DCC Impulses Column - 5
Several folks got on the MRH forum connected with that March
column and disagreed. Check it out for more details. However,
they failed to show that POMwas dangerous. What they did show
is that ANY programming possibility in the hands of someone who
isn’t fully cognizant of their actions can cause problems. There is
a solution: don’t let guest operators (including club members) use
throttles that have any possibility of programming things on the
layout via any mode.
There are, as I said above, two methods of POM. What I’ll call tra-
ditional and Blast Mode.
Let’s look at traditional first. When you enter this mode, the com-
mand station asks you what loco to program. That’s a strong clue
you’re entering POMmode. You need to verify or correct-and-ver-
ify that address. Once you get past that gate, nothing you do will
impact any other loco on the layout. With this method, you can
run the loco and tweak to your heart’s content, that’s why I love it.
A similar method is Blast
Mode programming. This
came into vogue as part of
the Digitrax Zephyr system
as a work-around for pro-
gramming sound decod-
ers without a PTB. If you
choose to use this method,
follow the directions on
the Digitrax web site
very carefully. Failure to do
so may result in messed
up loco programming.
Because of this danger and the intrinsic inability to read what
you’ve written, I recommend against Blast Mode programming.
Get a PTB instead.
Two types of programming track
Okay, this may be a bit of a stretch, but there really are two
types: one on the layout and the other on a workbench. There
are special precautions necessary with the layout version to
assure isolation from the DCC track in all circumstances.
Programming track on the workbench
I have a track on a shelf above my workbench and use a NCE
PowerCab to run it. The PowerCab has enough oomph to run
most of the locos I work on, even some G scale models. It
doesn’t need a PTB to talk to any decoder I’ve ever put on it.
It reads out the amount of DCC current being consumed on
the test track. With a NCE USB adapter, it allows me to run
DecoderPro. I know of many dyed-in-the-wool Digitrax users
who have a similar setup on their workbench.
5: Digitrax Zephyr – the system
that put Blast Mode program-
ming on the map. Photo cour-
tesy Digitrax.
5
MRH-May 2014
