My function solution

As a wrapup to my posts on sound decoders and function remapping, let me tell you the solution I have arrived at. First, my kudos to David and the rest of you who are trying to adjust similar functions so they coexist and also those who are remapping functions. I also applaud those who use the same types of decoders in locomotives to be used in a consist–that greatly simplifies the task of dealing with mismatches of function. So here’s my solution to these problems.

Since most of the folks in my area who make the monthly rounds of operating sessions bring along their own Digitrax utility throttles I have to take that into consideration. These throttles have access to all the functions from F0-F12, however for those above F6 you have to hold down the Shift button to get to them. This is a real limitation because it is difficult to press the Shift and press another button simultaneously while also running a train, uncoupling cars, and manipulating a set of car cards. Consequently I wanted to have the most commonly used functions mapped to F0-F6. So here is my lineup.

First, I made up a table listing the default function assignments for the five brands of sound decoders I own. That way I was able to quickly pick out which ones I would leave in their default positions and which needed to be remapped. It also made it easier to decide on a common set of functions. I left functions F0-F2 on their default settings since these are essentially standard for all decoders and throttles. I then assigned the grade crossing signal to F3, which seemed to be a natural location next to the horn/whistle at F2.

F4 can have a number of different functions depending on the decoder brand so I assigned it to the switching mode. F5 is often set for the dynamic brake on diesels and blow down on steam so that’s what I set if for in my scheme, for all but Digitrax which can’t easily be changed. The big function left was the brake function which varies greatly among decoders so I moved it to F6. Although I don’t expect it to be used often I moved the headlight dimming function to F7 and left F8 as the mute. F9 and F10 were assigned the notch up and down function on diesels and left open on steam. Since that covered all the functions I wanted, I left the rest alone.

Where possible I used the automatic functions to activate brake squeal and to use Rule17 lighting as supported. I did not activate the automatic bell and whistle when the locomotive direction is changed but I do have the bell set to ring when the grade crossing signal is used. I make all these changes when I install a new decoder or purchase a new locomotive. Like some of you I use car cards, including a locomotive card that has a list of the function assignments on it. That way operators have that information available when they receive a train assignment.

Making these decisions only took a few minutes but making the programming changes was a bit more protracted. However, DecoderPro speeds the process with its point and click interface. Having the major sound functions assigned to the same buttons on all my locomotives (except the one Digitrax decoder in my ALCO RS1) makes it easier to actually use the sounds prototypically. It also alleviates the frustration of not knowing which button to press when you want something to happen and makes cheat sheets a thing of the past.

Fortunately most of my sound decoders are WOWSound and Soundtraxx which makes my job easier. I only have 2 LokSound decoders and one Digitrax. On the BLI side I have 2 diesel switchers and 3 steamers so that won’t be too bad either. I have been working more with the LokSound decoders and I agree with those who have said they are confusing to remap using DecoderPro. I am putting together information on the LokSound sound slots and will have more to say on that later. I will say they are making an attempt to standardize them among sound projects. I am planning an article for my DCC Corner column on programming LokSound decoders using both DecoderPro and the LokProgrammer so I can’t go too far without running afoul of my agreement to publish new material there first.

The LokSound decoders are different in more ways than one. For example there is no grade crossing horn sequence so I am just substituting a short horn on F3. And you cannot simply remap sound button assignments with a Digitrax sound decoder–you have to go into the sound project and modify it internally. So that one decoder probably will not get modified anytime soon. You have to be flexible when trying to standardize a whole fleet of locos with dissimilar decoders because of these differences. Sometimes that’s the best you can do. Plus the sounds that are most important to me may not be the same for you. Give this process a try and see if it works for you.


  • Great series Larry. When you use the Loksound programmer and their software, remapping sounds is a little easier than DecoderPro. I’ve been using it for a very long time and I am comfortable with it. On the Loksund decoder grade crossing . I own the programmer and when I purchased the original PCM Reading T1, they used the N&W “hooter” which was about as wrong as using a Nathan 5 chime . I had recordings of the 2100 from a friend that helped with the restoration so I used it to create a “grade crossing” sound file with a simple audio wave mapper like Audacity. Loksound has the ability to use “user” files into sound slots. So I used the correct whistle, added them to the appropriate slots, and my T1s have the correct whistles from the Reading Company. I also created files for the Con Cor Reading Crusader for a QSI Titan. Thanks for your great help.

  • Larry, On WOWSound decoders, do you remap the brake release function as well? IIRC the brake application is F7 and brake release is F6; or do you leave them both on F6?

    • I had not been doing that but after using the default combination of F7 for the brake and F6 to release it I think I may make F5 the brake release. You can get away without doing it since just moving the throttle a will also release the brake. That is the way the owner of another layout I operate on has his WOWSound decoders mapped so it would make it easier on the crews to have a local standard. It would be nice to be able to map both the brake set and release to F6 but I don’t think it is possible with WOWSound. Of course Soundtraxx uses F11 for both functions and as I remember once the brake is set with F11 the loco won’t move until it is released.

  • Thanks Larry very good timing for me as that is what I am working on right now. My diesel mapping is very similar to yours except I kept the short horn and added a F11 and F12 to mine since I use the DT 402 throttle. I still have to do my 9 Lok Sound locos but maybe this weekend I will attempt. Like you the Digitrax will not be changed but run only in consists together. My Steam fleet is much smaller at 14 locos and mostly WOW and Econami/Tsunami 2 so I will probably use the same choices you have made and add a F11 and F12. I do have quite a few BLI steamers because they pull so well on hills but I have replaced the Paragon decoders in these with either Wow or Econami. I do like the drift on and off found in the Econami steam decoders so will try and use this function probably in F9 and F10. Thanks again.