rhikdavis

Originally Posted by WP&P

I'm sure you'll hear from some DCC enthusiasts that it will probably be simpler overall to go that route; you just feed power to the rails, without worrying about switching certain segments on or off. You can get a decent starter DCC controller and engines with decoders already installed, so as far as setup goes the only extra step might be programming (i.e. configuring the controller to recognize the engine).

I'm not a DCC guy; I'm Old Skool, using toggle switches to assign discrete track sections to one of several analog controllers, or off. The biggest thing about this control method is that you need to carefully plan out where your electrical blocks will be. You need to think of where you are likely to have two locomotives operating independently, and insert block boundaries between them. A block boundary can be an insulated rail joiner, i.e. plastic joiner rather than metal, or it can be a gap that you cut into the rail using a rotary tool or fine saw, that you then fill with styrene or some other insulating material to prevent the gap closing back up.

Once you've got blocks isolated, you need to feed power to each one. The power feed to a given block needs to come off of a toggle switch, and it's the toggle switch (usually a DPDT with center-off function) that lets you do what you're talking about. A DPDT has six prongs to it; you'd connect the block feeders to the center two prongs, and then you'd connect Cab A's output to two prongs on one end, and Cab B's output to the other two prongs. Center-Off means that you can leave the toggle "un-thrown", i.e. with the knob in the center and not connecting to either Cab. If you only have one cab, and don't intend to add another, then you can use Single-Throw (DPST) toggles instead - this is more like a normal light switch, either on or off. You might even use Single-Pole (SPST) toggles, which would just cut power to one of the two rails, but if you're not careful this could lead to odd happenings later on; I prefer to just go ahead and isolate both rails of every block.

Obviously, with all these toggles, you need some place to mount them, which means creating a control panel with a schematic track layout on it. This could possibly be done just on the layout edge (the fascia), perhaps with text labels at each toggle rather than a track schematic.

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