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Coaxial Cabling
Coaxial cable, or coax (pronounced ), is a type of electrical cable consisting of an inner conductor surrounded by a concentric conducting shield, with the two separated by a dielectric ( insulating material); many coaxial cables also have a protective outer sheath or jacket. The term ''coaxial'' refers to the inner conductor and the outer shield sharing a geometric axis. Coaxial cable is a type of transmission line, used to carry high-frequency electrical signals with low losses. It is used in such applications as telephone trunk lines, broadband internet networking cables, high-speed computer data buses, cable television signals, and connecting radio transmitters and receivers to their antennas. It differs from other shielded cables because the dimensions of the cable and connectors are controlled to give a precise, constant conductor spacing, which is needed for it to function efficiently as a transmission line. Coaxial cable was used in the first (1858) and following ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
RG-59
RG-59/U is a specific type of coaxial cable, often used for low-power video and Radio frequency, RF signal connections. The cable has a characteristic impedance of 75 Ohm (unit), ohms, and a capacitance of around 20pF/ft (60pF/m). The 75 ohm impedance matches a dipole antenna in free space. ''RG'' (for ''radio guide'') was originally a unit indicator for bulk radio frequency (RF) cable in the U.S. military's Joint Electronics Type Designation System. The suffix ''/U'' means ''for general utility use''. The number ''59'' was assigned sequentially. The ''RG'' unit indicator is no longer part of the JETDS system (MIL-STD-196E) and cable sold today under the RG-59 label does not necessarily meet military specifications. RG-59 is often used at baseband video frequencies, such as composite video. It may also be used for broadcast frequencies, but its high-frequency losses are too high to allow its use over long distances; in these applications, RG-6 or RG-11 are used instead. I ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Differential Signaling
Differential signalling is a method for electrically transmitting information using two complementary signals. The technique sends the same electrical signal as a differential pair of signals, each in its own conductor. The pair of conductors can be wires in a twisted-pair or ribbon cable or traces on a printed circuit board. Electrically, the two conductors carry voltage signals which are equal in magnitude, but of opposite polarity. The receiving circuit responds to the difference between the two signals, which results in a signal with a magnitude twice as large. The symmetrical signals of differential signalling may be referred to as ''balanced'', but this term is more appropriately applied to balanced circuits and balanced lines which reject common-mode interference when fed into a differential receiver. Differential signalling does not make a line balanced, nor does noise rejection in balanced circuits require differential signalling. Differential signalli ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Coaxial Cable Cutaway
In geometry, coaxial means that several three-dimensional linear or planar forms share a common axis. The two-dimensional analog is ''concentric''. Common examples: A coaxial cable has a wire conductor in the centre (D), a circumferential outer conductor (B), and an insulating medium called the dielectric (C) separating these two conductors. The outer conductor is usually sheathed in a protective PVC outer jacket (A). All these have a common axis. The dimension and material of the conductors and insulation determine the cable's characteristic impedance and attenuation at various frequencies. Coaxial rotors are a three-dimensional planar structure: a pair of helicopter rotors (wings) mounted one above the other on concentric shafts, with the same axis of rotation (but turning in opposite directions). In loudspeaker design, coaxial speakers are a loudspeaker system in which the individual drivers are mounted close to one another on the same axis, and thus radiate sound along ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Electrical Conductor
In physics and electrical engineering, a conductor is an object or type of material that allows the flow of charge (electric current) in one or more directions. Materials made of metal are common electrical conductors. The flow of negatively charged electrons generates electric current, positively charged holes, and positive or negative ions in some cases. In order for current to flow within a closed electrical circuit, one charged particle does not need to travel from the component producing the current (the current source) to those consuming it (the loads). Instead, the charged particle simply needs to nudge its neighbor a finite amount, who will nudge ''its'' neighbor, and on and on until a particle is nudged into the consumer, thus powering it. Essentially what is occurring is a long chain of momentum transfer between mobile charge carriers; the Drude model of conduction describes this process more rigorously. This momentum transfer model makes metal an ideal choice f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Electromagnetic Field
An electromagnetic field (also EM field) is a physical field, varying in space and time, that represents the electric and magnetic influences generated by and acting upon electric charges. The field at any point in space and time can be regarded as a combination of an electric field and a magnetic field. Because of the interrelationship between the fields, a disturbance in the electric field can create a disturbance in the magnetic field which in turn affects the electric field, leading to an oscillation that propagates through space, known as an ''electromagnetic wave''. The way in which charges and currents (i.e. streams of charges) interact with the electromagnetic field is described by Maxwell's equations and the Lorentz force law. Maxwell's equations detail how the electric field converges towards or diverges away from electric charges, how the magnetic field curls around electrical currents, and how changes in the electric and magnetic fields influence each other. The Lor ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
S/PDIF
S/PDIF (Sony/Philips Digital Interface) is a type of digital audio interface used in consumer audio equipment to output audio over relatively short distances. The signal is transmitted over either a coaxial cable using RCA connector, RCA or BNC connector, BNC connectors, or a fibre-optic cable using TOSLINK connectors. S/PDIF interconnects components in home theaters and other digital high-fidelity systems. S/PDIF is based on the AES3 interconnect Technical standard, standard. S/PDIF can carry two channels of uncompressed PCM audio or Audio compression (data), compressed 5.1 surround sound; it cannot support lossless surround formats that require greater bandwidth (computing), bandwidth. S/PDIF is a data link layer protocol as well as a set of physical layer specifications for carrying digital audio signals over either optical or electrical cable. The name stands for Sony/Philips Digital Interconnect Format but is also known as Sony/Philips Digital Interface. Sony and Philips ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Digital Audio
Digital audio is a representation of sound recorded in, or converted into, digital signal (signal processing), digital form. In digital audio, the sound wave of the audio signal is typically encoded as numerical sampling (signal processing), samples in a continuous sequence. For example, in CD audio, samples are taken 44,100 Hertz, times per second, each with 16-bit audio bit depth, resolution. Digital audio is also the name for the entire technology of sound recording and reproduction using audio signals that have been encoded in digital form. Following significant advances in digital audio technology during the 1970s and 1980s, it gradually replaced comparison of analog and digital recording, analog audio technology in many areas of audio engineering, record production and telecommunications in the 1990s and 2000s. In a digital audio system, an analog signal, analog electrical signal representing the sound is converted with an analog-to-digital converter (ADC) into a digital ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ethernet
Ethernet ( ) is a family of wired computer networking technologies commonly used in local area networks (LAN), metropolitan area networks (MAN) and wide area networks (WAN). It was commercially introduced in 1980 and first standardized in 1983 as IEEE 802.3. Ethernet has since been refined to support higher bit rates, a greater number of nodes, and longer link distances, but retains much backward compatibility. Over time, Ethernet has largely replaced competing wired LAN technologies such as Token Ring, FDDI and ARCNET. The original 10BASE5 Ethernet uses a thick coaxial cable as a shared medium. This was largely superseded by 10BASE2, which used a thinner and more flexible cable that was both less expensive and easier to use. More modern Ethernet variants use Ethernet over twisted pair, twisted pair and fiber optic links in conjunction with Network switch, switches. Over the course of its history, Ethernet data transfer rates have been increased from the original to the lates ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Radio Transmitter
In electronics and telecommunications, a radio transmitter or just transmitter (often abbreviated as XMTR or TX in technical documents) is an electronic device which produces radio waves with an antenna with the purpose of signal transmission to a radio receiver. The transmitter itself generates a radio frequency alternating current, which is applied to the antenna. When excited by this alternating current, the antenna radiates radio waves. Transmitters are necessary component parts of all electronic devices that communicate by radio, such as radio (audio) and television broadcasting stations, cell phones, walkie-talkies, wireless computer networks, Bluetooth enabled devices, garage door openers, two-way radios in aircraft, ships, spacecraft, radar sets and navigational beacons. The term ''transmitter'' is usually limited to equipment that generates radio waves for communication purposes; or radiolocation, such as radar and navigational transmitters. Generators of radio ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
