How to Choose a DCC Decoder

  • 01 of 03

    Choosing the Right Decoder

    by Ryan C Kunkle

    With so many decoders now on the market for locomotives, switches, and other accessories, how do you know which is the right one for you?

    There are several options that will work with whatever you have. Some decoders may just give you better options for an easier installation, different lighting options, or sound. Here are a few general guidelines that will help you get to the right decoder for your next install.

    Continue to 2 of 3 below.
  • 02 of 03

    Choosing the Right Mobile Decoder

    by Ryan C Kunkle

    For locomotives, you'll want to choose from the extensive array of mobile decoders on the market. With so many out there, the selection can be as daunting as the installation:

    • Size: Many manufacturers market decoders for a specific gauge but there is no guarantee that an "HO" decoder will fit in any "HO" locomotive. It's possible that you may be able to use a smaller "N" scale decoder in an HO model if the current draw is small enough. With manufacturers packing every available space with weight and older models not designed with decoders in mind, some jobs can be more challenging than others. Creative thinking can put decoders in cabs, fuel tanks, tenders or more. For example, a decoder installation on a very petite EMD Model 40 switcher. Especially with newer models, there may be a decoder specifically designed for your locomotive. This is almost always the best choice at any cost.
    • Power: A decoder's power rating is also important, as it will be controlling a load of lights and possibly sounds. Get a decoder that is rated for the amperage draw of the model. The scale designations of the decoder can be a good clue. Older and open-frame motors will have a higher current draw than today's can motor, and some models may have more than one motor. All of these will have an impact on which decoder you may choose.
    • Plug or Hardwire: With DCC becoming a standard today, most new locomotives come pre-wired with a plug for easily decoder installation. This can save a lot of time. With our without the plug, you can also hardwire the decoder directly to the trucks, motor, lights, etc.
    • 2 or 4 Digit Addressing: Some systems only support 2 digit addresses for decoders. That is, only addresses 01-99 can be used. Later systems allowed 4 digits, 0001-9999, for more options and easier programming. Most decoders on the market today can support either, with an option to use 2 or 4 digit addresses available in programming. Decoders are preset to address 03.
    • Silent Running: Today "silent running" decoders, which help eliminate motor noise or "hum" are pretty much a standard, but it's something to check for if you are shopping for used or older decoders.
    • Lights: Even basic decoders will give you options to install a headlight and backup light. For additional functions like a Mars light, ditch lights, cab lights, etc., you'll want to choose a decoder with more functions. You'll pay a little more, but the results can be well worth it on a finished model.
    • Sound: Adding sound to models adds a whole new dimension to your layout. Today, sound can be added to a typical model for around $60 to $150 dollars, depending on the quality and size of the decoder. Some come preprogrammed for specific models or generic sounds, others can be programmed with files downloaded from the internet. The quality and specificity of sounds you want will determine the cost of the decoder.
    • Transponding: A feature that allows the decoder to talk back to the command station. This is useful if you intend to hook up a computer to control the layout to track specific trains or create other scenarios like refueling or maintenance schedules for the locomotives.
    • Price: All other things being equal, price is often the final factor in determining the decoder you buy. It may be finding the cheapest option for the features you want, or it may mean limiting the features for the price you are willing to pay. A basic decoder may cost around $12 to $15. A deluxe sound installation may be over $150. You can always upgrade to a newer or more advanced decoder later, often without any significant changes to the rest of the wiring.
    • Manufacturer: With most manufacturers following standards adopted by the NMRA, you can use decoders from different makers on the same layout and with different systems. Some modelers do prefer to standardize on one brand. Shopping around can often yield better prices and can help you learn about features you may have missed on your "standard" brand.
    Continue to 3 of 3 below.
  • 03 of 03

    Choosing Stationary Decoders

    switch decoder install
    by Ryan C Kunkle

    When choosing a stationary decoder, there are several factors you'll want to consider:

    • Twin-coil vs. Motor: The type of machine you are using will have a major impact on which decoder you'll want to use. Call "twin coil" machines use a lot of power for a very short time. Slower ​switch motors use a lot less power, but keep a "stall current" on the motor at all times. You'll want a decoder that is capable of handling these different needs.
    • Mounting: Stationary decoders give you many more mounting options than mobile decoders. Some are designed to be easily attached directly to a certain type of machine. Most can be attached to the underside of your layout by screws or double-sided tape.
    • Options: Like mobile decoders, you can get lots of options with stationary decoders to help automate your operations. These can include extra wiring locations to control the polarity of your switch frogs, automatically throw the switch as trains approach, control signals, or more. In some locations, these extra features can make wiring much easier and are well worth the investment.
    • Price: Like everything else, the price is often the deciding factor. One thing to notice with stationary decoders, however, is the number of devices a single decoder can control. Some will work with only one device while others can handle as many as eight. Taking this into account, you may find some of the more "expensive" decoders on the market are actually a bargain.