KB675 Resetting a mobile decoder to factory settings

Most Digitrax mobile decoders have a global reset function, which returns the decoder's CVs to their factory default settings.This is useful if the CV values in a particular decoder have been changed with less than wonderful results. For example, you may have accidentally set the CV value for acceleration so that the engine won't move for minutes when issued a speed command. This makes it look like the decoder is not working when all it needs is to have the CV value for acceleration reset. Many of the decoders that are sent to us for repair just need to have ...

KB836 Stealing A Locomotive Address

Stealing A Locomotive AddressDigitrax systems do not allow more than one user to select and run the same locomotive address unless the loco is “stolen” (or shared) by the new user. When an address is receiving commands from more than one throttle, it may seem to be out of control.Stealing is a safety interlock that prevents operators from automatically taking control of locos that are already selected and being run on another throttle. Occasionally you may need to override this interlock to gain control of a loco. This override is called stealing and will result in having a single loco ...

KB870 Troubleshooting Guide for Digitrax Mobile Decoders

Before sending your Digitrax mobile decoder in for repair try these troubleshooting steps to see if you can “bring it back from the dead” and save a trip to the shop and possible repair charge. As with troubleshooting anything, begin checking what could be wrong methodically. Write down your observations as you work through the list to solve the problem.The most common "repair" problem we see in our repair department is decoders that are programmed incorrectly.Many decoders we receive for repair have been programmed with CV values that cause them to seem to have a problem. The good news-bad news ...

KB294 Kato RDC Headlights Reversed

There have been reports of headlight problems with some DN143K2 decoders; the unit will be running in one direction but the headlights are backwards. There is a simple fix for this problem. Set CV33=2 and CV34=1; this will remap the function outputs F0F and F0R.

KB583 Programming output voltage and Bachmann decoder programming

Q:  I have a Digitrax Chief system. I wired the programming track as per the manual, using PROGA and PROGB outputs on the DCS100. I turned on the system and checked the track voltage with a Tony Trains RRamp meter, the mainline read 14.2 volts. The programing track did not read anything. I then checked the two wires coming from the DCS100 and they did not have any readable signal. A:  The programing track connected to PROG A and PROG B will NEVER have track power on except the very instant the program message is sent.  So, you would not ...

KB557 CV29 - Configuration Register Look Up Table Method

CV29 is called the configuration register. It controls the following decoder characteristics: 1.  Whether the decoder uses 14 speed steps, 28/128 speed steps or loadable speed tables.  This affects how smoothly the loco will move and how it responds to throttle controls.2.  Whether the decoder automatically converts to analog mode when no DCC signal is present.  This allows the decoder to operate on a DC layout even though it is DCC equipped.3.  Defines the normal direction of travel for the locomotive. Normal Direction of Travel or NDOT can be changed when the motor connections of decoder have not been connected so that the locomotive runs ...

KB878 14, 28 or 128 Speed Steps-Why?

This article was originally posted on this site in 2006, but the source material dates back much further than that, probably back to the early 1990's, when DCC was an emerging control system. The article discusses non-sound mobile decoder programming operations. Many of the issues discussed in this article are less relevant when using recently produced decoders, but this text still does cover some questions which may be raised when you are using mobile decoders which were manufactured by other companies. These decoders will operate in the Digitrax environment, but you may need to make some adjustments.The earliest Digitrax mobile ...

KB530 Intermittent Locomotive Operation - Dirty Track & Dirty Wheels

Most intermittent operation faults on all layouts, not only DCC ones, are caused by bad electrical connections and poor wheel pickups on locomotives.  Poor electrical contact causes problems with sound decoder operation in particular.  Sound decoder installations usually include a capacitor to store energy to keep the sound going when the decoder briefly loses electrical contact.   When the track is dirty or corroded, it can't transmit the electricity and DCC signal needed to run locomotives.  When the locomotive pick ups are dirty or corroded, they can't pick up the signal from the track.  Check your track cleanliness and quality of wheel pickups ...

KB852 Loco Won't Stop or Start As Expected

Whoa!!!!!Each locomotive on your railroad has a mobile decoder which receives the command control signals from the command station and operates the locomotive motor accordingly.  The performance of mobile decoders can be adjusted by changing the Configuration Variables (CV's) of the decoder.  You can improve the speed performance of a locomotive by adjusting its start speed (CV02, V-Start), its mid-range speed (CV06, V-Mid) and its top speed (CV05 - V-Max).  You can also adjust the acceleration (CV03) and the deceleration (CV04).If the deceleration CV value you set for a particular loco is very large, this can make it look like ...

KB693 Test A Mobile Decoder Using an LT1 Decoder Tester

The LT1 is a simple decoder tester. Decoder Testing Instructions1. Prepare the cable for use in the testing procedure, by stripping the insulation from the Red, Green, Black, and Yellow wires. The Blue and White wires are not used and can be cut off the harness.2. Twist the RED and YELLOW wires together. Twist the BLACK and GREEN wires together. 3. Hook up decoder as shown in Diagram 2.4. Use your throttle to select the decoder and run it in the forward direction.5. One of the two center LEDs will light as the motor voltage from the decoder increases. Use ...

KB933 Motor Isolation Protection FX & FX3 Decoders

FX3 decoders have motor isolation protection. If the decoder senses that the motor is not isolated, it will not run the motor. In this case, you will be able to control the loco’s functions but the motor will not work.FX decoders will blink the loco's lights when power is first applied to the decoder to warn you of a short circuit in your installation. If you see the lights blinking, immediately remove the loco from the track, locate the short circuit and correct the problem before proceeding. Do not leave the loco on the track with blinking lights because eventually, ...