In telecommunications, a repeater is an electronic device that receives a signal and retransmits it. Repeaters are used to extend transmissions so that the signal can cover distances or be received on the other side of an obstruction. Some types of repeaters broadcast a signal, but alter its method of transmission, for example. A broadcast relay station is a used in broadcast radio. When an information-bearing signal passes through a channel, it is progressively degraded due to loss of power. The longer the wire is, the power is lost. So with a long enough wire the call will not be audible at the other end, the farther from a radio station a receiver is, the weaker the radio signal, and the poorer the reception. A repeater is a device in a communication channel that increases the power of a signal and retransmits it. Since it amplifies the signal, it requires a source of electric power, the term repeater originated with telegraphy in the 19th century, and referred to an electromechanical device used to regenerate telegraph signals.
Use of the term has continued in telephony and data communications and this is used to increase the range of telephone signals in a telephone line. They are most frequently used in trunklines that carry long distance calls, since the telephone is a duplex communication system, the wire pair carries two audio signals, one going in each direction. So telephone repeaters have to be bilateral, amplifying the signal in both directions without causing feedback, which complicates their design considerably, telephone repeaters were the first type of repeater and were some of the first applications of amplification. The development of telephone repeaters between 1900 and 1915 made long distance phone service possible, however most telecommunications cables are now fiber optic cables which use optical repeaters. Submarine cable repeater This is a type of telephone used in underwater submarine telecommunications cables. This is used to increase the range of signals in a fiber optic cable, digital information travels through a fiber optic cable in the form of short pulses of light.
The light is made up of particles called photons, which can be absorbed or scattered in the fiber, optical amplifiers are being developed for repeaters to amplify the light itself without the need of converting it to an electric signal first. Some repeaters have been powered by light energy transmitted down the fiber with the signal and this is used to extend the range of coverage of a radio signal. A radio repeater usually consists of a receiver connected to a radio transmitter
STS-114 was the first Return to Flight Space Shuttle mission following the Space Shuttle Columbia disaster. Discovery launched at 10,39 EDT,26 July 2005, the mission ended on 9 August 2005 when Discovery landed at Edwards Air Force Base in California. Poor weather over the Kennedy Space Center in Florida hampered the shuttle from using its landing site. Analysis of the footage showed debris separating from the external tank during ascent. As a result, NASA decided on 27 July to postpone future shuttle flights pending additional modifications to the flight hardware, Shuttle flights resumed a year with STS-121 on 4 July 2006. This mission was to carry the Expedition 7 crew to the ISS, the original crew was to be, STS-114 marked the return to flight of the Space Shuttle after the Columbia disaster and was the second Shuttle flight with a female commander. The STS-114 mission was initially to be aboard the orbiter Atlantis. During OMM for Discovery, an actuator on the RSB system was found to be installed incorrectly and this created a fleet wide suspect condition.
Seventeen years prior, Discovery had flown NASAs previous Return to Flight mission, the STS-114 mission delivered supplies to the International Space Station. However, the focus of the mission was testing and evaluating new Space Shuttle flight safety techniques. The crewmembers used the new Orbiter Boom Sensor System – a set of instruments on a 50-foot extension attached to the Canadarm, the OBSS instrument package consists of visual imaging equipment and a Laser Dynamic Range Imager to detect problems with the shuttles Thermal Protection System. STS-114 was classified as Logistics Flight 1 and they deployed MISSE5 to the stations exterior, and replaced one of the ISSs Control Moment Gyroscopes. The CMG was carried up on the LMC at the rear of the payload bay, the crew conducted three spacewalks while at the station. The first demonstrated repair techniques on the Shuttles Thermal Protection System, during the second, the spacewalkers replaced the failed gyroscope. On the third, they installed the External Stowage Platform and repaired the shuttle, on 1 August, it was announced that protruding gap fillers on the front underside of the shuttle would be inspected and dealt with during the third spacewalk of the mission.
The spacewalk was conducted on the morning of 3 August, Robinson easily removed the two fillers with his fingers. Later on the day, NASA officials said that they were looking closely at a thermal blanket located next to the commanders window on the port side of the orbiter. Published reports on 4 August 2005 said that wind tunnel testing had demonstrated that the orbiter was safe to re-enter with the billowed blanket
NASA EDGE is a video podcast which explores different missions and projects developed by NASA. The program was released by NASA on March 18,2007, the show explores the contributions NASA has made to society as well as the progress of current projects in materials and space exploration. NASA EDGE vodcasts can be downloaded from the NASA website and from iTunes, as of February 2010, the average download rate is more than 420,000 per month, with over one million downloads in December 2009 and January 2010. NASA and the NASA EDGE have developed interactive programs designed to complement the vodcast, the Lunar Electric Rover App allows users to drive a simulated Lunar Electric Rover between objectives, and provides information about and images of the vehicle. The NASA EDGE Widget provides a user interface for accessing NASA EDGE vodcasts, image galleries. NASA TV NASAcast NASA360 NASA eClips NASA EDGE website NASA EDGE blog
NASA360 is a half-hour vodcast developed by NASA in partnership with the National Institute of Aerospace. The show premiered in August 2008 and it has aired on more than 450 TV stations across the country, is available on air and cruise lines, and is consistently one of the top-downloaded programs on the NASA. gov website. It is currently starting its fifth season, NASA360 is one of four programs in NASAs award-winning eClips suite of web-based shows designed to encourage careers in science, technology and mathematics. NASA360 is written and edited by Timothy J and these include lithium ion batteries, medical innovations, sporting equipment, and automotive and aircraft safety and efficiency, among many more. NASA360 is shot on-location at NASA centers across the country, NASA360 was originally created in 2006 by producers Kevin Krigsvold and Michael Bibbo. It was hosted by Johnny Alonso and Jennifer Pulley through 2012,23 episodes were produced during this period. It is available from numerous outlets, including Hulu.
com, iTunes, YouTube, Miro Guide, AOL Video, Red Orbit, NASA360 is available on Hulu. com. Hulu along with Hulu Plus has 29 million unique viewers every month, NASA360 is an active member of the social networking communities at Twitter and Facebook with more than 70,000 social media followers and fans. NASA 360s Backstage photo gallery averages about 5,000 views per week, NASA360 won a Capital Chesapeake Bay Emmy Award on June 15,2013 for the program, NASA360, Rocks & Rovers. The same episode, which highlights NASAs Sample Return Robot Centennial Challenge garnered two 2013 Telly awards in the Government and Instructional/Public Outreach categories, in June 2011, former Director/Editor Michael Bibbo was nominated in the single camera editing category for the National Daytime Emmy Awards. C. NASA360 has partnered with AMP International to air programs on airlines, singapore Airlines, US Air, and Philippines Airlines air NASA360 as an on-board entertainment option. As of May 2013, the program had been downloaded nearly 14 million times from the NASA portal, NASA360 website NASA360 at the Internet Movie Database
George Diller is a specialist in the NASA public affairs office at the Kennedy Space Center. Diller provided launch commentary from the launch of STS-27 through STS-135 the final launch of the program and he is known for his liftoff line he gave as the shuttle and other vehicles lifted off the pad. Diller is a native Floridian, having grown up in Sarasota and he graduated from the University of South Florida, Tampa campus first in 1972 and later in 1977. He has lived in Titusville since October 1978 and he worked for 11 years in radio broadcasting at stations in Clearwater and Orlando, and had among his responsibilities covering the Kennedy Space Center as a reporter. Jack King This article incorporates public domain material from websites or documents of the National Aeronautics, official website montage of George Diller space shuttle launch commentary
International Space Station
The International Space Station is a space station, or a habitable artificial satellite, in low Earth orbit. Its first component launched into orbit in 1998, and the ISS is now the largest man-made body in space, the ISS consists of pressurised modules, external trusses, solar arrays, and other components. ISS components have been launched by Russian Proton and Soyuz rockets, the ISS serves as a microgravity and space environment research laboratory in which crew members conduct experiments in biology, human biology, astronomy and other fields. The station is suited for the testing of systems and equipment required for missions to the Moon. The ISS maintains an orbit with an altitude of between 330 and 435 km by means of reboost manoeuvres using the engines of the Zvezda module or visiting spacecraft and it completes 15.54 orbits per day. The ISS is the space station to be inhabited by crews, following the Soviet and Russian Salyut, Almaz. The station has continuously occupied for 16 years and 156 days since the arrival of Expedition 1 on 2 November 2000.
This is the longest continuous presence in low Earth orbit. It has been visited by astronauts and space tourists from 17 different nations, Soyuz has very limited downmass capability. The ISS programme is a joint project among five participating space agencies, NASA, Roscosmos, JAXA, ESA, the ownership and use of the space station is established by intergovernmental treaties and agreements. The station is divided two sections, the Russian Orbital Segment and the United States Orbital Segment, which is shared by many nations. As of January 2014, the American portion of ISS is being funded until 2024, Roscosmos has endorsed the continued operation of ISS through 2024 but has proposed using elements of the Russian Orbital Segment to construct a new Russian space station called OPSEK. On 28 March 2015, Russian sources announced that Roscosmos and NASA had agreed to collaborate on the development of a replacement for the current ISS. NASA issued a statement expressing thanks for Russias interest in future co-operation in space exploration.
According to the original Memorandum of Understanding between NASA and Rosaviakosmos, the International Space Station was intended to be a laboratory and factory in low Earth orbit. It was planned to provide transportation and act as a base for possible future missions to the Moon, Mars. In the 2010 United States National Space Policy, the ISS was given roles of serving commercial, diplomatic. The ISS provides a platform to conduct scientific research, the ISS simplifies individual experiments by eliminating the need for separate rocket launches and research staff
DirecTV is an American direct broadcast satellite service provider based in El Segundo, California and is a subsidiary of AT&T. Its satellite service, launched on June 17,1994, transmits digital television and audio to households in the United States, Latin America. Its primary competitors are Dish Network and cable television providers, DirecTV provides television and audio services to subscribers through satellite transmissions. Services include the equivalent of local television stations, broadcast television networks, subscription television services, satellite radio services. Subscribers have access to hundreds of channels, so its competitors are cable television service, most subscribers use reception antennas which are much smaller than the first generation antennas, which were typically a few yards across. Advances in antenna technology, including fractal antennas, have allowed a reduction in antenna size across all industries. Receiving equipment includes a dish, an integrated receiver/decoder and a DirecTV access card.
Consumers who purchase DirecTV subscribe to various packages of DirecTV programming for which the subscriber pays a monthly fee, additional monthly fees may include a protection plan, DVR, additional receivers, HD channels, and other premium channel packages. A subscriber can order pay-per-view and video on demand events, all programming distributed by DirecTV is delivered to its broadcast centers in Castle Rock and Los Angeles, where it is digitized and compressed. The resulting signal is encrypted by DirecTV to prevent its unauthorized reception, DirecTV transmits these signals to several satellites located in geostationary orbit. As of the quarter ended September 30,2012, DirecTV U. S. had 19.981 million subscribers, for the same period, DirecTV Latin America ended with 9.666 million subscribers and revenues of US$1.577 billion. In addition to serving residences, DirecTV offers service to bars, hotels, the company offered mobile service for cars, and RVs as well as aircraft in cooperation with Connexion by Boeing.
On November 30,2016, DirecTV Now, an internet streaming TV service was launched, in 1953, Howard Hughes created the Howard Hughes Medical Institute, to which he transferred full ownership of Hughes Aircraft. Ostensibly created as a medical research foundation, HHMI was accused of being used by Hughes as a tax shelter. Following Hughes death in 1976, HHMI was incorporated in 1977, in 1984, the court appointed a new board for HHMI, which proceeded to sell off Hughes Aircraft to General Motors on December 20,1985, for an estimated $5.1 billion. General Motors merged Hughes Aircraft with its subsidiary Delco Electronics to create Hughes Electronics Corporation, the new subsidiary was initially composed of four units, Delco Electronics Company, Hughes Aircraft Company, Hughes Space and Communications Company, and Hughes Network Systems. Stanley E. Hubbard founded United States Satellite Broadcasting in 1981 and was a proponent for the development of direct-broadcast satellite service in the United States.
USSB was awarded five frequencies by the FCC, at the coveted 101 degree west satellite location, Hughes Communications, Inc. was awarded 27 frequencies at the same 101-degree location
Hot Bird is a group of satellites operated by Eutelsat, located at 13°E over the Equator and with a transmitting footprint over Europe, North Africa and the Middle East. Only digital radio and television channels are transmitted by the Hot Bird constellation, in addition there are a few interactive and IP services. The satellites currently operate at 13° East and are numbered 13B, 13C, Hot Bird 1 was launched by Ariane 44LP on 28 March 1995. The 13° East slot predates the launch, with Eutelsat 1F1 having been located there as early as 1983, Hot Bird 3 was launched by Ariane 44LP on 2 September 1997 and intended to be moved to 10°E to become Eurobird 10. During the drift from 13°E to 10°E, the satellite suffered loss of power from one solar array and it was nevertheless successfully moved to 10°E, but could only operate at a reduced capacity. Since then, it is operating at 4°E under the name Eurobird 4, at last it was moved to 75°E and renamed to ABS_1B. It has reached end-of-life. 5°E and renamed Eurobird 2, six transponders are leased to Arabsat under the name Badr 2, after having been called Arabsat 2D.
Hot Bird 6 was launched by Atlas V401 on 21 July 2002, starting on 12 June 2009, the day of Iranian elections, deliberate interference affecting this satellite was traced to Iran. Hot Bird 6 is the carrier for BBC Persian Television. As of 2013, it is replaced with Hot Bird 10 Hot Bird 7 was lost in December 2002 during the Ariane 5 ECA launch and its replacement, Hot Bird 7A was successfully launched on 11 March 2006. Hot Bird 8 was launched by Proton on 5 August 2006, with a launch mass of 4.9 tonnes, Hot Bird 8 is the largest and the most powerful broadcast satellite serving Europe. Hot Bird 9 was launched by Ariane 5 ECA in December 2008 and its entry into service enabled the Hot Bird 7A satellite to be redeployed to 9° East and rebranded Eurobird 9A, increasing capacity to 38 Ku band transponders at this orbital position. Hot Bird 10 was launched by Ariane 5 ECA in February 2009 with NSS-9, Spirale A, the Eutelat 33E satellite is located at 33° East, Eutelsat’s premium video neighbourhood for cable and satellite broadcasting in Europe, North Africa and the Middle East.
Bis TV Cyfrowy Polsat Eurosport Globecast NC+ NOVA Greece NOVA Cyprus Press TV Sky Italia Tivù Sat Viacom Up to 1000 television, official Eutelsat Satellites Eutelsat Hot Bird UnOfficial Hot Bird Frequency List Hot Bird 3D Channels
Canada is a country in the northern half of North America. Canadas border with the United States is the worlds longest binational land border, the majority of the country has a cold or severely cold winter climate, but southerly areas are warm in summer. Canada is sparsely populated, the majority of its territory being dominated by forest and tundra. It is highly urbanized with 82 per cent of the 35.15 million people concentrated in large and medium-sized cities, One third of the population lives in the three largest cities, Toronto and Vancouver. Its capital is Ottawa, and other urban areas include Calgary, Quebec City, Winnipeg. Various aboriginal peoples had inhabited what is now Canada for thousands of years prior to European colonization. Pursuant to the British North America Act, on July 1,1867, the colonies of Canada, New Brunswick and this began an accretion of provinces and territories to the mostly self-governing Dominion to the present ten provinces and three territories forming modern Canada.
With the Constitution Act 1982, Canada took over authority, removing the last remaining ties of legal dependence on the Parliament of the United Kingdom. Canada is a parliamentary democracy and a constitutional monarchy, with Queen Elizabeth II being the head of state. The country is officially bilingual at the federal level and it is one of the worlds most ethnically diverse and multicultural nations, the product of large-scale immigration from many other countries. Its advanced economy is the eleventh largest in the world, relying chiefly upon its abundant natural resources, Canadas long and complex relationship with the United States has had a significant impact on its economy and culture. Canada is a country and has the tenth highest nominal per capita income globally as well as the ninth highest ranking in the Human Development Index. It ranks among the highest in international measurements of government transparency, civil liberties, quality of life, economic freedom, Canada is an influential nation in the world, primarily due to its inclusive values, years of prosperity and stability, stable economy, and efficient military.
While a variety of theories have been postulated for the origins of Canada. In 1535, indigenous inhabitants of the present-day Quebec City region used the word to direct French explorer Jacques Cartier to the village of Stadacona, from the 16th to the early 18th century Canada referred to the part of New France that lay along the St. Lawrence River. In 1791, the area became two British colonies called Upper Canada and Lower Canada collectively named The Canadas, until their union as the British Province of Canada in 1841. Upon Confederation in 1867, Canada was adopted as the name for the new country at the London Conference. The transition away from the use of Dominion was formally reflected in 1982 with the passage of the Canada Act, that year, the name of national holiday was changed from Dominion Day to Canada Day
A direct-broadcast satellite is a type of artificial satellite which usually broadcasts satellite television signals for home reception. The type of satellite television which uses direct-broadcast satellites is known as direct-broadcast satellite television or direct-to-home television and these services were to use the D-Mac and D2-Mac format and BSS frequencies with circular polarization from orbital positions allocated to each country. Before these DBS satellites, home satellite television in Europe was limited to a few channels, really intended for cable distribution, in 1977, the ITU adopted an international BSS Plan under which each country was allocated specific frequencies at specific orbital locations for domestic service. Over the years, this plan has been modified to, for example, accommodate new countries, increase coverage areas, at present, numerous countries have brought into use their BSS Plan allocations. By contrast, the term DTH can apply to similar services transmitted over a range of frequencies transmitted from satellites that are not part of any internationally planned band.
The term DBS is often used interchangeably with DTH to cover both analog and digital video and audio services received by relatively small dishes, a DBS service usually refers to either a commercial service, or a group of free channels available from one orbital position targeting one country. In certain regions of the world, especially in North America, DBS is used to refer to providers of subscription satellite packages, the second commercial DBS service, Sky Television plc, was launched in 1989. Sky TV started as a four-channel free-to-air analogue service on the Astra 1A satellite, by 1991, Sky had changed to a conditional access pay model, and it launched a digital service, Sky Digital, in 1998, with analogue transmission ceasing in 2001. Since the DBS nomenclature is used in the UK or Ireland. News Corporation has a 32% stake in BSkyB, PrimeStar began transmitting an analog service to North America in 1991, and was joined by DirecTV, in 1994. At the time, DirecTVs introduction was the most successful consumer electronics debut in American history, although PrimeStar transitioned to a digital system in 1994, it was ultimately unable to compete with DirecTV, which required a smaller satellite dish and could deliver more programming.
DirecTV purchased PrimeStar in 1999 and moved all of that subscribers to DirecTV equipment. In 2008, Liberty Media Corporation purchased News Corporations controlling interest in DirecTV, in 1996, EchoStars Dish Network went online in the United States and, as DirecTVs primary competitor, achieved similar success. AlphaStar started but soon went under, astro was started, using a direct broadcast satellite system. Dominion Video Satellite Inc. s Sky Angel launched on a platform in the United States in 1996, with its DBS service geared toward the faith. It grew from six to 36 television and radio channels of entertainment, Christian-inspirational programming. Dominion, under its corporate name Video Satellite Systems Inc. Sky Angel, although a separate and independent DBS service, used the satellites, transmission facilities
Washington, D. C. formally the District of Columbia and commonly referred to as Washington, the District, or simply D. C. is the capital of the United States. The signing of the Residence Act on July 16,1790, Constitution provided for a federal district under the exclusive jurisdiction of the Congress and the District is therefore not a part of any state. The states of Maryland and Virginia each donated land to form the federal district, named in honor of President George Washington, the City of Washington was founded in 1791 to serve as the new national capital. In 1846, Congress returned the land ceded by Virginia, in 1871. Washington had an population of 681,170 as of July 2016. Commuters from the surrounding Maryland and Virginia suburbs raise the population to more than one million during the workweek. The Washington metropolitan area, of which the District is a part, has a population of over 6 million, the centers of all three branches of the federal government of the United States are in the District, including the Congress and Supreme Court.
Washington is home to national monuments and museums, which are primarily situated on or around the National Mall. The city hosts 176 foreign embassies as well as the headquarters of international organizations, trade unions, non-profit organizations, lobbying groups. A locally elected mayor and a 13‑member council have governed the District since 1973, the Congress maintains supreme authority over the city and may overturn local laws. D. C. residents elect a non-voting, at-large congressional delegate to the House of Representatives, the District receives three electoral votes in presidential elections as permitted by the Twenty-third Amendment to the United States Constitution, ratified in 1961. Various tribes of the Algonquian-speaking Piscataway people inhabited the lands around the Potomac River when Europeans first visited the area in the early 17th century, One group known as the Nacotchtank maintained settlements around the Anacostia River within the present-day District of Columbia.
Conflicts with European colonists and neighboring tribes forced the relocation of the Piscataway people, some of whom established a new settlement in 1699 near Point of Rocks, Maryland. 43, published January 23,1788, James Madison argued that the new government would need authority over a national capital to provide for its own maintenance. Five years earlier, a band of unpaid soldiers besieged Congress while its members were meeting in Philadelphia, known as the Pennsylvania Mutiny of 1783, the event emphasized the need for the national government not to rely on any state for its own security. However, the Constitution does not specify a location for the capital, on July 9,1790, Congress passed the Residence Act, which approved the creation of a national capital on the Potomac River. The exact location was to be selected by President George Washington, formed from land donated by the states of Maryland and Virginia, the initial shape of the federal district was a square measuring 10 miles on each side, totaling 100 square miles.
Two pre-existing settlements were included in the territory, the port of Georgetown, founded in 1751, many of the stones are still standing