Should You Be Concerned With Dielectric Residue On The Center Conductor?

ChrisGemme2 Chris Gemme April 4, 2013

As you know, CommScope has an excellent reputation for manufacturing quality cables for our customers. We are also known for our outstanding customer service. Recently, we received some queries about leaving dielectric residue on a center conductor. So, I’d like to use this blog posting to address any concerns you may be having.

For all 75 Ohm coaxial drop cables, the interface inside any F-port is designed around a center contact—an air dielectric inside the port and an outer contact port face. This requires a direct contact for the center conductor to the center contact to maintain the designed impedance to match the port.

If dielectric residue is left on the center conductor, thus breaking anyphysical connection between the center conductor and the center contact, then the signal passing through the dielectric to the center contact will be slowed. The signal radiating from the end of the center conductor will arrive faster to the center contact as an antenna transmission. This difference in signal transfer will create phase delays, negatively affecting any signal performance.

Even a “tail” of dielectric can be problematic. The Society of Cable Telecommunications Engineers (SCTE) acknowledges this issue. That’s why during the SCTE Cable Games, the SCTE requires that the maximum of dielectric residue allowed on the base of the exposed center conductor can only be less than 1/16 of an inch.

Lucky for you, CommScope has optimized the dielectric material and bond in our cables so that this does not happen. Using a CommScope cable ensures that a clean prep will:

• reduce service calls and truck rolls
• ensure more efficient and productive installations
• offer subscribers a better experience

I hope this quick tip will help you eliminate any issues you may have with dielectric residue. If you have any other issues you’d like to discuss in a further blog, please use the comment section below.

About the Author


Chris Gemme

Chris Gemme is Regional PLM for CommScope, a global leader in communications networks and infrastructure solutions. Gemme has more than 20 years’ experience in telecommunications. Prior to his current role, he served as director field applications engineering and as product manager of coaxial cables. Before joining CommScope, he worked at Time Warner Cable. Gemme earned his bachelor of science degree from Troy State University and his MBA from Regis University. Gemme is a member of the Society of Cable Telecommunications Engineers (SCTE). He has also served on the SCTE Engineering Committee, which is responsible for all standards and recommended practices activities of the Society.