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Reception Report
A reception report is a means by which radio stations (usually short- and medium-wave broadcasters) receive detailed feedback from their listeners about the quality and content of their broadcasts. A reception report consists of several pieces of information which help the station verify that the report confirms coverage of their transmission, and usually include the following information: *Date, time and frequency (in kHz) of the transmission *Station name *Description of the interval signal, if heard *Programme details *Name of announcers or programme host, if heard *Details of the overall signal quality (normally using the SINPO code) The listener's location relative to the station is also useful; this indicates how well the station's transmitter is performing and in which direction(s) its antenna is beaming the signal. The station also evaluates a reception report in light of the listener's receiver and antenna. Upon receipt of a correct report, a broadcaster sometimes issue ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Shortwave
Shortwave radio is radio transmission using radio frequencies in the shortwave bands (SW). There is no official definition of the band range, but it always includes all of the high frequency band (HF), which extends from 3 to 30 MHz (approximately 100 to 10 metres in wavelength). It lies between the medium frequency band (MF) and the bottom of the VHF band. Radio waves in the shortwave band can be reflected or refracted from a layer of electrically charged atoms in the atmosphere called the ionosphere. Therefore, short waves directed at an angle into the sky can be reflected back to Earth at great distances, beyond the horizon. This is called skywave or "skip" propagation. Thus shortwave radio can be used for communication over very long distances, in contrast to radio waves of higher frequency, which travel in straight lines (line-of-sight propagation) and are generally limited by the visual horizon, about 64 km (40 miles). Shortwave broadcasts of radio pr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Daylight Saving Time
Daylight saving time (DST), also referred to as daylight savings time, daylight time (Daylight saving time in the United States, United States and Daylight saving time in Canada, Canada), or summer time (British Summer Time, United Kingdom, Summer time in Europe, European Union, and others), is the practice of advancing clocks to make better use of the longer daylight available during summer so that darkness falls at a later clock time. The standard implementation of DST is to set clocks forward by one hour in spring (season), spring or late winter, and to set clocks back by one hour to standard time in the autumn (or ''fall'' in North American English, hence the mnemonic: "spring forward and fall back"). Overview As of 2023, around 34 percent of the world's countries use DST. Some countries observe it only in some regions. In Canada, all of Yukon Time Zone, Yukon, most of Time in Saskatchewan, Saskatchewan, and parts of Nunavut, Ontario, British Columbia and Quebec do not ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mint Stamp
In philately, a mint stamp is one which is unused, has never been mounted and has the original postage stamp gum, gum, (if issued with gum).James A. Mackay, Mackay, James. ''Stamp Collecting: Philatelic Terms Illustrated''. 4th edition. London: Stanley Gibbons, 2003, p.88. Youngblood, Wayne L. ''All about Stamps''. Iola WI: Krause Publications, 2000, p.109. The term applies equally to postage stamps and revenue stamps. In practice, the term is used within philately to refer to any stamp that appears to be unused with gum. It also includes those without gum but only when they have been issued without gum. To avoid confusion the various states of mint can be distinguished in the abbreviations stated under "Variations". Variations Variations of the term ''mint'' include: *Mint hinged (MH) – the stamp is unused but has been previously hinged. Remains of the hinge or gum disturbance are visible. *Mounted mint (MM) – the same as Mint hinged. *Mint no gum (MNG) – the stamp is ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
International Reply Coupon
An international reply coupon (IRC) is a coupon that can be exchanged for one or more postage stamps representing the minimum postage for an unregistered priority airmail letter sent to another Universal Postal Union (UPU) member country. IRCs are accepted by all UPU member countries. UPU member postal services are obliged to exchange an IRC for postage, but are not obliged to sell them. The purpose of the IRC is to allow a person to send someone in another country a letter, along with the cost of postage for a reply. If the addressee is within the same country, there is no need for an IRC because a self-addressed stamped envelope (SASE) or return postcard will suffice; but if the addressee is in another country an IRC removes the necessity of acquiring foreign Mail, postage or sending appropriate currency. Description International reply coupons (in French, ''Coupons-Réponse Internationaux'') are printed in blue ink on paper that has the letters "UPU" in large characters i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fading
In wireless communications, fading is the variation of signal attenuation over variables like time, geographical position, and radio frequency. Fading is often modeled as a random process. In wireless systems, fading may either be due to multipath propagation, referred to as multipath-induced fading, weather (particularly rain), or shadowing from obstacles affecting the wave propagation, sometimes referred to as shadow fading. A fading channel is a communication channel that experiences fading. Key concepts The presence of reflectors in the environment surrounding a transmitter and receiver create multiple paths that a transmitted signal can traverse. As a result, the receiver sees the superposition of multiple copies of the transmitted signal, each traversing a different path. Each signal copy will experience differences in attenuation, delay and phase shift while traveling from the source to the receiver. This can result in either constructive or destructive inter ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Noise (radio)
In radio reception, radio noise (commonly referred to as radio static) is unwanted random radio frequency electrical signals, fluctuating voltages, always present in a radio receiver in addition to the desired radio signal. Radio noise is a combination of natural electromagnetic atmospheric noise ("spherics", static) created by electrical processes in the atmosphere like lightning; human-made radio frequency interference () from other electrical devices picked up by the receiver's antenna; and thermal noise present in the receiver input circuits, mostly caused by the random thermal motion of molecules inside resistors. Effects of noise on radio Radio noise near in frequency to a received radio signal (in the receiver's passband) interferes ( ) with the operation of the receiver's circuitry. The level of noise determines the maximum sensitivity and reception range of a radio receiver; if no noise were picked up with radio signals, even weak transmissions could be received at ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Adjacent-channel Interference
Adjacent-channel interference (ACI) is interference caused by extraneous power from a signal in an adjacent channel. ACI may be caused by inadequate filtering (such as incomplete filtering of unwanted modulation products in FM systems), improper tuning or poor frequency control (in the reference channel, the interfering channel or both). ACI is distinguished from crosstalk. Origin The adjacent-channel interference which receiver A experiences from a transmitter B is the sum of the power that B emits into A's channel—known as the "unwanted emission", and represented by the ACLR (Adjacent Channel Leakage Ratio)—and the power that A picks up from B's channel, which is represented by the ACS (Adjacent Channel Selectivity). B emitting power into A's channel is called adjacent-channel leakage (unwanted emissions). It occurs for two reasons. First, because RF filters require a roll-off, and do not eliminate a signal completely. Second, due to intermodulation in B's amplifiers ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Co-channel Interference
Co-channel interference or CCI is crosstalk from two different radio transmitters using the same channel. Co-channel interference can be caused by many factors from weather conditions to administrative and design issues. Co-channel interference may be controlled by various radio resource management schemes. Cellular mobile networks In cellular mobile communication (GSM & LTE Systems, for instance), frequency spectrum is a precious resource which is divided into non-overlapping spectrum bands which are assigned to different cells (In cellular communications, a cell refers to the hexagonal/circular area around the base station antenna). However, after certain geographical distance, these frequency bands are re-used, i.e. the same spectrum bands are reassigned to other distant cells. The co-channel interference arises in the cellular mobile networks owing to this phenomenon of frequency reuse. Thus, besides the intended signal from within the cell, signals at the same freque ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
The Sports Network
The Sports Network (TSN) is a Canadian English language discretionary sports specialty channel owned by the Sports Network Inc., a subsidiary of CTV Specialty Television, which is also a joint venture of Bell Media (70%), also owned by BCE Inc. and ESPN Inc. (30%), itself a subsidiary of the Walt Disney Company. TSN was established by the Labatt Brewing Company in 1984 as part of the first group of Canadian specialty cable channels. In 2013, TSN was the largest specialty channel in Canada in terms of gross revenue, with a total of in revenue. TSN broadcasts primarily from studio facilities located at Bell Media Agincourt in the Scarborough neighbourhood of Toronto, Ontario. Stewart Johnston currently serves as president of TSN, a position he has held since 2010. TSN's networks focus on sports-related programming, including live and recorded event telecasts, sports talk shows, and other original programming. History Early history Licensed by the Canadian Radio-televisi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Broadcast Syndication
Broadcast syndication is the practice of content owners leasing the right to broadcast their content to other television stations or radio stations, without having an official broadcast network to air it on. It is common in the United States where broadcast programming is scheduled by television networks with local independent Network affiliate, affiliates. Syndication is less widespread in the rest of the world, as most countries have centralized networks or television stations without local affiliates. Shows can be syndicated internationally, although this is less common. Three common types of syndication are: ''first-run'' syndication, which is programming that is broadcast for the first time as a syndicated show and is made specifically for the purpose of selling it into syndication; ''Off-network'' syndication (colloquially called a "rerun"), which is the licensing of a program whose first airing was on stations inside the Television broadcaster, television network that prod ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Logbook
A logbook (or log book) is a record used to record states, events, or conditions applicable to complex machines or the personnel who operate them. Logbooks are commonly associated with the operation of aircraft, nuclear plants, particle accelerators, and ships (among other applications). The term ''logbook'' originated with the ship's log, a maritime record of important events in the management, operation, and navigation of a ship. The captain was responsible for keeping a log, as a minimum, of navigational wind, speed, direction and position. Format Logbooks come in many varieties, but they are sometimes standardized in form and/or content within certain organizations or industries. In some applications like flight training or trucking hours of service, they contain specific information used to satisfy legal requirements. Electronic logbooks Prior to the advent of mobile computing, logbooks were almost exclusively printed and bound in hard copy form. While physical ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
