the atlantic

Description

Telstar is the name of various communications satellites, including the first such satellite to relay television signals. The first two Telstar satellites were experimental and nearly identical. Telstar 1 was launched on top of a Thor-Delta rocket on July 10, 1962. It successfully relayed through space the first television pictures, telephone calls, fax images and provided the first live transatlantic television feed. Telstar 2 was launched May 7, 1963. Belonging to AT&T, the original Telstar was part of a multi-national agreement between AT&T, Bell Telephone Laboratories, NASA, the British General Post Office, and the French National PTT (Post, Telegraph & Telecom Office) to develop experimental satellite communications over the Atlantic Ocean. Bell Labs held a contract with NASA, reimbursing the agency three million pounds for each launch, independent of success. The US ground station was Andover Earth Station in Andover, Maine, built by Bell Labs. The main British ground station was at Goonhilly Downs in southwestern England, and it was used by the BBC. It was the international coordinator and the standards 525/405 conversion equipment (filling a large room) was researched and developed by the BBC and located in the BBC Television Centre, London. The French ground station was at Pleumeur-Bodou (48°47'10?N 3°31'26?W) in north-western France. The satellite was built by a team at Bell Telephone Laboratories, including John Robinson Pierce, who created the project;[1] Rudy Kompfner, who invented the traveling wave tube transponder used in the satellite;[1][2] and James M. Early, who designed its transistors and solar panels.[3] The satellite is roughly spherical, measures 34.5 inches (876.30 mm) in length, and weighs about 170 pounds (77 kg). Its dimensions were limited by what would fit on one of NASA's Delta rockets. Telstar was spin-stabilized, and its outer surface was covered with solar cells to generate electrical power. The power produced was a tiny 14 watts. The original Telstar had one innovative transponder to relay data, which was a television channel or multiplexed telephone circuits. An omnidirectional array of small antenna elements around the satellite's "equator" received 6 GHz microwave signals to be relayed. The transponder converted the frequency to 4 GHz, amplified the signals in a traveling-wave tube, and retransmitted them omnidirectionally via the adjacent array of larger box-shaped cavities. The prominent helical antenna was for telecommands from a ground station. More: http://en.wikipedia.org/wiki/Telstar