Connecting cords and cables for the Command 2000 can
be confusing and frustrating.
Perhaps these explanations will be some help.
|Not all modular cord and cables are born equal. The MRC walkaround
cord is wired straight through, as shown at the top of the diagram at left.
A telephone extension cord with modular plugs is shown at the bottom in
the diagram at left. On this cord, the inner pair (red and green)
cross over and the outer pair (black and yellow) cross over. This
gives pin for pin connection end to end.
The photo at left shows a quick check for a correctly wired MRC walkaround
cord. When the modular plugs are held nose-to-nose, the wire colours
align, black to black, red to red, etc. With the telephone
cord, the colours will not align, indicating cross over.
is the standard colour coding of a modular jack (as seen from the back)
or a modular plug (as seen from the front.) Don't worry if yours
aren't arranged exactly like this. These are the colours for a six
pin plug/jack with all the pins used. More likely, you will find
only four pins (as in your MRC system) or two pins (often in telephones.)
And the colours may be reversed in pairs (white/blue, black/yellow, red/green.)
This is because most telephones don't care if the wires are reversed.
Unfortunately, your MRC system does.
double jack (shown from the back) follows the above colour scheme.
They are convenient for throttle stations and can be mounted in the layout
facia or on a sub-base of 3/4" plywood, or in an outlet box. They
can be strung together with four wire flat telephone cable (matching
colours) and a cable run from the command station to the back of the closest
jack. The command station end should be terminated with a 6 pin modular
plug according to the standard colour code above.
The coupler shown at right can be used for coupling two telephone extension
cords together to make a longer cord. As the opened unit shows, the
wiring crosses over. Thus if you use one of these and a telephone
extension cord to extend your MRC type cord, it will normally work.
The cross over in the coupler cancels the cross over in the cord, and everything
But be warned - not every telephone extension cord you buy crosses over,
and neither does every coupler. If using these components to extend
you MRC cord gives you strange results, you now know why.
VISIT THE OTHER PAGES IN THIS SERIES
Modifying MRC Walkarounds
An easy modification of your MRC Command 2000 Walkaround throttles will
allow them to be used in pairs without interfering with one another
Modifying the Command Station
Some simple changes to the command station allow you to use two additional
Building Tethered Walkarounds
Use two of these with your modified command station to move throttles two
and three elsewhere on your layout. Optional extended low speed control
is ideal for switching.
Building Memory Walkarounds
Use two of these with your command station, modified or not, to replace
the memory walkarounds supplied by MRC.
Return to DCC index page