Hi Tucker,
It sounds like you are looking at a TMCC, not Legacy equipped locomotive.
TMCC is Lionel’s original/1st generation command control system, Legacy is Lionel’s second(and current) generation command control system. Legacy has finer speed control, 200 vs 128 for TMCC IIRC and has more functions than TMCC, such as the quilling whistle.
Each system will operate the other, to within the limits of the lowest common denominator. TMCC will run Legacy locomotives, but will not have access to second generation features. a Legacy locomotive will respond to the 32 or 128 speed step scale of the TMCC system, and of course directional control and basic sound controls, but wont be able to quill the whistle/horn of a legacy locomotive.
The Legacy system will operate all the features of the TMCC locomotives, but will not be able to offer the features of the Legacy locomotives, that TMCC doesn’t offer.
Legacy, TMCC and MTH’s DCS system, can all be used at the same time, and do not interfere with each other, “They Play Nicely Together”. Legacy will control TMCC locomotives, but if you have, and still want to use any TMCC “Cab1” remotes, you will need to hook up both the Legacy and TMCC bases, which the Legacy system should include the proper cable for connecting the bases together.
MTH’s DCS system is also capable of controlling Lionel command control locomotives, but it still requires that you at least have a TMCC base connected to the DCS system, as it can not control them without it.
Although Lionel no longer produces the TMCC system, it is still a viable system, and in MY EXPERIENCE, is a m uch more robust reliable system(I have BOTH systems, and locomotives with each system). I have had faillures of two Legacy locomotives, that had very little use when they failed. All of my TMCC locomotives have performed flawlessly for years witout fail. The only TMCC failure, that I have had was with the TMCC