RG-59/U is a specific type of

coaxial cable 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 p ...

, often used for low-power

video Video is an electronic medium for the recording, copying, playback, broadcasting, and display of moving visual media. Video was first developed for mechanical television systems, which were quickly replaced by cathode-ray tube (CRT) syste ...

and RF signal connections. The cable has a

characteristic 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 ...

of 75 ohms, and a capacitance of around 20pF/ft (60pF/m). The 75 ohm impedance matches a

dipole antenna In radio and telecommunications a dipole antenna or doublet is the simplest and most widely used class of antenna. The dipole is any one of a class of antennas producing a radiation pattern approximating that of an elementary electric dipole w ...

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 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 Depar ...

. 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 In telecommunications and signal processing, baseband is the range of frequencies occupied by a signal that has not been modulated to higher frequencies. Baseband signals typically originate from transducers, converting some other variable into a ...

video frequencies, such as

composite video Composite video is an analog video signal format that carries standard-definition video (typically at 525 lines or 625 lines) as a single channel. Video information is encoded on one channel, unlike the higher-quality S-Video (two channels) a ...

. 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 RG-6/U is a common type of coaxial cable used in a wide variety of residential and commercial applications. An RG-6/U coaxial cable has a characteristic impedance of 75 ohms. The term, ''RG-6'', is generic and is applied to a wide variety of ...

or RG-11 are used instead. In cases where the transmission distance is too long for these media, such options as UTP (

unshielded twisted pair Twisted pair cabling is a type of wiring used for communications in which two conductors of a single circuit are twisted together for the purposes of improving electromagnetic compatibility. Compared to a single conductor or an untwisted bal ...

) or

fiber optic An optical fiber, or optical fibre in Commonwealth English, is a flexible, transparent fiber made by drawing glass (silica) or plastic to a diameter slightly thicker than that of a human hair. Optical fibers are used most often as a means to ...

can be used. RG-59 coaxial cable is commonly packed with consumer equipment, such as

VCR A videocassette recorder (VCR) or video recorder is an electromechanical device that records analog audio and analog video from broadcast television or other source on a removable, magnetic tape videocassette, and can play back the recording. ...

s or digital cable/satellite receivers. Manufacturers tend to include only RG-59 cables because it costs less than

does. However, given the short lengths provided (usually ), this is generally sufficient for its typical use. RG-59 is frequently used to

synchronize Synchronization is the coordination of events to operate a system in unison. For example, the conductor of an orchestra keeps the orchestra synchronized or ''in time''. Systems that operate with all parts in synchrony are said to be synchronou ...

two

digital audio Digital audio is a representation of sound recorded in, or converted into, digital form. In digital audio, the sound wave of the audio signal is typically encoded as numerical samples in a continuous sequence. For example, in CD audio, sa ...

devices, such as

ADAT Alesis Digital Audio Tape (ADAT) is a magnetic tape format used for the recording of eight digital audio tracks onto the same S-VHS tape used by consumer VCRs. Although it is a tape-based format, the term ''ADAT'' now refers to its successo ...

optical devices. This is called

word clock In digital audio electronics, a word clock or wordclock (sometimes sample clock, which can have a broader meaning) is a clock signal used to synchronise other devices, such as digital audio tape machines and compact disc players, which interco ...

References

Bibliography

* Signal cables Transmission lines {{Electron-stub

See also

References

Bibliography