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Scanner (radio)
A scanner (also referred to as a radio scanner) is a radio receiver that can automatically tune, or ''scan'', two or more discrete frequencies, stopping when it finds a signal on one of them and then continuing to scan other frequencies when the initial transmission ceases. The term ''scanner'' generally refers to a communications receiver that is primarily intended for monitoring VHF and UHF landmobile radio systems, as opposed to, for instance, a receiver used to monitor international shortwave transmissions. More often than not, these scanners can also tune to different types of modulation as well ( AM, FM, WFM, etc.). Early scanners were slow, bulky, and expensive. Today, modern microprocessors have enabled scanners to store thousands of channels and monitor hundreds of channels per second. Recent models can follow trunked radio systems and decode APCO-P25 digital transmissions. Both hand held and desktop models are available. Scanners are often used to monitor police, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
CB Radio
Citizens band radio (also known as CB radio), used in many countries, is a land mobile radio system, a system allowing short-distance person-to-many persons bidirectional voice communication among individuals, using two way radios operating on 40 channels near 27 MHz (11 m) in the high frequency (a.k.a. shortwave) band. Citizens band is distinct from other personal radio service allocations such as FRS, GMRS, MURS, UHF CB and the Amateur Radio Service ( "ham" radio). In many countries, CB operation does not require a license, and (unlike amateur radio) it may be used for business or personal communications. Like many other land mobile radio services, multiple radios in a local area share a single frequency channel, but only one can transmit at a time. The radio is normally in receive mode to receive transmissions of other radios on the channel; when users want to talk they press a "push to talk" button on their radio, which turns on their transmitter. Users o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hobbyist
A hobby is considered to be a regular activity that is done for enjoyment, typically during one's leisure time. Hobbies include collecting themed items and objects, engaging in creative and artistic pursuits, playing sports, or pursuing other amusements. Participation in hobbies encourages acquiring substantial skills and knowledge in that area. A list of hobbies changes with renewed interests and developing fashions, making it diverse and lengthy. Hobbies tend to follow trends in society, for example stamp collecting was popular during the nineteenth and twentieth centuries as postal systems were the main means of communication, while video games are more popular nowadays following technological advances. The advancing production and technology of the nineteenth century provided workers with more leisure time to engage in hobbies. Because of this, the efforts of people investing in hobbies has increased with time. Hobbyists may be identified under three sub-categories: ''c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Antenna (electronics)
In radio engineering, an antenna or aerial is the interface between radio waves propagating through space and electric currents moving in metal conductors, used with a transmitter or receiver. In transmission, a radio transmitter supplies an electric current to the antenna's terminals, and the antenna radiates the energy from the current as electromagnetic waves (radio waves). In reception, an antenna intercepts some of the power of a radio wave in order to produce an electric current at its terminals, that is applied to a receiver to be amplified. Antennas are essential components of all radio equipment. An antenna is an array of conductors ( elements), electrically connected to the receiver or transmitter. Antennas can be designed to transmit and receive radio waves in all horizontal directions equally (omnidirectional antennas), or preferentially in a particular direction ( directional, or high-gain, or “beam” antennas). An antenna may include components not connec ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Two-tone Sequential
In a conventional, analog two-way radio system, a standard radio has ''noise squelch'' or ''carrier squelch'', which allows a radio to receive all transmissions. Selective calling is used to address a subset of all two-way radios on a single radio frequency channel. Where more than one user is on the same channel (co-channel users), selective calling can address a subset of all receivers or can direct a call to a single radio. Selective calling features fit into two major categories—''individual calling'' and ''group calling''. Individual calls generally have longer time-constants: it takes more air-time to call an individual radio unit than to call a large group of radios. Selective calling is akin to the use of a lock on a door. A radio with carrier squelch is unlocked and will let any signal in. Selective calling locks out all signals except ones with the correct "key", in this case a specific digital code. Selective calling systems can overlap; a radio may have (group call) ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
NOAA Weather Radio All Hazards
NOAA Weather Radio NWR; also known as NOAA Weather Radio All Hazards is an automated 24-hour network of VHF FM weather radio stations in the United States (U.S.) that broadcast weather information directly from a nearby National Weather Service office. The routine programming cycle includes local or regional weather forecasts, synopsis, climate summaries or zone/lake/coastal waters forecasts (when applicable). During severe conditions the cycle is shortened into: hazardous weather outlooks, short-term forecasts, special weather statements or tropical weather summaries (the first two aren't normally broadcast in most offices). It occasionally broadcasts other non-weather related events such as national security statements, natural disaster information, environmental and public safety statements (such as an AMBER Alert), civil emergencies, fires, evacuation orders, and other hazards sourced from the Federal Communications Commission's (FCC) Emergency Alert System. NOAA Weather R ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Marine (ocean)
The ocean (also the sea or the world ocean) is the body of salt water that covers approximately 70.8% of the surface of Earth and contains 97% of Earth's water. An ocean can also refer to any of the large bodies of water into which the world ocean is conventionally divided."Ocean." ''Merriam-Webster.com Dictionary'', Merriam-Webster, |
Air Traffic Control
Air traffic control (ATC) is a service provided by ground-based air traffic controllers who direct aircraft on the ground and through a given section of controlled airspace, and can provide advisory services to aircraft in non-controlled airspace. The primary purpose of ATC worldwide is to prevent collisions, organize and expedite the flow of air traffic, and provide information and other support for pilots. Air traffic controllers monitor the location of aircraft in their assigned airspace by radar and communicate with the pilots by radio. To prevent collisions, ATC enforces traffic separation rules, which ensure each aircraft maintains a minimum amount of empty space around it at all times. In many countries, ATC provides services to all private, military, and commercial aircraft operating within its airspace. Depending on the type of flight and the class of airspace, ATC may issue ''instructions'' that pilots are required to obey, or ''advisories'' (known as ''flight infor ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
CTCSS
In telecommunications, Continuous Tone-Coded Squelch System or CTCSS is one type of in-band signaling that is used to reduce the annoyance of listening to other users on a shared two-way radio communication channel. (See squelch.) It is sometimes referred to as tone squelch. It does this by adding a low frequency audio tone to the voice. Where more than one group of users is on the same radio frequency (called ''co-channel users''), CTCSS circuitry mutes those users who are using a different CTCSS tone or no CTCSS. It is sometimes referred to as a sub-channel, but this is a misnomer because no additional channels are created. All users with different CTCSS tones on the same channel are still transmitting on the identical radio frequency, and their transmissions interfere with each other; however; the interference is masked under most conditions. The CTCSS feature also does not offer any security. A receiver with just a carrier or noise squelch does not suppress any sufficiently s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Digital-Coded Squelch
In telecommunications, squelch is a circuit function that acts to suppress the audio (or video) output of a receiver in the absence of a strong input signal. Essentially, squelch is a specialized type of noise gate designed to suppress weak signals. Squelch is used in two-way radios and VHF/UHF radio scanners to eliminate the sound of noise when the radio is not receiving a desired transmission. Carrier squelch A carrier squelch or noise squelch is the most simple variant of all. It operates strictly on the signal strength, such as when a television mutes the audio or blanks the video on "empty" channels, or when a walkie-talkie mutes the audio when no signal is present. In some designs, the squelch threshold is preset. For example, television squelch settings are usually preset. Receivers in base stations, or repeaters at remote mountain top sites, are usually not adjustable remotely from the control point. In two-way radios (also known as radiotelephones), the received si ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Uniden BCT-15 Deck In Bracket-left
() is a Japanese company in the wireless communication industry. History Uniden was established on February 7, 1966, by its founder Hidero Fujimoto as "Uni Electronics Corp". Uniden became a well-known brand in the 1970s by manufacturing and marketing millions of citizens band radios (CB), under the Uniden brand as well as many for popular private brand labels such as Clegg (amateur transceivers), Cobra, Craig, Fanon-Courier, Midland (only certain clone models, originals were made by Cybernet), President, Teaberry, Stalker, Super Star, Teledyne-Olson, Pearce Simpson, Realistic, Regency, Robyn and many European brands such as Zodiac, Stabo and Inno-Hit. Uniden also marketed CB Radios in the UK under the Uniden and Uniace brands during the late 1970s. During the 1980s, Uniden grew to become the world's largest manufacturer of cordless telephones in addition to television satellite equipment, mobile radios, advanced marine electronics and radio scanners (the latter under brand ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Consumer Electronics Show
CES (; formerly an initialism for Consumer Electronics Show) is an annual trade show organized by the Consumer Technology Association (CTA). Held in January at the Las Vegas Convention Center in Winchester, Nevada, United States, the event typically hosts presentations of new products and technologies in the consumer electronics industry. History The first CES was held in June 1967 in New York City. It was a spinoff from the Chicago Music Show, which, until then, had served as the main event for exhibiting consumer electronics. The event had 17,500 attenders and over 100 exhibitors; the kickoff speaker was Motorola chairman Bob Galvin. From 1978 to 1994, CES was held twice each year: once in January in Las Vegas known for ''Winter Consumer Electronics Show (WCES)'' and once in June in Chicago, known as ''Summer Consumer Electronics Show (SCES)''. The winter show was successfully held in Las Vegas in 1995 as planned. However, since the summer Chicago shows were beginning to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
