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PL-259
The UHF connector is a name for a threaded RF connector. The connector design was invented in the 1930s for use in the radio industry, and is a shielded form of the "banana plug". It is a widely used standard connector for HF transmission lines on full-sized radio equipment, with BNC connectors predominating for smaller, hand-held equipment. The name "UHF" is a source of confusion, since the name of the connectors did not change when the frequency ranges were renamed. The design was named during an era when "UHF" meant frequencies over 30 MHz. Today, Ultra high frequency (UHF) instead refers to frequencies between 300 MHz and 3 GHz"UHF" is 300 MHz and 3 GHz in both the ITU and IEEE radio band designation systems and the range of frequencies formerly known as UHF is now called "VHF". Unlike modern connector designs that replaced it, no active specification or standard exists to govern the mechanical and electrical characteristics of the so-called "UHF" ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Banana Plug
A banana connector (commonly banana plug for the male, banana socket or banana jack for the female) is a single-wire (one conductor) electrical connector used for joining wires to equipment. The term 4 mm connector is also used, especially in Europe, although not all banana connectors will mate with 4 mm parts, and 2 mm banana connectors exist. Various styles of banana plug contacts exist, all based on the concept of spring metal applying outward force into the unsprung cylindrical jack to produce a snug fit with good electrical conductivity. Common types include: a solid pin split lengthwise and splayed slightly, a tip of four leaf springs, a cylinder with a single leaf spring on one side, a bundle of stiff wire, a central pin surrounded by a multiple-slit cylinder with a central bulge, or simple sheet spring metal rolled into a nearly complete cylinder. The plugs are frequently used to terminate patch cords for electronic test equipment such as laboratory power ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
N Connector
The N connector (also, type-N connector) is a threaded, weatherproof, medium-size RF connector used to join coaxial cables. It was one of the first connectors capable of carrying microwave-frequency signals, and was invented in the 1940s by Paul Neill of Bell Labs, after whom the connector is named. Design The interface specifications for the N and many other connectors are referenced in MIL-STD-348. Originally, the connector was designed to carry signals at frequencies up to 1 GHz in military applications, but today's common Type N easily handles frequencies up to 11 GHz. More recent precision enhancements to the design by Julius Botka at Hewlett Packard have pushed this to 18 GHz. The male connector is hand-tightened (though versions with a hex nut are also available) and has an air gap between the center and outer conductors. The coupling has a -24 UNEF thread. Amphenol suggests tightening to a torque of , while Andrew Corporation suggest for their hex nut ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
RF Connector
A coaxial RF connector (radio frequency connector) is an electrical connector designed to work at radio frequencies in the multi-megahertz range. RF connectors are typically used with coaxial cables and are designed to maintain the shielding that the coaxial design offers. Better models also minimize the change in transmission line impedance at the connection in order to reduce signal reflection and power loss. As the frequency increases, transmission line effects become more important, with small impedance variations from connectors causing the signal to reflect rather than pass through. An RF connector must not allow external signals into the circuit through electromagnetic interference and capacitive pickup. Mechanically, RF connectors may provide a fastening mechanism ( thread, bayonet, braces, blind mate) and springs for a low ohmic electric contact while sparing the gold surface, thus allowing very high mating cycles and reducing the insertion force. Research activit ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Israel
Israel (; he, יִשְׂרָאֵל, ; ar, إِسْرَائِيل, ), officially the State of Israel ( he, מְדִינַת יִשְׂרָאֵל, label=none, translit=Medīnat Yīsrāʾēl; ), is a country in Western Asia. It is situated on the southeastern shore of the Mediterranean Sea and the northern shore of the Red Sea, and shares borders with Lebanon to the north, Syria to the northeast, Jordan to the east, and Egypt to the southwest. Israel also is bordered by the Palestinian territories of the West Bank and the Gaza Strip to the east and west, respectively. Tel Aviv is the economic and technological center of the country, while its seat of government is in its proclaimed capital of Jerusalem, although Israeli sovereignty over East Jerusalem is unrecognized internationally. The land held by present-day Israel witnessed some of the earliest human occupations outside Africa and was among the earliest known sites of agriculture. It was inhabited by the Canaanites ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Marine VHF Radio
Marine VHF radio is a worldwide system of two way radio transceivers on ships and watercraft used for bidirectional voice communication from ship-to-ship, ship-to-shore (for example with harbormasters), and in certain circumstances ship-to-aircraft. It uses FM channels in the very high frequency (VHF) radio band in the frequency range between 156 and 174 MHz, inclusive, designated by the International Telecommunication Union as the ''VHF maritime mobile band''. In some countries additional channels are used, such as the L and F channels for leisure and fishing vessels in the Nordic countries (at 155.5–155.825 MHz). Transmitter power is limited to 25 watts, giving them a range of about . Marine VHF radio equipment is installed on all large ships and most seagoing small craft. It is also used, with slightly different regulation, on rivers and lakes. It is used for a wide variety of purposes, including marine navigation and traffic control, summoning rescue servic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Citizens Band 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 ... [...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 mus ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kilowatt
The watt (symbol: W) is the unit of power or radiant flux in the International System of Units (SI), equal to 1 joule per second or 1 kg⋅m2⋅s−3. It is used to quantify the rate of energy transfer. The watt is named after James Watt (1736–1819), an 18th-century Scottish inventor, mechanical engineer, and chemist who improved the Newcomen engine with his own steam engine in 1776. Watt's invention was fundamental for the Industrial Revolution. Overview When an object's velocity is held constant at one metre per second against a constant opposing force of one newton, the rate at which work is done is one watt. : \mathrm In terms of electromagnetism, one watt is the rate at which electrical work is performed when a current of one ampere (A) flows across an electrical potential difference of one volt (V), meaning the watt is equivalent to the volt-ampere (the latter unit, however, is used for a different quantity from the real power of an electrical circuit). : ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Very High Frequency
Very high frequency (VHF) is the ITU designation for the range of radio frequency electromagnetic waves ( radio waves) from 30 to 300 megahertz (MHz), with corresponding wavelengths of ten meters to one meter. Frequencies immediately below VHF are denoted high frequency (HF), and the next higher frequencies are known as ultra high frequency (UHF). VHF radio waves propagate mainly by line-of-sight, so they are blocked by hills and mountains, although due to refraction they can travel somewhat beyond the visual horizon out to about 160 km (100 miles). Common uses for radio waves in the VHF band are Digital Audio Broadcasting (DAB) and FM radio broadcasting, television broadcasting, two-way land mobile radio systems (emergency, business, private use and military), long range data communication up to several tens of kilometers with radio modems, amateur radio, and marine communications. Air traffic control communications and air navigation systems (e.g. VOR and ILS) wo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Shortwave
Shortwave radio is radio transmission using shortwave (SW) radio frequencies. There is no official definition of the band, but the range always includes all of the high frequency band (HF), which extends from 3 to 30 MHz (100 to 10 metres); above the medium frequency band (MF), to 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 limited by the visual horizon, about 64 km (40 miles). Shortwave broadcasts of radio programs played an important role in the early days of radio ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Surge Impedance
The characteristic impedance or surge impedance (usually written Z0) of a uniform transmission line is the ratio of the amplitudes of voltage and current of a single wave propagating along the line; that is, a wave travelling in one direction in the absence of reflections in the other direction. Alternatively, and equivalently, it can be defined as the input impedance of a transmission line when its length is infinite. Characteristic impedance is determined by the geometry and materials of the transmission line and, for a uniform line, is not dependent on its length. The SI unit of characteristic impedance is the ohm. The characteristic impedance of a lossless transmission line is purely real, with no reactive component. Energy supplied by a source at one end of such a line is transmitted through the line without being dissipated in the line itself. A transmission line of finite length (lossless or lossy) that is terminated at one end with an impedance equal to the characteris ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Joint Electronics Type Designation System
The Joint Electronics Type Designation System (JETDS), which was previously known as the Joint Army-Navy Nomenclature System (AN System. JAN) and the Joint Communications-Electronics Nomenclature System, is a method developed by the U.S. War Department during World War II for assigning an unclassified designator to electronic equipment. In 1957, the JETDS was formalized in MIL-STD-196. Computer software and commercial unmodified electronics for which the manufacturer maintains design control are not covered. Applicability Electronic material, from a military point of view, generally includes those electronic devices employed in data processing, detection and tracking (underwater, sea, land-based, air and space), recognition and identification, communications, aids to navigation, weapons control and evaluation, flight control, and electronics countermeasures. Nomenclature is assigned to: * Electronic materiel of military design * Commercial electronic materiel that has been modifi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
