DCC for beginners

Well, it's been a month since my last post so I was thinking about what would be of interest to my new model railroading friends when it hit me - Almost everyone who comes to my table during train shows to see how to get started in the world's greatest hobby asks "What is DCC". With all the hype and tech talk it can get pretty confusing. For the starting model railroader it should really be straight forward, so here goes.

Whether you're building a small tabletop layout or one that will fill a whole room, DCC (short for Digital Command Control) will make the experience more enjoyable. As I demonstrate in the shows I sell at, you can run three trains on an N scale layout in a small 2'x4' space with just two wires to the track. In fact, with the Command Station I use, you could run 10! But I'd be a nervous wreck trying to keep them all from running into one another on that 2'x4' N scale layout.

The many DCC books and manuals available today are designed to educate the hobbyist with the theory, technical details of how it works, and terminology of the science while we just want to set it up and use it. Not many of us know why a computer will do what we want, we just know how to make it do it. We don't care about the science since we don't plan on designing our own computer.

DCC is much easier than a computer. But, of course, it is a computer application and, in fact, you can hook most of the more sophisticated DCC systems up to a computer to do more fancy things.

Basically, DCC requires three things: A layout with decoder equipped engines; a command station to tell the engines what to do; and a power supply to drive it all. Fortunately, any layout that will run DC engines can run DCC engines as well. AND MUCH EASIER!!

With a DC layout and two engines on the track you must wire separate parts of the track for different speed controllers and switch the controllers to each isolated electrical block to the unit that you want to use for the engine in the block. It sounds complicated and the wire and operation ARE! The problem here is that the power supply can't differentiate between the two locos on the track, so the operator must switch the speed controls with toggle switches. Running trains this way has been the only way for many years with HO, and now N, scale trains. Without the blocks, fancy wiring and dual power supplies, both engines would run in the same direction at the same speed ALL THE TIME.

Just like your computer lets you use your inkjet printer for some printing and you then can select your laser printer for other printing, the command station can send commands to one engine and the others will ignore them. And that one engine will continue following its last command until you address that engine again and send a change.

When you installed those printers on your computer you assigned them a name. When you buy a new engine and place it on the track with DCC, you must assign it a numeric ID. As you might suspect, that ID must be different then the IDs you've assigned to your other engines and it must be compatible with your Command Station.

Once that engine has been assigned a unique ID it can run on the same track as all your other engines and be controlled completely and independently of all the others with just two wires powering the track from the Command Station.

Well, that's a start. How each command station controls the engines is a little different from one system to the next, but they all have a direction button, a speed control and the all important STOP.

Let's get a discussion started and I'll cover more ground in the next installment.