Originally Posted by: michelvr 
Good Morning,
I have a Swiss Federal Railways (SBB/CFF/FFS) class Re 4/4 I electric locomotive and a Swiss Federal Railways (SBB) class Re 6/6 f electric locomotive and I would like to have them run together as one unit. I can not find any instructions on how to run two engines together as one on the mobile station 2. Is this possible or do I need to use a central station? Michel
Hello Michel,
Without knowing, but assuming you have two Marklin Loks and, lets say one of them is MFX, and the other is FX or a dipswitch (6090) decoder. Set the other Lok to the same address as the MFX one and it should work

(I actually haven't tried that)
If they are both same type of decoders, you don't have a problem, just set them to the same address, unless

they are both MFX
If MFX or not, try it with two MS2s, a better option if you don't have the skills and equipment to ensure a performance match between the the two.
The other option is buy a CS1-R or CS2 or Ecos, and the controller will consist them, but..

for extended running you need to ensure their performance characteristics, acceleration and braking delay and max speed are matched reasonably closely, otherwise the drive trains (gears and stuff) will wear excesively, and the Loks could even derail on curves, points etc.
Simplist option for you is two MS2's, but try running the the two Loks on the track close together to see how they compare, note the controller settings for each and then couple them together, and off you go
There are plenty of ex starter set MS2's for sale on ebay
Edit; after reading all posts;
Two MS2s, is your best ( least expensive) option, especially, if you don't have the skills and equipment to ensure a performance match between the the two.
The other option is buy a CS1-R or CS2 or Ecos, and the controller will consist them, but..

for extended running you need to ensure their performance characteristics, acceleration and braking delay and max speed are matched reasonably closely, otherwise the drive trains (gears and stuff) will wear excesively, and the Loks could even derail on curves, points etc.
Simplist option for you is two MS2's, or as Tom said disable MFX on the controller (MS2) but try running the the two Loks on the track close together to see how they compare, note the controller settings for each and then couple them together, and off you go
As Tom said a fiddle with CV's will help match them, but I suggest you work on the MFX one and if you get lost or in deep DoDo, just do a factory reset on that one

and start again. Take your other Loks off the track whilst your editing or set up a track for programming
There are plenty of ex starter set MS2's for sale on ebay