Wednesday, August 16, 2017

My Sound Decoder Function Standard

For a number of years I have been thinking through the problem of some sort of standard for function assignments on sound decoders. As we know each decoder manufacturer has decided to use their own 'standard' to suit their particular decoders. I have found this somewhat annoying so hence my 'thinking'.

I have a number of brands of sound decoders and these have varying capabilities. I can't afford to change out the older decoders for the latest types so I have to work with what I have.

I have first generation Soundtraxx Tsunami, latest Soundtraxx Tsunami 2, first generation QSI, QSI Titan and ESU Loksound 4 in steam only.

The early Tsunami has the functions in groups that is not every sound or lighting can be applied to any function you may want. This is somewhat restrictive compared with the later Tsunami 2 which can have any sound or lighting set up for any function number.

The QSI and ESU sound decoders also allow a lot of flexibility in aligning sounds and lighting with function numbers.

Working within the constraints imposed by the first generation Tsunamis of which I have quite a few I have now come to what I think is a reasonable set of function assignments or at least ones that suit me and the way I want to operate.

I am not one who wants to 'play a musical instrument' with a lot of button pressing and I am quite happy to allow the decoder to sound those random sounds such as injectors, blowers, shoveling, etc. Manual notching for diesels is also something I don't like as you can easily drive a train at notch one up and down grades with a full train load, not very prototypical.

I would have to say that I really like the Tsunami 2 with auto notching as it reads the BEMF and responds to the load on the loco. If you start a light loco it and use the throttle to notch up to say notch two or three it will do so but then once moving it will drop back and quieten right down. Similarly if it has a train load behind it it will notch up louder and then drop back as it gets the load rolling, very nice.

I also have a steam Tsunami 2 in a NSWGR C35 Bergs brass model and it also responds in a similar manner, chuffing loudly to get the train moving and then dropping back and chuffing lightly or even drifting once the train is rolling.

I believe that the TCS WOW sound decoders also work this way but I don't have one, this is the only reason it isn't included in the tables of function assignments.

I also want to work towards having working marker lights which will be a long process of course as some of the earlier models didn't have them and some decoders do not have enough lighting outputs either.

I have drawn up a diesel and a steam table for my new 'standard' and I have begun to re-program my loco fleet.

I have an NCE DCC system with the standard larger cabs. These cabs have 12 available function buttons  but F10, F11 and F12 require the use of a Shift key to access. Functions 0 - 9 are all single press (Function 0 is the headlight). Also of the basic eight functions only six show on the LCD display.

I realise that not everyone will like or agree with my choices but they are of course just my preferences.

Here is a table showing the function assignments for a diesel.

And here is the table for steam.

Please be aware that I model late 1965 and as such the diesel function assignments do not include ditch lights, etc. of modern locomotives.

Most sound decoders only have 4 outputs, some do have 6 and there is one that has 10 and these have been listed on the PDF tables.

For those who are interested there is also a decoder that has 12 outputs and it is one of the Zimo sound decoders.


Anonymous said...

Hi Ray.
A very timely post as I am installing decoders gradually to the small fleet of loco's I have and the Tsunami 2 could fit the bill on couple of steamers.
Regards Peter

Colin Hussey said...

A complex and not easy work to do Ray, but I think you have done a good job considering the need to cover more than one brand of decoders. The other aspect is that when you operate any model on layouts that may have different DCC control systems also has some problems, I think initially of the whistle function, the NCE has the seperate whistle key which is all I use as I use it for both short and long whistles, freeing up one key on the Tbone.

The aspect of a single key press that links the dynamo to all the lighting functions also is a good idea, and what I have aimed towards as well, using it in the same way to over ride any other lighting features also is an aim, as I will only be having lights on during any night time operating sessions, I also want to add the headlight function to be multi press, from off - dim - full - dim - off for night operations.

Thing for me is that I am glad that I have held off for so long in going too far into having Sound in my locomotive fleet for the reason that I am aiming to equip the majority of the fleet with the same decoder, so far I only have QSI in the Eureka garratt and Austrains 35cl, the remaining models will go to WOW decoders owing to their sound and other attributes.

Lindsay said...

Another complicating factor for marker lights (perhaps Colin Hussey can comment) is that there used to be rules about trains waiting in a loop for a cross having to display one red and one white marker on the loco. So they would need to be independently controlled. More lighting functions required.

Ray P said...


Yes, I am aware of the full marker lighting requirements however the only decoder that might be able to accomplish this is the 12 function ZIMO MX645. 8 individual outputs for the markers then head light, maybe rear headlight, cab light, tender light (C38), smoke stack light (D59 and AD60) and under footplate lighting.

The MX645 is the "standard model" for H0 scale sound in the ZIMO decoder range. It comes in a variety of formats, has plenty of power, 10 normal function outputs, 2 convertible logic level outputs, and connections for external energy storage, especially important for uninterrupted sound.

Note that the MX645 has 10 outputs plus 2 convertible logic level outputs. Not sure what 'convertible' might mean.

Of course a 4 function only decoder could be added with some interesting programming I am sure.