MTH Railking SD70ACe Imperial Diesel w/protosound 3.0 Wabash

The MTH control system is DCS. That will give you access to the full features of Proto-3 engines. DCS will peacefully coexist with Lionel TMCC/Legacy because the commands are sent with a digital signal on the track voltage, where TMCC/Legacy uses the track as a radio antenna.

As for conventional operation, most of the newer transformers will work with the Proto-3 engine and MTH includes a list in the user manual on the engine. You can operate the horn, bell, couplers, and some other features using combinations of horn and bell button pushes (you have to practice). Some of the newer locomotives have the full manual (which goes into more detail) available for download as opposed to being in the box with the locomotive.

 AGHRMatt - THANKS For providing me with this info which gives me another option.  I'm finalizing the purchase of Fastracks, which will give me all of the tracks (I hope) for my layout which is a combination of 2 Fastrack layouts from the Fastrack Layout book.  On this layout are curves which cover O-36 to O-72.  I've tried to purchase trains so far that will be able to handle O-36 on up because I don't want to encompass derailments (theoretically) while in the planning stage.  I already have slated for purchase the Chicago Alton Limited passenger cars which have an O-54 minimum curve requirement and I don't want to compile additional trains that might derail because a good portion of my layout has smaller radius track, so when you provide the info on the MTH DCS, and MTH makes the same diesel loco that I need with a radius that I my layout can handle (theoretically of course), it takes away that problem for now and I did want to purchase the MTH DCS controller down the road anyway.  Thanks again for your advice.

You're welcome. Best bet is to take the initial pain of purchasing a TIU & Remote together. It's a one-time expense. Also, when wiring your layout, the general rule of thumb is to section it out into blocks and have each block fed from ONE and only ONE power feed (keep them short) which leads back to a terminal block. Each block should be insulated from its neighbors (at least on the "hot" rail. When DCS is installed, this will prevent signal feedback from happening and provide better operation. The TMCC/Legacy connection should be to the common connection on the transformer which will ensure the TMCC signal gets to the entire layout.

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