Coaxial cable has been around since the late 19th century. It is the medium that made the cable industry possible. In the 150 years since the invention of coax, our industry has changed markedly, with most new networks being built using fiber optic technology. Among the commonalities of these networks is the fact that each one of them is only as good as its weakest connection.
Given the long history of coaxial cable, one would think that the connectors used in our networks have long since been perfected. Instead, new materials and technology continue to improve these critical connectors, improving install-ability along with their performance over time.
Most hardline connectors used in coaxial cable networks are made from aluminum. These connectors have the benefit of being lightweight, but the metal has a lower density, and therefore strength, when compared to an alternative such as brass. Measured in megapascals (MPa), aluminum’s tensile strength ranges from 70 to 700 MPa depending on the alloy. Brass, an alloy of copper and zinc, has a higher tensile strength, ranging from 200 to 900 MPa.
Additional benefits of brass include:
- Does not experience galling, which is an adhesive wear on sliding metallic surfaces often referred to as “cold weld.”
- Disassembly of the connector is clean, without introduction of metal into the cable.
- Even after over-torquing, operational threads are maintained.
- Internal threads of the housing are less likely to be damaged when side-loading occurs.
In short, while aluminum is suitable for applications where weight is a critical factor, brass offers greater strength and hardness, making it preferable for applications requiring durability and repeatability over time.
Of course, the material from which it is made is only one factor in the selection of a good hardline connector. There are many others.
The pulling of the center conductor away from the connector, a phenomenon known as “suck-out” or “pull-out,” can result in deterioration or even loss of signal. The most advanced hardline connectors address this using an advanced polymer activator system along with a multigrip seizing mechanism. Such an approach uses a helix connection wherein the seizing mechanism clamps on the center conductor like a screw. Contact is made in a helix around the center conductor rather than in just the circular way typical of older technology connectors. The helix also makes contact farther back on the center conductor, greatly increasing its overall grip. With 1.8 GHz bandwidth getting closer as a standard this feature allows for signals to pass along the conductor seamlessly.
The most advanced connectors on the market will be easy to install and maintain. Look for connectors that prevent the coaxial cable from turning during installation. Equally important is a connector that applies uniform grip and correct pressure to the cable’s center conductor as it is tightened, greatly reducing the risk of intermodulation distortion.
With less and less square footage dedicated to more and more varied equipment deployments, it seems that tight or difficult installation sites are becoming the norm. A connector with a full mechanical stop, and no need for a bulky torque wrench, facilitates an easier installation. Additionally, greater repeatability due to these features will ensure that craftspeople will achieve a higher skill level more quickly when working with the new technology.
In summary, although the migration to fiber optics as the chosen technology for broadband service marches on, hardline coax will continue to serve millions of consumers for a long time to come. Therefore, it is critical that broadband service providers, and manufacturers, continue to improve the performance of every piece of their network, including the adaptation of the latest technology for hardline connectors.
Marion Nowosatko
Training Manager,
Amphenol Broadband Solutions
Marion Louis Nowosatko Jr. is a Training Manager at ABS. He is a distinguished professional known for his expertise and contributions in the broadband industry. His demonstrated leadership and technical acumen have had significant impact over a decades-long career, making him a valued mentor and key figure in the development of innovative solutions. An Army veteran and father of two, Marion resides in Denver with his wife.
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