Thanks for your answers.
I have three loops of track, train on each track. I only, at present, have two controllers, both Z500s. I have the bricks that came with them, but also a Z1000 brick --but that controller is broken. So, I have been connecting two tracks to one of the controllers and using the z1000 brick and running subways in auto mode. I won't do that anymore: I'll use the z500s. My local hobby shop has a z750, so I'll buy that so I have three controllers if I want to run three subways.
And yes--I don't have a full DCS set up. When I run regular, non subway trains, I use the DCS explorer that came with a starter kit, or the old infra red hand controller so I can trigger the PSA.
I found the above mentioned controller with purple lettering on ebay, but it says it's only rated for the z500 or z750 bricks. I can't find just the controller for the z1000 brick, so it looks like I'm out of luck on that. I may use it to power an accessory or two, when I set them up.
I could buy the z4000, but it seems overkill. I have a very small layout that is basically table top loops. I change it up from time to time. The loops are really not big enough for more than a train per loop at a time, so the smaller controllers can handle the load.
Thanks for your help.
