Editing Coaxial cable (section)

== Types ==

=== Hard line ===

[[File:Coaxialcableoneandfifthofan.jpg|thumb|upright|{{convert|1+5/8|in|abbr=on}} flexible line with (mostly) air dielectric]]

[[File:CDMA Cell antenna.jpg|thumb|upright|{{convert|1+5/8|in|abbr=on}} Heliax coaxial cable with FPE foamed polyethylene dielectric]]

Larger varieties of hardline may have a center conductor that is constructed from either rigid or corrugated copper tubing.  The dielectric in hard line may consist of polyethylene foam, air, or a pressurized gas such as [[nitrogen]] or desiccated air (dried air).  In gas-charged lines, hard plastics such as nylon are used as spacers to separate the inner and outer conductors.  The addition of these gases into the dielectric space reduces moisture contamination, provides a stable dielectric constant, and provides a reduced risk of internal [[Electric arc|arc]]ing.  Gas-filled hardlines are usually used on high-power [[Radio frequency|RF]] transmitters such as television or radio broadcasting, military transmitters, and high-power [[amateur radio]] applications but may also be used on some critical lower-power applications such as those in the microwave bands.  However, in the microwave region, ''[[waveguide]]'' is more often used than hard line for transmitter-to-antenna, or antenna-to-receiver applications.  The various shields used in hard line also differ; some forms use rigid tubing, or pipe, while others may use a corrugated tubing, which makes bending easier, as well as reduces kinking when the cable is bent to conform.  Smaller varieties of hard line may be used internally in some high-frequency applications, in particular in equipment within the microwave range, to reduce interference between stages of the device.

=== Radiating ===
{{Main|Leaky feeder}}
'''Radiating''' or '''leaky cable''' is another form of coaxial cable which is constructed in a similar fashion to hard line, however it is constructed with tuned slots cut into the shield. These slots are tuned to the specific RF wavelength of operation or tuned to a specific radio frequency band. This type of cable is to provide a tuned bi-directional "desired" leakage effect between transmitter and receiver. It is often used in elevator shafts, US Navy Ships, underground transportation tunnels and in other areas where an antenna is not feasible.  One example of this type of cable is Radiax ([[CommScope]]).<ref>{{cite web
| url= http://www.commscope.com/Product-Catalog/Wireless/Brand/RADIAX-/
| title= CommScope Radiax
| access-date= 2016-06-28
| archive-url= https://web.archive.org/web/20160530224242/http://www.commscope.com/Product-Catalog/Wireless/Brand/RADIAX-/
| archive-date= 2016-05-30
}}</ref>

=== RG-6 ===
{{Main|RG-6}}
'''RG-6''' is available in four different types designed for various applications.  In addition, the core may be copper clad steel (CCS) or bare solid copper (BC).  "Plain" or "house" RG-6 is designed for indoor or external house wiring. "Flooded" cable is infused with water-blocking gel for use in underground conduit or direct burial. "Messenger" may contain some waterproofing but is distinguished by the addition of a steel [[messenger wire]] along its length to carry the tension involved in an aerial drop from a utility pole.  "[[plenum cable|Plenum]]" cabling is expensive and comes with a special Teflon-based outer jacket designed for use in ventilation ducts to meet fire codes. It was developed since the plastics used as the outer jacket and inner insulation in many "Plain" or "house" cabling gives off poisonous gas when burned.

=== Triaxial cable ===
{{Main|Triaxial cable}}
'''Triaxial cable''' or '''triax''' is coaxial cable with a third layer of shielding, insulation and sheathing. The outer shield, which is earthed (grounded), protects the inner shield from electromagnetic interference from outside sources.

=== Semi-rigid ===

[[File:Semi-Rigid Coax.png|thumb|upright|Semi-rigid coax assembly]]
[[File:Semi-Rigid Coax Installed.jpg|thumb|upright|Semi-rigid coax installed in an [[Agilent]] N9344C 20GHz spectrum analyser]]
'''Semi-rigid''' cable is a coaxial form using a solid copper outer sheath. This type of coax offers superior screening compared to cables with a braided outer conductor, especially at higher frequencies. The major disadvantage is that the cable, as its name implies, is not very flexible, and is not intended to be flexed after initial forming. (See {{slink || Hard line}})

Conformable cable is a flexible reformable alternative to semi-rigid coaxial cable used where flexibility is required. Conformable cable can be stripped and formed by hand without the need for specialized tools, similar to standard coaxial cable.

=== Rigid line ===

'''Rigid line''' is a coaxial line formed by two copper tubes maintained concentric every other meter using PTFE-supports. Rigid lines cannot be bent, so they often need elbows. Interconnection with rigid line is done with an inner bullet/inner support and a flange or connection kit. Typically, rigid lines are connected using standardised [[EIA RF Connectors]] whose bullet and flange sizes match the standard line diameters. For each outer diameter, either 75 or 50&nbsp;ohm inner tubes can be obtained.
Rigid line is commonly used indoors for interconnection between high-power transmitters and other RF-components, but more rugged rigid line with weatherproof flanges is used outdoors on antenna masts, etc. In the interests of saving weight and costs, on masts and similar structures the outer line is often aluminium, and special care must be taken to prevent corrosion.
With a flange connector, it is also possible to go from rigid line to hard line. Many broadcasting antennas and antenna splitters use the flanged rigid line interface even when connecting to flexible coaxial cables and hard line.
Rigid line is produced in a number of different sizes:

{| class="wikitable"
|-
! rowspan=2 | Size
! colspan=2 | Outer conductor
! colspan=2 | Inner conductor
|-
! Outer diameter (not flanged) !! Inner diameter !! Outer diameter !! Inner diameter
|-
| 7/8" || 22.2&nbsp;mm || 20&nbsp;mm || 8.7&nbsp;mm || 7.4&nbsp;mm
|-
| 1 5/8" || 41.3&nbsp;mm || 38.8&nbsp;mm || 16.9&nbsp;mm || 15.0&nbsp;mm
|-
| 3 1/8" || 79.4&nbsp;mm || 76.9&nbsp;mm || 33.4&nbsp;mm || 31.3&nbsp;mm
|-
| 4 1/2" || 106&nbsp;mm || 103&nbsp;mm || 44.8&nbsp;mm || 42.8&nbsp;mm
|-
| 6 1/8" || 155.6&nbsp;mm || 151.9&nbsp;mm || 66.0&nbsp;mm || 64.0&nbsp;mm
|}