For the purpose of discussion throughout this site, a loco that does not have a DCC decoder installed is called an analog loco, and a loco that has a DCC decoder installed is called a DCC loco. A layout controlled with a traditional DC power pack is called an analog layout, and a layout controlled by a DCC systems is called a DCC layout.

There are two aspects of DC analog operation with DCC:

1) Controlling a DC analog loco on a DCC layout
2) Controlling a DCC loco on an analog layout.

This page dwells on controlling a DC analog loco on a DCC layout. Refer to Analog Conversion for information about a DCC loco on an analog layout.

Controlling a DC analog loco on a DCC layout is a system feature - obviously, because the loco does not have a decoder in it. Most systems have this feature. There was at least one in the past that provided information on how to modify the system to have this feature. Likewise, most systems provide for controlling the analog loco with a throttle the same way you would control a DCC loco. However, the one that was modified had to control the analog loco from the command station instead of from a throttle.

That's the basics of DC analog control. Each manufacturer has their own ideas about how far to take analog control. Digitrax treats an analog loco exactly the same as any other DCC loco by selecting it with address zero "00". This even includes the capability to MU the analog loco to DCC locos - that is, of course, as long as that analog loco runs at about the same speed as the locos it's being MUed to.

Analog locos will NOT traverse automatic reverse sections like a DCC loco will. This means that if you have an analog loco MUed to a DCC loco, you can't take it through a reverse section without special manual control. If running an analog loco through an automatic reverse section by itself, the loco will enter the reverse section normally. But when it tries to exit, the auto-reverser will reverse the polarity under the loco which will reverse the loco's direction. At this point the analog loco will simply go back and forth inside the reverse section unless you intervene. The best way to handle this is to get your finger ready on the direction button. Change the loco's direction the instant the analog locos's front wheels hit the gaps to exit the reverse section. If you reverse the direction of the loco at the same time the auto-reverse reverses it, the loco will continue out of the reverse section as normal. With a little practice, you won't even see a flinch out of the loco.

You can generally run two or more (within reason) analog locos together on a DCC layout, the same as you would on a regular DC analog layout. Exiting a reverse section with two or three analog locos is no different than with one. When you, and the auto-reverse, reverse the direction for one, it reverses it for all - the same as it would be on a DC analog layout.

Some DCC companies advocate, even advertise, running one DC analog loco on the layout as a regular matter of course. We do not advocate this for several reasons.

A DC analog loco will make a singing noise when running - something that companies who advocate this don't tell you. This noise will get annoying after a while, and will detract from your model railroading pleasure.

Most properly running and serviced locos will run better after converting to DCC than they did before. Therefore, adding a decoder will provide you with more operating pleasure than without the decoder. And after all, the whole reason you switched to DCC was to have better running trains ... right? So why relegate one loco to running as it did before switching to DCC?

In the early days of DCC, when decoders were $50 each, it was understandable for a person to want to run one loco without a decoder. But with some decoders being around $15 these days, this reason is gone. For $15 you can have a quieter, better-running loco. Why wouldn't you want to have a decoder in every loco you plan to run?

So, what's DC analog control good for then?

1) It's a way to test your new loco before you install a decoder in it. If you don't have a separate DC analog layout (which most people don't) you need a way to fully test the loco before you open it up. If there's something wrong with the loco, you want to return it to the dealer BEFORE you install a decoder.

2) It's a way to allow a friend who brings a DC analog loco to run for the session.

3) It's a way we can occasionally run a normally "display only" loco, just to see it go once in a while.

It's important to have DC analog control; not to run an analog loco as a regular course of operations, but to run the occasional analog loco when needed or desired.