Coaxial (coax) cables are used in video equipment, computer networks and cable TV. Coax cables are used to run data from your television, and they also serve as a transmission line for radio frequencies like that of VHF radio transmitters. A coax cable has two conductors that share a common axis. The inner conductor is a solid or stranded straight wire. The outer conductor is a shield that often consists of a foil or braided wires.
Twin-axial cables have two inner conductor wires and are often used for computer network setup. IBM's AS/400 computer system and other mid-range systems use twin-axial cables.
The tri-axial cable has an extra layer or an outer jacket that covers an outer braid. This type of coax cable is used to prevent data loss and is used frequently in the broadcast Industry. It transmits video signals as well as service signals.
Semi-rigid Coaxial Cable
This type of coax cable is less versatile and less flexible. The semi-rigid cable comes with a harder shielding metal, which is perfect for microwave transmission.
RG6 Coaxial Cable
This type of coax cable was designed by and used in the military. RG means "Radio Guide," and the numbers are design designations. In recent years, RG coax cables have replaced the RG 59 series in most applications because of their durability and cost effectiveness. They are also used in the cable television industry. They have an 18 AWG (American Wire Gauge) center and 75 ohms impedance.
Hard Line Coaxial Cable
The hard line coaxial cable is the most heavy-duty coax cable. The outer shielding is a rigid or semi-rigid pipe. It does not consist of braided or flexible wire. The spaces between the inner and outer conductors have nylon or tough solid plastic separating them. The hard line coaxial cable is very thick and is used for radio transmitters requiring high signal strength.