I am in the process of building an HO or N gauge model railroad (first timer). I have been looking into a DCC system but there is no specific information on how to built and wire (mainly wire) the layout. Would it be better to use one of Atlas plans and hook up the DCC afterwards or how do I wire the RR with DCC from scratch?

Thank you for any input.


-- Frank Magourilos (, November 15, 2001


Dear Frank,

Unless you have something very complicated and large in mind for a first train layout, DCC is very simple. Typically DCC systems require two wires from the DCC system to the two rails.

This is unless you are going to have reverse loops, power routing turnouts, turntables, and want to have multiple power districts on your train layout.

First, select your first layout from the Atlas Track planning books to get an idea of layout operating scheme and what products are required. Is the layout designed for single track, double track, multiple locomotives, etc? The great thing about DCC on a small layout is that it will increase your flexibility to run multiple trains and not have to worry about flipping selector or connector switches, toggles.

Second, get the Digitrax "Big Book of DCC" or speak to a knowledgeable retailer of DCC to help you define your DCC needs. Generally DCC makes your train layout less complicated and reduces wiring.

There is no way around research and asking questions so that you are prepared to construct your first layout and will have the right products to get it done. Good luck.

-- David Butts (, November 20, 2001.

I've found the same thing to be true, I've bought books been over all kinds web sites and frankly DCC Has me somewhat stymied. I find that most info comes from people who seem to have quite a electrical background and have a basic understanding of electrical principles. I've played with electronics and computers, never really understanding much. So I'm not someone who goes into these things with a real fear. I have to admit I'm getting a lot better with understanding. This not is not for me but for many others who are simply confused and have little help in undferstanding. What most people need are guides that simply show how to do this. Maybe in the form of a complex medium sized layout diagram with explanations that can be understood. Although I've not completed my track work so I can expeiriment I've spent 4 to 5 years studying Dcc. Frank I understand what your saying

-- Raymond Harnist (, September 09, 2002.

Actually the solution for the majority of modelers is transparently simple. Powering locos through 2-rail track can be tricky, but easy. Look for the thin "how to wire your model railroad" books at the loco hobby shop. These are written for DC throttles and those fundamentals still apply. But you won't need to separate the layout into multiple track control blocks. Simply ignore those parts and connect all the track as one big electrical section. Once you have a track plan that works with a DC throttle, simply substitute your brand choice of DCC controller/booster in its place. If there is a reverse loop track section, provide insulated rail gaps and use a DCC auto-reverser to power that section. Once you have done that, it is then easy and fun to control more than one loco on the same track layout, just like the prototype. The engineers and dispatchers of course, must be responsible to avoid collisions.

The difficulties start when older locos and rolling stock with poor wheelsets are used with poorly constructed track switches. With DC, power to the track is limited by the speed setting of the throttle. A momentary short in the wheel/track circuit (such as when the back of a metal wheel flange brushes a wing rail of opposite polarity while crossing a switch) causes only a minor interruption/hesitation of motive power. At worst, the loco may stall as it attempts to pass through a switch at low speed. Since the user is controlling only one loco with that throttle, it is only a minor annoyance.

With DCC, full power is available on the track at all times, and it is used to power all locos, not just one. So now if there is a "minor" short circuit, all the power from the DCC booster can flow through it. The result is usually an over-current trip-off of the booster, which shuts down the whole layout for a few seconds. [Hopefully with no other burn-out problems.] If you have more than one loco running with more than one engineer/operator, what used to be a minor annoyance now becomes a problematic nuisance. Much of the discussion in this and other forums is about how to prevent those problems by fixing of track switches and other equipment or separating track sections into separate electrical power districts.

A second level of DCC discussion forums relates to how to select and use one of the DCC system brands or loco decoders to do a particular function, or how to identify and resolve an operating problem. Before DCC there were many magazine articles written on how to build your own DC trottle. Each designer/inventor claimed to have a better product some form or another. Today we see & read about similar claims about DCC systems and the wide variety of loco decoders. The difference is that DCC is far more flexible (read complicated) and can do so much more than just make a loco run forward or backward. Since it is more versatile, there are more things that can go wrong.

For a small layout user, selecting the right DCC system that is easy to operate is the most important step. If it is easy to operate and reliable, you don't need to be overly concerned about how it works.

-- Don Vollrath (, September 12, 2002.

Hi Frank and Raymond.

Frank, I assume by the 2001 date, you now have a plan of action. Raymond, I am a DCC newbie (1 year) but I am installed, running and learning. I hope I can add some insight.

First -- run don't walk to DCC. Since you are starting out, you have no legacy of old wiring and switch selectors and all that other Atlas stuff. It really is just two wires. Honest.

I used the Atlas layout HO-35 (Berkshire Valley Route) for the basis of my layout and modified it to something a little larger (basically the 4 X 12 design with a 4x4 dog leg. I also scrapped the reverse loop from the top of the figure 8 to the bottom of the figure 8.

After a little research, I selected the Empire Builder II from Digitrax. I used the accessory AC portion of my Tech 220 DC transformer as my source for the 15V AC for the booster box. I then ran two reasonably heavy gauge wires (14AWG I think) from the booster to the rails. My switches are all new PECO Insulfrog and a Shinohara double-crossover. They appear to be DCC-friendly (read: no need to alter them with jumper wires, cuts and little light bulbs. Um, that is all there was to the power wiring.

Now the scary part -- installing the decoder. I removed the shell of a loco and saw the wiring. Beads of sweat formed as I contemplated having to cut wires (read: ruining a perfectly functioning loco). I read, re-read and then re-read again the instructions for mounting the DH142 decoder that came with my EB II.

I took the bold step and cut a wire. Then another - then another. I was nervous but persevered. I placed the loco with the decoder installed on my track and turned on the booster. It worked!!!!!!!!

Lessons learned --

LL1 - Read the instructions

LL2 - String a long length of heavy gauge power wires under your layout in a snake pattern below your the mainline of your layout track (red and black worked for me). Get those little red sticky dot labels from Staples and place them along one side of your track so you know which rail will be connected to the red wire. Drop many smaller gauge red and black wires from the spurs and the mainline at some regular intervals (say every 4 to 5 feet). You want lotsa power to the rails.

LL3 - Read the instructions.

LL4 - Make sure your track is clean. Stall and sputters from your loco are probably due to a loss of power at the rail where the stall occurs or the rail is just dirty. The loco, the booster and the decoder are probably running just fine.

LL5 - Um, did I mention, read the instructions?

LL6 - Don't cut off too much excess wire from your decoder or loco unless you really have to. If you make a wiring goof, you can get a 2nd chance if you have enough wire length left.

LL7 - When things don't go as planned -- read the instructions!

LL8 - When things do go as planned, read some more instructions and make it Miller time.

You cannot be squeamish about cutting the wires in your loco and unless you have plug and play decoders into plug and play locos, be prepared to do some soldering. Soldering and model railroading are not exclusive.

I hope this helps. Send me an email if you have more questions or post through this board.

Doug Fraser

-- Douglas Fraser (, November 14, 2002.

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