Understanding Options

@Deuce5150  There is a whole lot of info on this in the forum. I have the full DCS system and a Lionel Base I use to run TMCC engines through the MTH app. Works fine.  Both use 18 volt constant track voltage, but use different command methods which do not interfere with each other.

However with what you are planning, you would need to use the MTH controls you mentioned for MTH engines and the Cab1 for the TMCC - those would not be interchangeable.

The only squirrely thing about the Remote Commander is the MTH engines must be at the factory default. If not, the engines will not respond to signals. You will need the DCS Commander or the full blown DCS system to factory reset. And the Remote will only control PS2 and PS3 engines.

Look up the now closed topic DCS System vs DCS Commander.  In it @gunrunnerjohn said "the commander is limited as to it's power handling capability, I believe about 100 watts, the manual says 6A max. It's limited to 10 locomotives stored. Finally, the commander puts out DC to the track, regardless of the input power. Obviously, this precludes running any locomotive that depends on AC with the PS/2-PS/3 locomotives on the track. Also, the 6A will limit you to a couple of locomotives running at the same time."

Now for the good news gunrunner on another post said "Just connect the output posts (of the remote commander)  to your track, don't connect any power supply to the round power connector. This is "passive" mode for the unit. When you advance the power to the 16-18 volts used for command/control, the light on the receiver will come on, you're ready to control the train."

Hope this helps.

Hmmmm.  Looks tike the remote commander or full DCS are my best bets.  If I understand correctly, the remote commander can only control one train at a time?  if I have two or three MTH locomotives on the layout with it powered up, will all three respond to commands from the remote simultaneously?  I'm assuming so since they would all have to be factory reset to "1".  Is there a super secret workaround?

Also, for the full DCS, will I still be able to use my TMCC remotes to control the Lionel trains?  I have two boys who are eager to ring bells and blow whistles.  Can I have my phone up using the DCS while they each have a Cab1 remote in hand?

@ScoutingDad posted:

Now for the good news gunrunner on another post said "Just connect the output posts (of theremote commander)  to your track, don't connect any power supply to the round power connector. This is "passive" mode for the unit. When you advance the power to the 16-18 volts used for command/control, the light on the receiver will come on, you're ready to control the train."

Hope this helps.

Actually, that advice pertains to the DCS Remote Commander.