A wall wart is a generic name for a tranformer that plugs into the wall and supplies power. 12 V is common, but computer power sources are much higher. It's an inexpensive power source available from Amazon or Ebay.
gthomson
The one connector is power to the overhead and track and the other is to the FROG switches
You just threw us a BIG monkey wrench. All turnouts have frogs. The frog is the little wedgie shaped thing where the rails diverge. Frog power isn't A or B, but changes from A to B when the switch (turnout) is thrown. Therefore it is never a constant.
There is something called a Frog Juicer, which is a DCC reverser, and figures out which polarity the frog needs right here and right now. We don't know that you have one of those, but it could be powered by a wall wart and it would "know" what needs to happen down stream.
DCC reversers aren't compatible with DC systems. So there is no equivalent of a Frog Juicer for DC.
There are DC switch machines, like RIX which can power the frog. 25 years ago I powered the turnout with a momentary switch, but I don't remember how I did it.
Atlas can power the frogs too, but I'm not the one to explain that. For sure, the power from the transformer doesn't go directly to the frogs.
I apologize for not knowing what a Robertson bit or screw is, I'm ignant. (sp)