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the motor voltage/speed curve of the DCC loco from stop to full speed has 128 discrete speed steps. This means that you have 128 discrete speed steps at your disposal for excellent speed control, especially at very low speeds. 128 speed step operation will give a significant improvement in speed control over 14 or 28 step operation. 128 speed step operation is only offered in advanced and professional level DCC systems.

An expression used to describe an electrical wave form that cycles or alternates above and below 0 volts. In the U.S., household electricity is 60 cycle, alternating 60 times a second, 110-120 volts.

The rate at which the decoder increases from one speed step to the next in response to a new increase speed command. Use CV 03 to set this value for each decoder. This feature is used to simulate train weight and to cause your model to respond more prototypically when you increase the throttle.

the special address used by DCC systems to send speed and direction commands to operate locomotives that do not have decoders.

each system has a certain number of addresses that it can handle. Basic DCC systems usually handle between 6 and 16 addresses. Advanced systems usually handle between 99 & over 9000 addresses and Professional systems almost always go to 9000 or more addresses.

a number assigned by the user to a particular mobile or stationary decoder. The DCC system uses the decoder address to send commands to the appropriate loco or accessory. In the case of signals, stationary decoder addresses are used.

Storage of the consist information in each decoder. The locos can be added to and deleted from the consist in any orientation. This method requires that all locomotives in the consist be equipped with decoders that support this feature(EPF decoders). This method allows you to set up a consist that will be "transportable" from one DCC layout to another but you must be sure to always put the locos back on the track in the same order and orientation you programmed them for or you can get some unexpected results.

the motor voltage/speed curve of the DCC loco from stop to full speed has 28 discrete speed steps. This means that speed control will be limited to 28 steps. 28 speed step mode gives fine speed control. Increasing to 128 speed step operation will give a significant improvement in speed control, especially at very slow speeds needed for prototypical switching operations. Advanced mode is offered in most command stations because there are many decoders on the market that are not capable of 128 step mode operation.

a list of aliased addresses and their associated decoder addresses stored in a command station.

Lets you run 2 digit address decoders with 4 digit addresses by selecting them from the system Alias Roster. This feature gives you the ability to operate all DCC equipped decoders with 4 digit addresses. This is a function of the command station, not of the decoders.

a turnout where throwing the turnout does not change the rail polarity. Also called non-power routing turnouts.

the unit of measure for electrical current used or provided by an electronic device. The current draw of most HO can motors is between .5 and 1.5 amps. DCC boosters usually provide between 2.5 & 10 amps. This means that in HO scale you can run between 4 and 6 HO locomotives on a 5 amp booster.

A locomotive operating on a DCC layout without a DCC decoder installed. Also called a Conventional Loco.

When a DCC decoder does not see DCC packets on the layout it changes automatically to DC operation. Digitrax decoders support analog mode conversion but not all DCC systems do. Analog conversion can be disabled by programming CV29.

the particular method and/or arrangement of system hardware components used a given DCC system (or other computer based system) for communication within the system. Examples of system architecture in the DCC context are peer-to peer communication and polled communication.

the rotating frame that supports the field coils of a motor.

a combination of lights or positions on a railroad signal which has a defined meaning. This meaning is the signal's indication.

a feature of some DCC boosters which allows a train to enter and exit reversing sections automatically without the need for the operator to throw a switch to match track polarities on either side of the reversing section.

American wire gauge (AWG) is used in the United States and other countries as a standard method of denoting wire diameter. The higher the AWG number, the smaller the wire diameter.

the voltage generated by the rotation of the motor armature. EMF is short for electro-motive force. Measurements of back emf are used for speed stabilization.