I'd like to hang coaxial cable parallel to and about 2 inches away from a lighting fixture cable, from the ceiling to the floor (about 8 feet). I have to take off the wall plate to get a better idea whether the lighting fixture cable runs vertically, but I live in a tall building so I think it does. There's an uglier way I could route the coaxial cable (around a bedroom doorway) and a longer way (through two closets and along two walls) but I'd rather not. Could I just use any quad shield and not worry?
This has some good information. In the Shield Effectiveness table, 6 levels of RG6 shielding are listed, and quad shield is the best. I'll just use whatever quad shield I could find. I'll only need 8-10 feet.