Before under taking any work with electrical equipment be sure to isolate all of it from the mains supply.
If your equipment makes it available R.G.B is best but not all equipment manufactures equip their recent products to I-P via Skart quite often you may find your to choose from either H.D.M.I or PHONO composite (colour code is yellow = video, red = audio right , white = audio left) also some Televisions may also have a component input using same connections for the audio but with three extra connectors of the same style as the yellow one but these sockets will be colour coded red green and blue and if this is the case you may need to select either Component or composite via a set up menu option. you need a cable with 5 phono lines to utilise the component input (or a combination adding up to five. These colours make it easy to match up cable ends to respective socket but electrons don't care what colour code the terminals are. If you make up a lead comprising a set of leads coded yellow red and white set of phono and a skart to phono adaptor which may often be included with video recording equipment (you could have one tucked away somewhere) So connect one end of the phono lead to the skart adaptor. Connect the remaining phono connectors to the corresponding sockets on the Television the skart end going to your set top box. Hope that helps
Graham Lewendon : I am rather curious as to why you have referred to my user ID in the leading line of your posting, as I cant recall in recent times of having ever replied to such a question, therefore maybe you could be so good as to enlighten me on what you are specifically referring to in order to save me having to delve into the archives of previous replies that I may possibly have made, which judging by the heading would suggest as being connected with RF modulators.