What is a Coaxial Cable and How Is It Used?

You may have heard the term coaxial cable thrown around when talking to your local cable provider about setting up your TV or router. It’s a standard cable that connects us to the audio, video, and other data we love, and knowing how it’s used can help you connect correctly.

Also known as coax, coaxial cable is an incredibly common type of cable, and it’s used to connect audio and video systems, including radio transmitters, cable television service, and high speed internet. There are a few different types of coaxial cable, and knowing the difference between coaxial speaker cable and the type of coaxial cable used with cable television service will ensure you get the right kind for your application.

What is a coaxial cable?

No matter what type of high speed coax cable you are dealing with, they all share certain characteristics that make them coaxial cable, as opposed to some other kind. The thing that ties coax cables together as a family is the fact that the center conductor and the outer shield share the same axis.

This shared axis is accomplished by the unique construction associated with coax cables. The vast majority of coax cables include the following parts:

• Center conductor – The innermost layer of coaxial cable is the center conductor. It’s made of copper, and may be solid or stranded, and may be made of pure copper or be copper coated.
• Dielectric insulator – The center conductor is wrapped by a dielectric insulator, usually made of some type of plastic. Its main purpose is to maintain spacing between the center conductor and the shield. 
• Foil shield – Coaxial cables may or may not have this component, but it’s fairly common in many cables.
• Woven or braided shield – Made of copper or aluminum, this is an essential part of the coaxial cable structure. It shares an axis with the center conductor and shields the cable from interference, as well as prevents leakage to the outside.
• Outer jacket – The outer jacket contains and protects the other elements that make up the coaxial cable. 

While there are a number of different types of coaxial cable on the market, each type is constructed similarly and has all the same basic components as the others. Some use cases may require thicker insulation or a different gauge center conductor, but they are still all going to be constructed of those same 4 or 5 elements.

What is a coaxial cable used for?

Coaxial cables are primarily used for sending audio and video signals. In many use cases, they are integrated into complex video relay and distribution systems, and the vast majority of us will never even set eyes on them. The most common cables used in video applications are: 

• RG59/U – Mainly used to transmit HD video signals over short distances.
• RG6/U – This is the main type of coax we use to connect cable TV and internet in our homes and offices.
• RG11/U – Same as RG6/U, but thicker and suffers less signal loss. These types are great for sending signals over very long distances.

Unless we are IT professionals, most of us may not even see a whole lot of the more common types of coax out there. RG11/U cables, for example, are too thick and stiff to be easily used in the home. They are also expensive, so we are much more likely to run across RG6/U cables inside the home.

Where you’re likely to run into coax

If you aren’t a highly technical type, you will likely only run across a couple main types of coaxial cable on your property—coaxial cable for TV and coaxial speaker cable. The main visual difference between your coaxial cable for TV and coaxial speaker cable comes down to the coaxial cable connectors, so the easiest way to spot the difference is to look at those connectors, as well as what devices they may be hooked up to.

Coaxial Television and Internet Cable

The type of cable that comes to most minds when they hear the term coax thrown around is the type of coaxial cable for internet modems with the Type F connector, which has a very thin wire protruding from a barrel with threads on the inside for establishing secure connections. They’ve been around for 150 years or so and are a very reliable way of delivering data to our home devices. It’s most likely to be hooked up directly to your TV or modem.

Coaxial Speaker Cable

The other likely type of coax you may run into is the coaxial speaker cable. You can recognize this type of coax by the RCA connection at the end. It’s an audio connection you’ve likely seen over the years and resembles a type F connection but has a thicker center conductor and no threads on the inside of the barrel. RCA connections were the standard means of connecting audio components before the days of a single speaker and optical wire.

They have a few advantages over other types of speaker cables like standard speaker wire and optical cables. Still, the actual benefits of coaxial speaker cables are heard in their ability to deliver high quality audio signals while providing superior protection from interference.

How to get internet from coaxial cable

Most commonly, people use coaxial cable in their homes to deliver television and internet service. It’s been the standard for home wiring throughout the past several decades and offers a reliable way to transmit high-frequency electrical signals with low losses, free from electromagnetic interference. Chances are, your house is wired with coaxial cable for TV and internet already.

Coax vs. Fiber

If your local internet providers have installed fiber optic lines in your neighborhood, you’ve got access to the fastest internet speeds available today. Fiber optic lines are capable of carrying data significantly faster than coax, so fiber optic is the best choice if it’s available to you. 

Even if you’ve got fiber optic internet in your area, there’s a good chance that either coaxial cables, Cat5e or Cat6 ethernet cables are still carrying your high speed internet over the last mile of your connection. 

Coax vs. Ethernet

Once the fiber optic connection reaches your local network, the speeds you ultimately achieve will be dependent upon which type of cables you have running through your home.

If you’ve got Cat5e or Cat6 cables, your speeds will likely be much faster than if you have coax. If your home network is wired with coax, and you want to get the most out of your fiber optic broadband connection, some updates to your home wiring will get you better speeds.

What internet speed can coaxial cable handle?

Understanding the difference between coaxial cable for TV and coaxial speaker cable will give you a good starting point to properly connecting your equipment. Still, if you want the fastest speeds available, you’ll want an upgrade. Coax cable speeds usually top off at 100Mbps, depending upon the speeds provided at the cable’s connection. Even the best coaxial cable for high speed internet will be technologically obsolete in the next decade or so. As the world of broadband connections evolves, the only surefire way to keep your speeds up is to upgrade your connection.