modern encircling telegraph path semiconductor fabrication. linking only parts of the The repeater design fea- British Empire. On the west tures also contributed to coast the route was across reliability. In order to Vancouver island and Figure 2: Fireworks in N.Y. City, celebrating the Atlantic telegraph cable increase tube life, the sig- entered the ocean at Illustration reproduced with permission of Emphemera Society of America nal levels into each stage of Bamfield connecting to the amplifier were a level Fanning Island over the longest link in the system, 4000 nautical miles. lower than that causing grid current to flow. In parallel to the three stages of the amplifier was a gas tube which would fire and bypass the stages A significant improvement in cable performance was obtained by apply- in the event of a tube failure. In each repeater, was a crystal tuned to a ing the principle of inductive loading derived by Oliver Heaviside. In frequency unique to the repeater, thus allowing a malfunctioning 1924, permalloy, a Bell Labs invention, was wrapped around telegraph repeater to be identified.