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PL Tone
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 Squelch, carrier or noise squelch does not suppress any suffic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Telecommunications
Telecommunication is the transmission of information by various types of technologies over wire, radio, optical, or other electromagnetic systems. It has its origin in the desire of humans for communication over a distance greater than that feasible with the human voice, but with a similar scale of expediency; thus, slow systems (such as postal mail) are excluded from the field. The transmission media in telecommunication have evolved through numerous stages of technology, from beacons and other visual signals (such as smoke signals, semaphore telegraphs, signal flags, and optical heliographs), to electrical cable and electromagnetic radiation, including light. Such transmission paths are often divided into communication channels, which afford the advantages of multiplexing multiple concurrent communication sessions. ''Telecommunication'' is often used in its plural form. Other examples of pre-modern long-distance communication included audio messages, such as coded d ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Electronic Industries Alliance
The Electronic Industries Alliance (EIA; until 1997 Electronic Industries Association) was an American standards and trade organization composed as an alliance of trade associations for electronics manufacturers in the United States. They developed standards to ensure the equipment of different manufacturers was compatible and interchangeable. The EIA ceased operations on February 11, 2011, but the former sectors continue to serve the constituencies of EIA. History In 1924, 50 radio manufacturers in Chicago formed a trade group called the ''Associated Radio Manufacturers''. This organization was designed to control the licensing of the large number of radio patents so that each member could have access to all the relevant patents necessary to build radio transmitters, antennas and receivers. Over time, new electronic technologies brought new members, non-manufacturer members, and name changes. Names in chronological order: * 1924 – ''Associated Radio Manufacturers'' * ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Signaling (telecommunications)
In telecommunication, signaling is the use of signals for controlling communications. This may constitute an information exchange concerning the establishment and control of a telecommunication circuit and the management of the network. Classification Signaling systems may be classified based on several principal characteristics. In-band and out-of-band signaling In the public switched telephone network (PSTN), in-band signaling is the exchange of call control information within the same physical channel, or within the same frequency band, that the telephone call itself is using. An example is dual-tone multi-frequency signaling (DTMF), which is used on most telephone lines to customer premises. Out-of-band signaling is telecommunication signaling on a dedicated channel separate from that used for the telephone call. Out-of-band signaling has been used since Signaling System No. 6 (SS6) was introduced in the 1970s, and also in Signalling System No. 7 (SS7) in 1980 which becam ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Radiotelephony Procedure
Radiotelephony procedure (also on-air protocol and voice procedure) includes various techniques used to clarify, simplify and standardize spoken communications over two-way radios, in use by the armed forces, in civil aviation, police and fire dispatching systems, citizens' band radio (CB), and amateur radio. Voice procedure communications are intended to maximize clarity of spoken communication and reduce errors in the verbal message by use of an accepted nomenclature. It consists of a signalling protocol such as the use of abbreviated codes like the CB radio ten-code, Q codes in amateur radio and aviation, police codes, etc., and jargon. Some elements of voice procedure are understood across many applications, but significant variations exist. The armed forces of the NATO countries have similar procedures in order to make cooperation easier. The impacts of having radio operators who are not well-trained in standard procedures can cause significant operational problems and del ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
PMR446
PMR446 (Private Mobile Radio, 446 MHz) is a licence exempt service in the UHF radio frequency band and is available for business and personal use in most countries throughout the European Union. PMR446 is typically used for small-site, same-building and line of sight outdoor activities. Equipment used ranges from consumer-grade to professional quality walkie-talkies (similar to those used for FRS/ GMRS in the United States and Canada). Depending on surrounding terrain range can vary from a few hundred metres (in a city) to a few kilometres (flat countryside) to many kilometres from high ground. Historically, analogue FM is used but a digital voice mode has been available in radios conforming to digital private mobile radio (dPMR446) and digital mobile radio (DMR Tier 1) standards designed by ETSI. Originally 8 channels were available in analogue mode but this has now been increased to 16 channels. Typically PMR446 is used for both recreational and business use, additi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Family Radio Service
The Family Radio Service (FRS) is an improved walkie-talkie radio system authorized in the United States since 1996. This personal radio service uses channelized frequencies around 462 and 467 MHz in the ultra high frequency (UHF) band. It does not suffer the interference effects found on citizens' band (CB) at 27 MHz, or the 49 MHz band also used by cordless telephones, toys, and baby monitors. FRS uses frequency modulation (FM) instead of amplitude modulation (AM). Since the UHF band has different radio propagation characteristics, short-range use of FRS may be more predictable than the more powerful license-free radios operating in the HF CB band. Initially proposed by RadioShack in 1994 for use by families, FRS has also seen significant adoption by business interests, as an unlicensed, low-cost alternative to the business band. New rules issued by the FCC in May 2017 clarify and simplify the overlap between FRS and General Mobile Radio Service (GMRS) radio serv ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Amateur Radio
Amateur radio, also known as ham radio, is the use of the radio frequency spectrum for purposes of non-commercial exchange of messages, wireless experimentation, self-training, private recreation, radiosport, contesting, and emergency communications. The term "amateur" is used to specify "a duly authorised person interested in radioelectric practice with a purely personal aim and without pecuniary interest;" (either direct monetary or other similar reward) and to differentiate it from commercial broadcasting, public safety (such as police and fire), or professional two-way radio services (such as maritime, aviation, taxis, etc.). The amateur radio service (''amateur service'' and '' amateur-satellite service'') is established by the International Telecommunication Union (ITU) through the Radio Regulations. National governments regulate technical and operational characteristics of transmissions and issue individual station licenses with a unique identifying call sign, which ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
AN/PRC-148
The AN/PRC-148 Multiband Inter/Intra Team Radio (MBITR) is the most widely fielded handheld multiband, tactical software-defined radio, used by NATO forces around the world. The radio is built by Thales Communications, a subsidiary of the France-based Thales Group. The designation AN/PRC translates to Army/Navy Portable Radio used for two way Communications, according to Joint Electronics Type Designation System guidelines. The MBITR was developed by the United States Special Operations Command (USSOCOM) and Thales Communications in the 1990s and went into production in 1994, to address the need for a secure multiband handheld radio.Thales PRC-148 JEM: The First Tactically Deployed JTRS Radio? Defense Industry Daily ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
AN/VRC-12
The AN/VRC-12 is the lowest-numbered element of a family of vehicular VHF- FM synthesized vehicular radio communications systems developed by Avco Corporation and introduced around 1963 and used extensively by the U.S. military during the Vietnam War and for many years after. It replaced the earlier AN/GRC-3 through 8 series and was, in turn, replaced by the Single Channel Ground and Airborne Radio System (SINCGARS) in the early 1990s. The sets were manufactured by its original developer, Avco based in Cincinnati, Oh (originally by its Electronic & Ordnance Div., Evendale, Ohio), and Magnavox, Ft. Wayne, Indiana (with LTV Electrosystems, Inc. and Memcor, Inc., supplying certain components, such as receivers and transmitters.) Texas Instruments was one of the principal bidders that proposed improved, ultra-reliable (failure-free) variant of VRC-12 in the late 1960s, but failed to win the competition. RCA bid for ultra-reliable variant in the early 1970s was also unsuccessful. Back ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
AN/PRC-119
Single Channel Ground and Airborne Radio System (SINCGARS) is a Combat-net radio (CNR) used by U.S. and allied military forces. The CNR network is designed around three systems: SINCGARS, the high frequency (HF) radio, and the SC tactical satellite (TACSAT). Each system has different capabilities and transmission characteristics. SINCGARS is a family of user-owned and operated, very high frequency-frequency modulation (VHF-FM) CNRs. In the CNR network, the SINCGARS’ primary role is voice transmission for command and control (C2) between surface and airborne C2 assets. SINCGARS can transmit and receive secure data and facsimile transmissions through simple connections with various data terminal equipment. SINCGARS features provide communications interoperability for the Army, Marine, Navy, and Air Force, thus contributing to successful combat operations. It is also consistent with North Atlantic Treaty Organization interoperability requirements. The radios, which is hand ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
AN/PRC-152
The AN/PRC-152 Multiband Handheld Radio, also known as Harris Falcon III, is a portable, compact, tactical software-defined combat-net radio manufactured by Harris Corporation. It is compliant without waivers to the Joint Tactical Radio System (JTRS) Software Communications Architecture (SCA). It has received NSA certification for the transmission of Top Secret data. The designation AN/PRC signifies Army/Navy Portable Radio used for two way Communications and is based on the Joint Electronics Type Designation System guidelines. Users The AN/PRC-152 radio is currently in use with the US Navy Explosive Ordnance Disposal (EOD) teams in their MRAP JERRV vehicles. As of 2005, 1,300 radios have also been fielded in vehicles by the US Army. and more than 8,600 have been fielded by the U.S. Marines. An undetermined number are in use by the US Air Force in Iraq and Afghanistan. More recently the radio was photographed with Prince Harry, then a 23-year-old second lieutenant in the House ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
AN/PRC-113
AN/PRC 113 Radio Set is a manpack, portable VHF and UHF AM combat radio transceiver manufactured by Magnavox America.Olive-Drab. (2011). An/prc-113 manpack radio. Retrieved from http://olive-drab.com/od_electronics_anprc113.php In the Joint Electronics Type Designation System (JETDS), AN/PRC translates to "Army/Navy, Portable, Radio, Communication. History The AN/PRC-113 is a tactical, short range, manpack, ground to air / air to ground / ground to ground radio used primarily by Forward Air Controller (FAC) teams, Forward Observers (FO) and Marine Air Command and Control agencies. It was also used by some units in the active army, national guard and reserves, but mostly by support elements. It was first introduced by the Magnavox Corporation in 1986 and was quickly well liked by ground troops because of its simplicity and ease of use. Technical characteristics The AN/PRC 113 consists of the RT-1319 transceiver and minor components.Tasker, A.D. (2000). U.S. Military Portable R ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
