75 ohm coaxial cable, English abbreviation SYV, often have 75-7, 75-5, 75-3, 75-1 and other models, the characteristic impedance is 75 ohms to adapt to different transmission distances. It is the main medium for transmitting video signals in asymmetric base band mode. Mainly used in SYV cables, S refers to coaxial RF cable, Y refers to the insulation material is polyethylene, V refers to the outer sheath material is polyvinyl chloride, 75 refers to the characteristic main resistance 7, 5, 3 or 1 refers to the outer diameter of the core insulation, and the last 1 and 2 indicate the structure number.

75 ohm coaxial cable is commonly used in major applications such as: device bracket connection, closed circuit television (CCTV), shared antenna system (MATV), and color or monochrome RF monitor transmission. These applications do not require the selection of precision video coaxial cables with particularly tight electrical tolerances. The characteristic resistance of the video coaxial cable is 75 ohms, and this value is not randomly selected. Physics proves that the attenuation characteristic of optimal video signal occurs at 77 ohms. In low-power applications, the material and design determine the optimal impedance of the cable at 75 ohms.