repairing a coaxial cable?

the reception on my digital tv is terrible

by wiggling etc the coaxial cable in the back of the receiver it is 100% ok for a few seconds or even minutes

i want to restrip the end of the cable - but dont know the significance of the brassy coloured wire which forms one of the layers

are there any pictures or clear instructions available on what i am sure is straightforward

thanx

paul wilkinson
January 2007