OK, things are beginning to take shape in my layout planning, but I have some questions concerning power. 1) I've taken a gander at that new DCC technology but for the moment it is way out of my price range so for now I will be dealing with the ol' standard transformer that comes with most train sets. My question is, how much track can this thing power before another unit or a booster would need to be added? 2) I want to run multiple trains (not necessarily at the same time) on my layout. For example, one consist travelling the circuit and maybe three or four others waiting at stations, the industrial yard, or whatever. How can I make it so that the main line has power while not affecting these other units until I want it to? I've given thought to having seperate transformers for these areas but not sure how it would work or how to seperate them from the main line while still allowing the train to enter the main line. Any ideas?