PTBs are the translators that allow easy communication
between older command stations and all decoders. They
in essence interpret the current flow through the newer
decoders and tell the older command station what is really
happening, based on the new NMRA standard.
With my spotty Spanish, I can order a beer and find the
restrooms in Mexico. But I cannot communicate easily
with native speakers. Similarly, there are “fixes” for sound
decoder programming problems recommended on the web.
They include adding light bulbs or resistors to the program-
ming track. They are patches. They may or may not work
with a specific command station and a specific decoder.
There is nothing about a PTB that prevents it from being used with
any decoder of any vintage. So, I recommend, if you are working
with decoders that your command station isn’t understanding,
buy a PTB for about $60 and install it between your command
station and your program-
ming track and leave it. The
SoundTraxx PTB-100 gets the
most consistent “thumbs-up”
from users. Or, get a newer sys-
tem; like a PowerCab or a V3.6
Lenz system.
The other way: on
the main
Sometimes referred to as
Ops-Mode Programming
(Po in Digitrax parlance)
or sometimes abbreviated
POM, Programming on the
Main allows you to write CVs
to locomotives as they are operating on the layout. During a
recent op session, I was doing a switching job on our club lay-
out
) and the loco I was using ran a bit faster than I
wanted at full throttle. So, I went over to our computer (running
JMRI) and opened the file for
the culprit. A quick change of
the forward and reverse trim
settings and I was back operat-
ing with a slower loco. I stored
the new setting in the decoder
on the loco and in the com-
puter as a back up.
I love POM. Yup. No question.
As I said in my column about
A Dozen DCC Myths
, there is nothing
intrinsically dangerous about
POM.
4. Drawing of a DT400 series throttle set for Ops Mode program-
ming. What is shown is programming loco number 597, CV 4 (de-
celeration) to a value of 3 in Ops Mode (Po). Note that the display
is showing you that it is in Ops Mode and what loco it is talking to.
4
MRH-May 2014
