I am sure this is covered and has been many times but I have not found a good way to search the forum here and have only been reading Model Railroader for decades (focused very much on HO and N) and am new to modern O gauge.
Question/problem is I have a few post war and 70's lionel, a couple MTH conventional AC third rail and a new to me Lionel Legacy engine. I had planned on running DCC of some variety on my new layout. I have nothing in the way of controllers or transformers. Just a 75 watt lionel from 70's and an MTH 50 watt.
I would like to run all the engines on the same track or layout but it seems like the conventional AC powered lionel and MTH locos will not do this in conjunction with the Legacy system. From the user manual for Legacy they show something like a Lionel ZW 250 ish watt providing power but do not seem to specify that this would be the constant voltage terminals of the ZW. It would seem that would be the set up so that there is AC power available for what I am assuming must be the Legacy decoder in the loco.
Does anyone have recommended path forward to allow the fleet I have to be used? Probably not important but planning on a mix of Ross manual and machine switches. I also have a model railroad Dr Arduino kit but again dont see that being applied to the basic power and control scheme for engines.
It seems like the Legacy loco means that the rest of the fleet needs to have some type of decoder to be on the same layout. Yes? I would be willing to do this but it looks like it would cost a couple hundred a loco to upgrade given there is space and I could rewire the loco(s) motors and electronics (E unit?). I am fine with soldering as I do this for tiny circuits at work when needed.
Is there an advantage to DCC control on the conventional AC locos that would converted to DCC by going bluerail versus the DCC being carried by the track transmission line? Cost? Complexity of operation?
If I use the legacy and another DCC type system (I like blue rail for example) what AC power pack would be most economical and allow running 3-4 engines. I have only had time to current draw test one of my lionel 1956 switchers for current and it looked to be about 4 amps. Assume my mth modern locos may also pull this but I would expect their motors and certainly electronics are different so maybe not.
One more ignorant question, the 50 watt MTH tranformer that is hooked to my test track showed AC output. I am used to DC from HO. So these really are just transformers of voltage taking the 115v AC to about 15V AC with a reostat and current protection. The Locos like the lionel 1956 and MTH have rectifiers to change the AC to DC for the motors?