Re: agenda item: DCS purchase

["Ira Schneider" <ira_schneider@iname.com>]

There should not be a signal problem for TMCC engines when running on a TIU controlled track.

The standard setup, as defined in the DCS Users' Manual, includes a ground wire between
the Lionel Command Base and the TIU.  (This is probably not needed in our layout since all
of our tracks have the outer rails connected together.)  I believe this wire is intended to
carry the TMCC signal from the Command Base to the outer rail of the track controlled by the TIU,
allowing the CAB-1 to control a TMCC engine running on that track.

As a matter of fact, even if we connect the Command Base-TIU cable and use the MTH controller
for TMCC engines, the Command Base is still sending the signals to the TMCC engines.

As I understand it, Lionel TMCC uses the outer rail as an antenna to broadcase a low-level RF
signal, which is picked up by an antenna in the engine.  MTH appears to use a different scheme.
I think it actually impresses its control signal on the power lines, which is picked up directly by the
MTH ProtoSound 2.0 engines.  The two different signals can't interfere with each other.  The only
problem we may have (and we can't know until we try it) is that MTH recommends wiring power in
a star configuration from a common distribution point, instead of the ring configuration we use.
They claim that this provides more even distribution of the DCS signal to all points on the layout.
We obviously can't do this (except for the power cable we have going diagonally across the
layout).  


Ira