Download - O scale trains

Fig. 1
4
load Look at the wiring diagrams. At the bottom-right is a relay
that is driven by any of the function leads from the decoder,
even the headlight function. The specified relays are 12V and
only draw 37.5 mA (Radio Shack 275-241, 275-241A, or All
Electronics RLY-461). I used the relay to run the brush motors on
the sweeper. I also used a relay in one car to turn on the headlight
and the interior lights, both on one circuit. Photo 5 shows
the size of the relays relative to a pencil. They can be mounted
under a car and painted to look like part of the car’s underbody
equipment.
To set up a decoder for operation, we have to ”program” it.
Don’t run away! You don’t have to know about computers to do
this! Programming means setting configuration variables (CV’s)
to certain values. Every DCC manufacturer provides a method
to program CV’s with their system. It may be accomplished
using a throttle or with the system’s command station. While a
decoder will have 50 to 100 CV’s, only a few need to be set for
basic operation. CV1 is set to the ”unique” address for this car.
It allows only a two-digit address, so I used the last two digits
of the car number. Most decoders will also allow a four-digit
address, but that is the next step beyond basic.
CV29 is a multi-function variable. It can specify which end
of the car is the front when the decoder is set for ”forward”. CV
29 can tell the decoder to run on a normal DC voltage, and if it
should use the two- or four-digit address. It can also specify the
use of a custom speed-table. Speed tables allow the alteration of
5
motor response so
cars with different
motors can be
operated together
as a multiple unit
consist. I usually
set CV29 to a
value of 06. That
value gives me
forward operation
and allows the car to run on DC layouts. Other CV’s set minimum
start voltage, maximum voltage, acceleration and deceleration
momentum and more advanced options. So, to get our
basic DCC trolley running, we set two CV’s, CV1 and CV29.
Do you want to make decoder programming a little easier
or get into advanced options There are computer interfaces and
software available for some DCC systems to program decoders
(and much more). For Digitrax systems (I’m using Digitrax.)
there is a device available to connect the Digitrax network to a
computer, called ”Locobuffer”. With Locobuffer and Decoder
Pro software (free on the Internet) you can program decoders
and save the configurations on the computer. There is a throttle
included in Decoder Pro that can control a car on the layout
from the computer. You can write a file of commands and have
the software play it back, providing the possibility of automatic
operation. This software is being enhanced by the users. With
signaling, turnout control, and transponding decoders available,
who knows what may develop
I hope I have convinced you that DCC is not difficult. What
I have described is how I have integrated DCC into my trolley
system. Everything I mentioned can certainly be applied to a
"steam" railroad. The major difference is you will need decoders
with a greater current capacity. Find a few friends of friends who
are running layouts with different DCC systems and see how it
works. You should try systems from different manufacturers to
see what options are available. Be sure to try different throttles,
since the throttle is your main interface with the system. If you
are not comfortable with the throttle, you will not be happy with
the system. Have fun!
u
Mort Mann
Mort Mann, the founder of Sunset Models, passed away
suddenly on Sunday May 6, 2007, after attending his granddaughter’s
college graduation. An Air Force Korean War vet,
Mort began his professional career as an engineer in New
York City, developing the first radar array at O’Hare Airport.
Mort founded Sunset Models in the late 1970s, importing
HO and O Scale models. In the mid-90s, Mort added
O Scale 3-Rail brass locomotives to the line, and the business
became known as Sunset/3rdRail. He was inducted
into the O Scale Hall of Fame
at the 2006 O Scale National
Convention in Parsipanny, New
Jersey.
Mort is survived by his wife
of 51 years, Gerre, three children,
and six grandchildren.
Scott Mann will now take the
helm of Sunset/3rdRail.
We offer our condolences to
Scott and his family. Mort will
be most fondly remembered.
July/August ’07- O Scale Trains • 53