Guide to Coaxial Cables

Standard coaxial cables are electrical networking cables that consist of four layers: a round conducting wire, an insulating material, a cylindrical conducting sheath, and an outer insulating layer. Serving as high-frequency transmission lines, they carry high frequencies or signals from a source to a receiver.

Coaxial cables have many applications. Short coaxial cables are commonly used in home audio and video equipment connection, electronic measurement, and computer networking. Long-distance coaxial cables, on the other hand, are used in television and radio network connections to carry cable signals. Coaxial cables are also used in ultrasound scanning and military applications.

Shielding types

Standard coaxial cables

Standard coaxial cables are designed with an inner conductor surrounded by a dielectric. The dielectric is contained in an outer conductor that also serves as a shield to protect the cables from dirt, dust, and damage. A protective jacket that acts as an insulator covers the outer conductor. Most types use aluminum Mylar tape as barrier shields. They are available in different colors.

Dual-shielded coaxial cables

Dual-shielded coaxial cables feature two shields or outer conductors that enclose the dielectric. They provide added strength and protection against abrasions. Their dual shielding also helps decrease attenuation and unwanted external signals. Most models use aluminum Mylar tape as barrier shields. They are available in different colors.

Triaxial cables

Triaxial cables, also called triax, have a third layer of shielding, sheathing, and insulation. They consist of one conductor inside and two outer shields separated by the dielectric.  The third layer is often earthed or grounded to protect the inner shields from electromagnetic interferences coming from outside sources. They create signals that can be transported by the inner shield or the inner conductor, while the outer shield remains grounded. Some models use aluminum Mylar tape as barrier shields.

Cable types

Twin-axial cables

Twin-axial cables, also called twinax, are balanced, twisted pairs enclosed in cylindrical shields. The twisted pair of insulated conductor cables has a common shielding and protective jacket. Most models use aluminum Mylar tape as barrier shields. They are available in different colors.

Biaxial cables

Biaxial cables, also called biax, consist of two coaxial cables designed with a figure-8 configuration. They are commonly used in propriety computer networks. Some models use aluminum Mylar tape as barrier shields.

Multi-conductor coaxial cables

Multi-conductor coaxial cables consist of several coaxial and twin-axial cables. Their total number depends on the user’s specifications. They are shielded with jackets made of various materials and colors. Some models use aluminum Mylar tape as barrier shields.

Rigidity types

Rigid coaxial cables

Rigid coaxial cables, also known as hard line cables, have solid sheaths usually made of steel or other durable metals. They are thick, usually measuring a diameter of one-half inch. They offer excellent screening and protection, but are not flexible. They are commonly used to connect ground transmitters to aerial antennae in radio communications and other broadcasting applications.

Semi-rigid coaxial cables

Semi-rigid coaxial cables have outer sheaths made of solid copper. They offer greater screening at higher frequencies than cables with braided outer conductors. They are not flexible because of their semi-rigid properties. They do not allow flexing after initial forming.

Flexible coaxial cables

Flexible coaxial cables have braided outer sheaths made of thin copper wire. They can easily flex and bend. They do not offer maximum protection and screening. 

Impedance: For industrial CCTV, choose a coaxial cable with an impedance of 75 Ohm that allows the emission of balanced video and composite video signals. It also works well with all types of CCTV cameras, monitors, amplifiers, multiplexers, switchers, and time-lapse recorders.

Efficiency: For efficiency, choose a coaxial cable shielded with a 100% copper material and a center core stranded or braided with a 100% solid material.

Jacket: Look for a coaxial cable that comes with a durable jacket for exceptional protection against unwanted electrical signals and grounding. 

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