The short answer is no.
The 6016 is designed for two rail DC, a program that was short lived in the Marklin Digital line up.

Yes, AFAIK the polarity of the shortcut detection line is reversed.
Therefore you cannot use a 6016 directly with a 6021.

A 6016 can boost both DCC and MM (and probably mfx, too, but w/o feedback). But you have to make a connection of your own (probably w/o connecting the shortcut detection line).

Both the 6015 and 6017 will work together.
The connector for the data cable is upside down on the 6015 when compared to the 6017. There are minor differences between the two models, but will work together. Each section which is powered by a different booster needs to be isolated.

For the power supply, the polarity needs to be the same for all power supplies. This should be determined before connecting the power supplies to the layout. Once the polarity is determined, it would be a good idea to then plug all the power supplies into a power bar and just turn the power bar on and off.

Near the end of the following document created by Timothy Eckert explains how to check if the transformers are the correct polarity. http://www.marklincafe.com/MCF/...MarklinWiringBooklet.pdf

Hi Tex,

as the boosters supply digital power to the tracks (two insulated circuits!), in my opinion the polarity of the transformers feeding the boosters is not important.
What Maxi is referring to has to be applied to the tracks circuits operated in AC (analog).
I have checked the 6017 booster manual and there is no information about the polarity of the transformers (of course the "O" brown wires of the boosters must be connected together).

Bye

Renato