There was once a time when coaxial cables were the king of the cable world. Even now, as other cable types have become the standard, coaxial cables are still used by telephone companies, cable operators, and internet providers to transfer video, data, and voice communications.
If you are a bit older, there is a decent chance that you know what a coaxial cable is. If not, consider this your guide to coax cables, how they work, what they work for, and more.
What is a Coaxial Cable?
Before you can really get into it, it helps to know what a coaxial cable is. These are cables that have an inner conductor – or a pin – that is surrounded by an insulated layer, which is surrounded by an outer conductor or conductive shielding, and finally a protective outer jacket.
The signal flows through the center pin or conductor, transmitting information to the device it is screwed into. For a long time – and even still today – cable companies, internet providers, and communications companies all made use of coaxial cables. As it turns out, this is a simple to use yet versatile cable that still holds great use.
The Composition of a Coaxial Cable
Center conductor. Made of copper-clad steel, this is how data is transferred through the cable from device to device. There is also a center conductor bond, which uses a clean stripping polymer to block any potential moisture migration.
Dielectric. Typically made of polyethylene, this is a closed-cell foam that has a high VP which provides greater mechanical stability.
Outer conductors. There is the first outer conductor, made of an aluminum-polymer-aluminum tape. The tape is what securely bonds to the dielectric. The second outer layer is usually a 34 or 36 AWG aluminum braid. There is the third outer conductor. Also made of aluminum-polymer-aluminum tape, it can be used in both tri- and quad-shield constructions with the goal of enhancing HF shield isolation both before and after flexure. Finally, there is the fourth and optional outer conductor. The aforementioned braid is used for quad-shield constructions to improve LF shield isolation in areas where there is extreme RF noise.
Indoor and Aerial. There is a non-drip material that has been design to prevent corrosion, particularly of the metallic components of the cable. There is the underground option, which is a flowing compound that can prevent moisture mitigation. Finally, there is a corrosion-resistant protectant as well.
Jacket. There is an outer jacket made of a flame retardant polyvinyl chloride (PVC) or polyethylene (PE) to protect the cable’s core.
Integral messenger. Galvanized carbon steel wire that is attached to the cable through the use of a separate web.
Why to Use a Coax Cable
There is something of a debate as to whether to use fiber optic or coaxial cable. Coax cables are great because they are highly durable and quite easy to install. They are also quite a bit cheaper to use than fiber optic cables, which can be quite expensive depending on the application.
Coax is best used for multi-dwelling units or professional networks, typically found in apartment complexes, universities, or business campuses. Even for a work-from-home installation or data transfer network, a coax cable would be the best way to go. Though fiber is going to last longer and provide a better signal transfer quality, coax is a perfectly suitable option in most instances.