Component video cables are round 75 ohm coaxial cables also. What counts is the proper kind of plugs (usually RCA, once in awhile BNC) on the ends and also sufficient bandwidth for the video signal, suggested three times 37 MHz for HDTV, 3 times 13 MHz for progressive scan. The coaxial cable used for antenna and cable box runs actually has a higher bandwidth.
Unfortunately there is sometimes no easy way to figure out the bandwidth of the cable, sometimes labeled "premium grade" or "gold plated contacts" or (nothing special). You cannot tell the grade by looking at the outside since part of the quality depends on the material that holds the center conductor centered (concentric; coaxial) within the braided shield conductor inside.
Video hints:
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