Audio/Video question

[Not Kuno]

A part of my TV broke a while ago. Instead of having 2 A/V places, I only have 1, used for my satellite thing. I didn't really care that it broke because the satellite has 2 A/V input spots in the back for any systems I'd want to play. But the problem is whenever I try to play an old system it refuses to show anything. I couldn't understand it and it pisses me off as the A/V is hard to reach behind the TV and manually changing it often is annoying. So I have a few questions.

1) Why does this happen? I just dont understand why it refuses to show old systems. The sound works fine. I never had this problem with ps2 until I put in a ps1 game and it does the same thing. -.- Is there any way to remedy this or am I just SOL with this satellite thing.
2) Anything I can do about it? I thought about getting one of those multi A/V things my friend has but I have no idea how much they cost or what they're called.

[Furtwangler]

Idk why, but run your satelite and your games through this(or something similar, can get em cheap at radioshack) into your tv, will fix it
http://www.amazon.com/Port-Selector-...2903950&sr=1-2