Introduction

Digital Command and Control (DCC) is the modern way to control a model railroad. This article gives a background. I have decided to use Digitrax’s implementation of DCC described here. Digitrax includes a local area network to their offerings, LocoNet,  which provides communication separate from the power/control provided to the rails as well as locomotive decoders that work with the LocoNet. To get started, I bought the EVOX Evolution Express Advanced 5A/8A Starter Set which contains items I will need, a combined DCC command station/booster, a wired throttle, and LocoNet panel as well as cabling.

The following sections are DCC components I may use on the model:

Command Station/Booster

The Starter Set has a DCS 210+ combined command station and booster. The device has a built-in USB controller to connect to a computer so I can use JMRI. I have a test laptop running Ubuntu at my modeling desk and my next project is to hook it all up and see if I can program a locomotive on a programming track. Command statins and boosters may need fans to provide airflow for cooling. They do have large heat syncs on the outside of the case at the back.

Boosters

These are devices that simply provide power to a defined block (often called a district) of the model railroad, an example is Digitrax’s DB210 (in the name, the “B” denotes booster). This booster will power one district, the DB220 can power two. A booster needs to be connected to a command station by LocoNet as well as an electrical ground wire between them to provide a common zero volt standard. The ground wire needs to be able to conduct full track current.

Power Districts

Recommended practice for short circuit control is to create sub-districts to each power district using the Digitrax PM42 controller. This controller can handle up to four sub-districts. The edge connector for the PM42 can be used with a female connector, here.

The rails at the junction of power districts need to be double gapped, at sub-districts, single gapped.

Throttle

The Starter Set has a wired DT602 Super LocoNet Throttle, this allows a user to control locomotives and other devices on the layout.

Turnout Controllers

The new Digitrax DS74 Quad Switch Stationary Decoder can control up to four switches or eight layout lights.

Switch Machines

These are remote control devices that actually flip the switch, it can be controlled from a control panel, either a fascia hardware or software panel. The two manufacturers that I have considered are Tortoise and Cobalt.

The Cobalt have a DCC-ready switch motor which would not require a controller. The on-off-on switch would work well with a either a hardware or software panel.

Occupancy Detectors

These devices allow trains to be detected within a specific block. This is to help with prototypical signaling and also transponding, this allows panels to show where trains are. An example would be the Digitrax BD4N. I am not sure if I will use block detection, or whether I will use powered blocks, requiring boosters, for this size layout, I may need to. I also need to research the correspondence between detection blocks and power blocks.

Sound Decoders

These are installed in locomotives to provide realistic prototypical sounds. Decoders are built for specific locomotives due to internal size restrictions.