TAT-3 was AT&T Corporation's third transatlantic telephone cable. It was in operation from 1963 to 1986. It had 414 kHz of bandwidth, allowing it to carry 138 telephone circuits (simultaneous calls). It was 3,518 nautical miles long, connecting Widemouth Bay in Cornwall, England to Tuckerton, New Jersey in the United States.
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TAT-3 Wikipedia(Text) CC BY-SA