Thanks for your answers  .  I have noticed that my DCC equipped locomotives run a lot better on DCC than on DC.  One locomotive in fact, runs poorly on DC, but on DCC is runs excellent.

I just got an E-Z command controller for Christmas. I want to  be able to run my older DC trains with my DCC equipped ones.  The manual says that it recommends the #44212 controller for the required DC controller. I have a #46605A controller which appears to be very similar. Will my current DC controller work? 

Also, according to the instruction manual's pictures and wiring diagrams when the E-Z command controller and DC controller hooked together is appears that the only power source for the entire system is the power pack connected to the DC controller, and no power pack is connected directly to the E-Z command controller.  Is this correct?

Sorry if my questions are stupid, this is the first time that I have used DCC.

Merry Christmas (and Happy Festivus lol)

Ok thanks for the advice

I own a Spectrum F40PH locamotive.  The first one kept on constantly derailing so I had to exchange it.  The second one I got still sometimes derails allthough rarely and can sometimes operate a little roughtly (doesn't always maintain a constant speed.  My other trains seem to work fine on the same track.  Any suggestions?