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Quindar Tones
Quindar tones are the "beeps" that are heard during the American space missions. During the early days of the space program they were a means by which remote transmitters on Earth were turned on and off so that the capsule communicator (CapCom) could communicate with the crews of the spacecraft. It was a means of in-band signaling to simulate the action of the push-to-talk and release-to-listen (often referred to as PTT) button commonly found on two-way radio systems and walkie-talkies. However, even though the tones are no longer necessary with modern digital communication systems, they have been retained both for their historic aspect, and because flight controllers say they appreciate the audible cue of an imminent transmission. Rationale When Mission Control (in Houston, Texas) wanted to talk to astronauts, the capsule communicator (CapCom) pushed a button (push-to-talk, or PTT) that turned on the transmitter, then spoke, then released the button. When the transmitter is loca ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Capsule Communicator
Flight controllers are personnel who aid space flight by working in mission control centers such as NASA's Christopher C. Kraft Jr. Mission Control Center or ESA's European Space Operations Centre. Flight controllers work at computer consoles and use telemetry to monitor various technical aspects of a space mission in real-time. Each controller is an expert in a specific area and constantly communicates with additional experts in the "back room". The flight director, who leads the flight controllers, monitors the activities of a team of flight controllers, and has overall responsibility for success and safety. NASA's flight controllers The room where the flight controllers work was called the mission operations control room (MOCR, pronounced "moh-ker"), and now is called the flight control room (FCR, pronounced "ficker"). The controllers are experts in individual systems, and make recommendations to the flight director involving their areas of responsibility. Any control ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
YouTube
YouTube is an American social media and online video sharing platform owned by Google. YouTube was founded on February 14, 2005, by Steve Chen, Chad Hurley, and Jawed Karim who were three former employees of PayPal. Headquartered in San Bruno, California, it is the second-most-visited website in the world, after Google Search. In January 2024, YouTube had more than 2.7billion monthly active users, who collectively watched more than one billion hours of videos every day. , videos were being uploaded to the platform at a rate of more than 500 hours of content per minute, and , there were approximately 14.8billion videos in total. On November 13, 2006, YouTube was purchased by Google for $1.65 billion (equivalent to $ billion in ). Google expanded YouTube's business model of generating revenue from advertisements alone, to offering paid content such as movies and exclusive content produced by and for YouTube. It also offers YouTube Premium, a paid subs ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Johnson Space Center
The Lyndon B. Johnson Space Center (JSC) is NASA's center for human spaceflight in Houston, Texas (originally named the Manned Spacecraft Center), where human spaceflight training, research, and flight controller, flight control are conducted. It was renamed in honor of the late U.S. president and Texas native, Lyndon B. Johnson, by an act of the United States Senate on February 19, 1973. JSC consists of a complex of 100 buildings constructed on in Clear Lake (region), Clear Lake. The center is home to NASA Astronaut Corps, NASA's astronaut corps, and is responsible for training astronauts from both the U.S. and its international partners. It also houses the Christopher C. Kraft Jr. Mission Control Center, which has provided the flight controller, flight control function for every NASA human spaceflight since Gemini 4 (including Apollo program, Apollo, Skylab, Apollo–Soyuz, and Space Shuttle program, Space Shuttle). It is popularly known by its radio call signs "Mission Contr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Voice-operated Switch
In telecommunications, a voice operated switch, also known as VOX or voice-operated exchange, is a switch that operates when sound over a certain threshold is detected. It is usually used to turn on a transmitter or recorder when someone speaks and turn it off when they stop speaking. It is used instead of a push-to-talk button on transmitters or to save storage space on recording devices. On cell phones A mobile phone or cell phone is a portable telephone that allows users to make and receive Telephone call, calls over a radio frequency link while moving within a designated telephone service area, unlike fixed-location phones (landline phone ..., it is used to save battery life. Intercom systems that use a speaker in a room as both a speaker and a microphone will often use VOX on the main console to switch the audio direction during a conversation. The circuit usually includes a delay between the sound stopping and switching direction, to avoid the circuit turning off durin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Repeater
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 longer distances or be received on the other side of an obstruction. Some types of repeaters broadcast an identical signal, but alter its method of transmission, for example, on another frequency or baud rate. There are several different types of repeaters; a telephone repeater is an amplifier in a telephone line, an optical repeater is an optoelectronic circuit that amplifies the light beam in an optical fiber cable; and a radio repeater is a radio receiver and transmitter that retransmits a radio signal. A broadcast relay station is a repeater used in broadcast radio and television. Overview When an information-bearing signal passes through a communication channel, it is progressively degraded due to loss of power. For example, when a telephone call passes through a wire telephone line, some of the p ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Half-duplex
A duplex communication system is a point-to-point system composed of two or more connected parties or devices that can communicate with one another in both directions. Duplex systems are employed in many communications networks, either to allow for simultaneous communication in both directions between two connected parties or to provide a reverse path for the monitoring and remote adjustment of equipment in the field. There are two types of duplex communication systems: full-duplex (FDX) and half-duplex (HDX). In a full-duplex system, both parties can communicate with each other simultaneously. An example of a full-duplex device is plain old telephone service; the parties at both ends of a call can speak and be heard by the other party simultaneously. The earphone reproduces the speech of the remote party as the microphone transmits the speech of the local party. There is a two-way communication channel between them, or more strictly speaking, there are two communication channel ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Courtesy Tone
Courtesy (from the word , from the 12th century) is gentle politeness and courtly manners. In the Middle Ages in Europe, the behaviour expected of the nobility was compiled in courtesy books. History The apex of European courtly culture was reached in the Late Middle Ages and the Baroque period (i.e. roughly the four centuries spanning 1300–1700). The oldest courtesy books date to the 13th century, but they become an influential genre in the 16th, with the most influential of them being '' Il Cortegiano'' (1508), which not only covered basic etiquette and decorum but also provided models of sophisticated conversation and intellectual skill. The royal courts of Europe persisted well into the 18th century (and to some limited extent to the present day), but in the 18th century, the notion of ''courtesy'' was replaced by that of '' gallantry'', referring to an ideal emphasizing the display of affected sensitivity in direct contrast with the ideals of self-denial and dignified s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Astronauts
An astronaut (from the Ancient Greek (), meaning 'star', and (), meaning 'sailor') is a person trained, equipped, and deployed by a List of human spaceflight programs, human spaceflight program to serve as a commander or crew member of a spacecraft. Although generally reserved for professional space travelers, the term is sometimes applied to anyone who travels into space, including scientists, politicians, journalists, and space tourists. "Astronaut" technically applies to all human space travelers regardless of nationality. However, astronauts fielded by Russia or the Soviet Union are typically known instead as cosmonauts (from the Russian "kosmos" (космос), meaning "space", also borrowed from Greek ). Comparatively recent developments in crewed spaceflight made by China have led to the rise of the term taikonaut (from the Standard Chinese, Mandarin "tàikōng" (), meaning "space"), although its use is somewhat informal and its origin is unclear. In China, the People' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Earth
Earth is the third planet from the Sun and the only astronomical object known to Planetary habitability, harbor life. This is enabled by Earth being an ocean world, the only one in the Solar System sustaining liquid surface water. Almost all of Earth's water is contained in its global ocean, covering Water distribution on Earth, 70.8% of Earth's crust. The remaining 29.2% of Earth's crust is land, most of which is located in the form of continental landmasses within Earth's land hemisphere. Most of Earth's land is at least somewhat humid and covered by vegetation, while large Ice sheet, sheets of ice at Polar regions of Earth, Earth's polar polar desert, deserts retain more water than Earth's groundwater, lakes, rivers, and Water vapor#In Earth's atmosphere, atmospheric water combined. Earth's crust consists of slowly moving tectonic plates, which interact to produce mountain ranges, volcanoes, and earthquakes. Earth's outer core, Earth has a liquid outer core that generates a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Human Voice
The human voice consists of sound Voice production, made by a human being using the vocal tract, including Speech, talking, singing, Laughter, laughing, crying, screaming, shouting, humming or yelling. The human voice frequency is specifically a part of human sound production in which the vocal folds (vocal cords) are the primary sound source. (Other sound production mechanisms produced from the same general area of the body involve the production of Voicelessness, unvoiced consonants, Click consonant, clicks, whistling and whispering.) Generally speaking, the mechanism for generating the human voice can be subdivided into three parts; the lungs, the vocal folds within the larynx (voice box), and the articulators. The lungs, the "pump" must produce adequate airflow and air pressure to vibrate vocal folds. The vocal folds (vocal cords) then vibrate to use airflow from the lungs to create audible pulses that form the laryngeal sound source. The muscles of the larynx adjust the len ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Passband
A passband is the range of frequency, frequencies or wavelengths that can pass through a Filter (signal processing), filter. For example, a radio receiver contains a bandpass filter to select the frequency of the desired radio signal out of all the radio waves picked up by its antenna. The passband of a receiver is the range of frequencies it can receive when it is tuned into the desired frequency as in a radio station or television channel. A band-pass filter, bandpass-filtered signal (that is, a signal with energy only in a passband), is known as a bandpass signal, in contrast to a baseband signal. The bandpass filter usually has two stopband, band-stop filters. Filters In telecommunications, optics, and acoustics, a passband (a band-pass filtered signal) is the portion of the frequency spectrum that is transmitted (with minimum relative loss or maximum relative Gain (electronics), gain) by some filtering device. In other words, it is a ''band'' of frequencies which ''pa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
SpaceX Crew-1
SpaceX Crew-1 (was also known as USCV-1 or simply Crew-1) was the first operational crewed flight of a SpaceX Dragon 2, Crew Dragon spacecraft and the maiden flight of the Crew Dragon Resilience, Crew Dragon ''Resilience'' spacecraft. It was also the second crewed orbital flight launch by the United States since that of STS-135 in July 2011. ''Resilience'' launched on 16 November 2020 at 00:27:17 Coordinated Universal Time, UTC on a Falcon 9 from Kennedy Space Center Kennedy Space Center Launch Complex 39A, Launch Complex 39A (LC-39A), carrying NASA astronaut, astronauts Michael S. Hopkins, Michael Hopkins, Victor J. Glover, Victor Glover and Shannon Walker, along with JAXA astronaut Soichi Noguchi, all members of the Expedition 64 crew. The mission was the second overall crewed orbital flight of the Crew Dragon. Crew-1 was the first operational mission to the International Space Station (ISS) in the Commercial Crew Program. Originally designated "USCV-1" by NASA in 2012, the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
