Coax is a common abbreviation for coaxial cable, a type of electrical cable that transmits high-frequency signals through a central conductor surrounded by insulation, shielding, and an outer jacket.
Coaxial cable, often referred to simply as coax, is designed to maintain consistent electrical characteristics and signal integrity across long distances. The term “coaxial” comes from the shared geometric axis of its internal components: a central conductor, dielectric insulation, metallic shielding, and an outer protective jacket. This layered construction helps reduce electromagnetic interference (EMI) and radio frequency interference (RFI), making coax ideal for precise signal transmission.
Coax cables are used extensively in commercial and industrial applications that require reliable transmission of video, radio frequency (RF), and data signals. Common examples include security camera systems (CCTV), broadcast communication systems, CATV networks, and AV installations. The cable’s shielding, often made of braided copper, aluminum, or foil, acts as a barrier to external noise, while the dielectric material ensures proper spacing and impedance control between the conductor and shield.
Different types of coaxial cables, such as RG59, RG6, and RG11, are used depending on frequency range, signal distance, and environmental requirements. Their impedance, typically 50 or 75 ohms, determines compatibility with specific systems. In industrial and AV environments, coax is favored for its durability, low signal loss, and high bandwidth capabilities, especially where consistent signal quality is critical.
Commonly regulated under NEC (National Electrical Code) and UL (Underwriters Laboratories) guidelines, with specifications defining flame ratings, shielding performance, and construction requirements for safe and reliable signal transmission.
Coaxial cable was first patented in the late 19th century but gained widespread use in the mid-20th century with the expansion of telecommunications, radio, and television broadcasting. Over time, advancements in shielding and dielectric materials made coaxial designs more robust and adaptable for industrial and digital communication systems.