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Signal Strength And Readability Report
A signal strength and readability report is a standardized format for reporting the strength of the radio signal and the readability (quality) of the radiotelephone (voice) or radiotelegraph (Morse code) signal transmitted by another station as received at the reporting station's location and by their radio station equipment. These report formats are usually designed for only one communications mode or the other, although a few are used for both telegraph and voice communications. All but one of these signal report formats involve the transmission of numbers. History As the earliest radio communication used Morse code, all radio signal reporting formats until about the 1920s were for radiotelegraph, and the early voice radio signal report formats were based on the telegraph report formats. Timeline of signal report formats * The first signal report format code may have been QJS. * The U.S. Navy used R and K signals starting in 1929. * The QSK code was one of the twelve Q Code ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Radiotelephone
A radiotelephone (or radiophone), abbreviated RT, is a radio communication system for conducting a conversation; radiotelephony means telephony by radio. It is in contrast to ''radiotelegraphy'', which is radio transmission of telegrams (messages), or ''television'', transmission of moving pictures and sound. The term is related to radio broadcasting, which transmit audio one way to listeners. Radiotelephony refers specifically to two-way radio systems for bidirectional person-to-person voice communication between separated users, such as CB radio or marine radio. In spite of the name, radiotelephony systems are not necessarily connected to or have anything to do with the telephone network, and in some radio services, including GMRS, interconnection is prohibited. Design Mode of emission The word ''phone'' has a long precedent beginning with early US wired voice systems. The term means ''voice'' as opposed to telegraph or Morse code. This would include systems fitting i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
The Blackboard Jungle
''Blackboard Jungle'' is a 1955 American social drama film about an English teacher in an interracial inner-city school, based on the 1954 novel ''The Blackboard Jungle'' by Evan Hunter and adapted for the screen and directed by Richard Brooks. It is remembered for its innovative use of rock and roll in its soundtrack, for casting grown adults as high school teens, and for the unique breakout role of a black cast member, film icon Sidney Poitier, as a rebellious yet musically talented student. In 2016, ''Blackboard Jungle'' was selected for preservation in the United States National Film Registry by the Library of Congress as being "culturally, historically, or aesthetically significant". Factual background Hunter's novel was based on his early job as a teacher at Bronx Vocational High School, now known as Alfred E. Smith Career and Technical Education High School in the South Bronx. Hunter, then known as Salvatore Lombino, took the teaching job in 1950 after graduating from H ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Operating Signals
Operating signals are a type of brevity code used in operational communication among radio and telegraph operators. For example: * Prosigns for Morse code * 92 Code: telegraph brevity codes * Q code: initially developed for commercial radiotelegraph communication and adopted by other radio services * QN Signals: published by the ARRL and used in Amateur radio * R code and S Code: published by the British Post Office for coastal wireless stations and ships * X code: used by European military services in wireless telegraphy * Z code: used in early radiotelegraph communication See also * Brevity code * SINPO code - code used to describe the quality of radio transmissions, especially in reception reports written by shortwave listeners * R-S-T system- information about the quality of a radio signal being received. Used by amateur radio operators, shortwave listeners. * Morse code abbreviations * Telegraphese Telegram style, telegraph style, telegraphic style, or telegraphese is ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
English Phrases
English usually refers to: * English language * English people English may also refer to: Peoples, culture, and language * ''English'', an adjective for something of, from, or related to England ** English national identity, an identity and common culture ** English language in England, a variant of the English language spoken in England * English languages (other) * English studies, the study of English language and literature * ''English'', an Amish term for non-Amish, regardless of ethnicity Individuals * English (surname), a list of notable people with the surname ''English'' * People with the given name ** English McConnell (1882–1928), Irish footballer ** English Fisher (1928–2011), American boxing coach ** English Gardner (b. 1992), American track and field sprinter Places United States * English, Indiana, a town * English, Kentucky, an unincorporated community * English, Brazoria County, Texas, an unincorporated communit ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Procedure Word
Procedure words (abbreviated to prowords) are words or phrases limited to radio telephone procedure used to facilitate communication by conveying information in a condensed standard verbal format. Prowords are voice versions of the much older procedural signs for Morse code which were first developed in the 1860s for Morse telegraphy, and their meaning is identical. The NATO communications manual ACP-125 contains the most formal and perhaps earliest modern (post-World War II) glossary of prowords, but its definitions have been adopted by many other organizations, including the United Nations Development Programme, the U.S. Coast Guard, US Civil Air Patrol, US Military Auxiliary Radio System, and others. Prowords are one of several structured parts of radio voice procedures, including brevity codes and plain language radio checks. Examples According to the U.S. Marine Corps training document FMSO 108, "understanding the following PROWORDS and their respective definitions ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Perceptual Objective Listening Quality Analysis
Perceptual Objective Listening Quality Analysis (POLQA) was the working title of an ITU-T standard that covers a model to predict speech quality by means of analyzing digital speech signals. The model was standardized as Recommendation ITU-T P.863 (Perceptual objective listening quality assessment) in 2011. The second edition of the standard appeared in 2014, and the third, currently in-force edition was adopted in 2018 under the title Perceptual objective listening quality prediction. Measurement scope POLQA covers a model to predict speech quality,http://www.aes.org/e-lib/browse.cfm?elib=16829 Perceptual Objective Listening Quality Assessment (POLQA), The Third Generation ITU-T Standard for End-to-End Speech Quality Measurement Part I—Temporal Alignmenthttp://www.aes.org/e-lib/browse.cfm?elib=16830 Perceptual Objective Listening Quality Assessment (POLQA), The Third Generation ITU-T Standard for End-to-End Speech Quality Measurement Part II—Perceptual Model by means of digit ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Perceptual Evaluation Of Speech Quality
Perception () is the organization, identification, and interpretation of sensory information in order to represent and understand the presented information or environment. All perception involves signals that go through the nervous system, which in turn result from physical or chemical stimulation of the sensory system.Goldstein (2009) pp. 5–7 Vision involves light striking the retina of the eye; smell is mediated by odor molecules; and hearing involves pressure waves. Perception is not only the passive receipt of these signals, but it is also shaped by the recipient's learning, memory, expectation, and attention. Gregory, Richard. "Perception" in Gregory, Zangwill (1987) pp. 598–601. Sensory input is a process that transforms this low-level information to higher-level information (e.g., extracts shapes for object recognition). The process that follows connects a person's concepts and expectations (or knowledge), restorative and selective mechanisms (such as ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mean Opinion Score
Mean opinion score (MOS) is a measure used in the domain of Quality of Experience and telecommunications engineering, representing overall quality of a stimulus or system. It is the arithmetic mean over all individual "values on a predefined scale that a subject assigns to his opinion of the performance of a system quality". Such ratings are usually gathered in a subjective quality evaluation test, but they can also be algorithmically estimated. MOS is a commonly used measure for video, audio, and audiovisual quality evaluation, but not restricted to those modalities. ITU-T has defined several ways of referring to a MOS in RecommendatioITU-T P.800.1 depending on whether the score was obtained from audiovisual, conversational, listening, talking, or video quality tests. Rating scales and mathematical definition The MOS is expressed as a single rational number, typically in the range 1–5, where 1 is lowest perceived quality, and 5 is the highest perceived quality. Other MOS ranges ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Circuit Merit
The Circuit Merit system is a measurement process designed to assess the voice-to-noise ratio in wired and wireless telephone circuits, especially the AMPS system, and although its reporting scale is sometimes used as input for calculating mean opinion score, the rating system is officially defined relative to given ranges of voice-to-noise ratios. Various technical sources state that experimental research vary in what ratio is required for good understanding, but is typically above 20 dB, and noticeably higher reports of voice quality can be achieved when the ratio is near 30 dB. There are 5 levels of quality, detailed as follows: Measurement of audio speech-to-noise ratios in a way which reflects interfering effects in a meaningful manner is difficult for the kinds of noise often encountered at mobile system receivers. For this reason and as a matter of convenience, a subjective rating of the interfering effect of the noise using the term “circuit merit” is comm ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gemini IV
Gemini 4 (officially Gemini IV) With Gemini IV, NASA changed to Roman numerals for Gemini mission designations. was the second crewed spaceflight in NASA's Project Gemini, occurring in June 1965. It was the tenth crewed American spaceflight (including two X-15 flights at altitudes exceeding ). Astronauts James McDivitt and Ed White circled the Earth 66 times in four days, making it the first US flight to approach the five-day flight of the Soviet Vostok 5. The highlight of the mission was the first space walk by an American, during which White floated free outside the spacecraft, tethered to it, for approximately 23 minutes. The flight also included the first attempt to make a space rendezvous as McDivitt attempted to maneuver his craft close to the Titan II upper stage which launched it into orbit, but this was not successful. The flight was the first American flight to perform many scientific experiments in space, including use of a sextant to investigate the use of celes ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cliff Effect
In telecommunications, the (digital) cliff effect or brickwall effect is a sudden loss of digital signal reception. Unlike analog signals, which gradually fade when signal strength decreases or electromagnetic interference or multipath increases, a digital signal provides data which is either perfect or non-existent at the receiving end. It is named for a graph of reception quality versus signal quality, where the digital signal "falls off a cliff" instead of having a gradual rolloff. This is an example of an EXIT chart. The phenomenon is primarily seen in broadcasting, where signal strength is liable to vary, rather than in recorded media, which generally have a good signal. However, it may be seen in significantly damaged media, which is at the edge of readability. The term is also used in economics for an unrelated phenomenon. Broadcasting Digital television This effect can most easily be seen on digital television, including both satellite TV and over-the-air terrestri ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Wireless Telegraphy
Wireless telegraphy or radiotelegraphy is transmission of text messages by radio waves, analogous to electrical telegraphy using cables. Before about 1910, the term ''wireless telegraphy'' was also used for other experimental technologies for transmitting telegraph signals without wires. In radiotelegraphy, information is transmitted by pulses of radio waves of two different lengths called "dots" and "dashes", which spell out text messages, usually in Morse code. In a manual system, the sending operator taps on a switch called a telegraph key which turns the transmitter on and off, producing the pulses of radio waves. At the receiver the pulses are audible in the receiver's speaker as beeps, which are translated back to text by an operator who knows Morse code. Radiotelegraphy was the first means of radio communication. The first practical radio transmitters and receivers invented in 1894–1895 by Guglielmo Marconi used radiotelegraphy. It continued to be the only type ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
