Sorry to start another thread, but I've got a lot of questions. I used to search function, but all I find was stuff I didn't really understand. I'm modeling the moderen era in the Northwest so a lot or Amtrak, UP, & BNSF. I need to know how to run multiple units. The first thing I thought of was just buying dummy engines, but then on long trains going up a grade, I'd be done for. So can someone explain what I'll need. I'll basicly be buying most of my engines from Athearn, so I don't know if that helps at all, but a lil more info to help me. Thanks guys.