Broadcast relay station in the context of "Satellites"

A satellite or an artificial satellite is an object, typically a spacecraft, placed into orbit around a celestial body. They have a variety of uses, including communication relay, weather forecasting, navigation (GPS), broadcasting, scientific research, and Earth observation. Additional military uses are reconnaissance, early warning, signals intelligence and, potentially, weapon delivery. Other satellites include the final rocket stages that place satellites in orbit and formerly useful satellites that later become defunct.

Except for passive satellites, most satellites have an electricity generation system for equipment on board, such as solar panels or radioisotope thermoelectric generators (RTGs). Most satellites also have a method of communication to ground stations, called transponders. Many satellites use a standardized bus to save cost and work, the most popular of which are small CubeSats. Similar satellites can work together as groups, forming constellations. Because of the high launch cost to space, most satellites are designed to be as lightweight and robust as possible. Most communication satellites are radio relay stations in orbit and carry dozens of transponders, each with a bandwidth of tens of megahertz.

Stratovision was an airborne television transmission relay system using aircraft flying at high altitudes. In 1945, the Glenn L. Martin Company and Westinghouse Electric Corporation originally proposed television coverage of small towns and rural areas, as well as the large metropolitan centers, by 14 aircraft that would provide coverage for approximately 78% of the people in the United States. Although this was never implemented, the system has been used for domestic broadcasting in the United States, and by the U.S. military in South Vietnam and other countries.

Mount Qasioun (Arabic: جَبَل قَاسِيُون, romanized: Jabal Qāsiyūn) is a mountain overlooking the city of Damascus, Syria. It has a range of restaurants, from which the whole city can be viewed. Due to its high elevation, several communications and broadcasting networks constructed relay stations at the summit for the city's communications. As the city has expanded over the years, some districts have been established at the foot of the mountain. Its highest point is 1,151 metres (3,776 ft).

The following is a list of full-power non-commercial educational radio stations in the United States broadcasting programming from National Public Radio (NPR), which can be sorted by their call signs, frequencies, band, city of license and state. HD Radio subchannels and low-power translators are not included.