TTS Class 50 Decoder Speed & Sound Problems

[pd91223]

I've just installed R8123 TTS Sound Decoder in my Hornby R3471 Class 50. Previously this had an Omni DCC29 decoder installed and worked fine. 

 

RM (v1.71) did not recognise the TTS decoder, so I selected the "TTS Decoder (Diesel)" option. Having reset the DCC ID and read the CVs the loco's lights work, but there's no sound. The speed is limited to 1mph even though I've selected 70mph for Cruise speed & 10mph for Shunt speed!! Underneath the Cruise speed it says (in blue) "Max=1".

 

I've installed TTS in 2 other locos, a Class 20 & a Class 37 and both work fine.

 

Tomorrow I will reset the decoder to DCC ID 3 to see if that makes any difference. Meanwhile, I seem to remember another thread where someone had a similar problem with the speed being limited but I can't find it! Any suggestions would be welcome before I start any other diagnostics or return the decoder. TIA.

[Britannia Builder]

I think this is the thread that you are looking for:

 

https://www.hornby.com/uk-en/forum/post/view/topic_id/27840/?p=1

 

It seems that deleting the loco in Railmaster and then setting it up again is the way to solve the problem - there's obviously an intermittent bug in there somewhere.

 

Regards, John

[96RAF]

Unfortunately with each new batch of TTS variants we are likely to see an ongoing increase in value for CV7 which defines the firmware state and which RM uses to call up the associated CV listing.

 

If the OP had an Elite he could read this value direct (not that it would help in RM), but not with an eLink via RM as although it reads the value it simply tries to match it to an entry in the database. 

 

More unfortunate is the fact HRMS cannot hope to keep up with all these changes. Maybe an interim RM workaround could be if the exact value is not in the database but the value is => xxx then it calls up a generic steam or diesel CV listing with typical cruise and shunt speeds, etc.

 

Edit - as you have sucessfully added other TTS locos it is assumed you have listed the sound functions correctly with on/off suffix as applicable in order to get the sound to work. Try adding the basic loco R-number, add the sound profile and see if it works on address 03. If so go into the CV listing and simply change CV1 to your chosen address before reading any values.

[pd91223]

Thanks @RAF96. I'll try this too.

 

It was odd that the default Accelerator CV value was set to 128 but the instructions say it should have been 015. There are 3 generic TTS Decoder settings available: Diesel, Steam and undefined. I'll try the undefined too if nothing else works.

[96RAF]

The loco will work in RM perfectly well setup as a basic loco with TTS functions laid in by hand if necessary.

 

CVs can be written to in RM without having to first read the decoder, hence knowing the decoder type in RM is just an added extra unless you want to see what values all the CVs applicable to that decoder have at present.

 

Think about it - you would have little interest in the decoder firmware state if you were not using RM, you would just read then amend any CVs of interest.

[pd91223]

Some progress ... but not a lot! 

 

Deleted original loco and started again from scratch. Ignored TTS decoder options in CV7 (remember RM v1.71 does not recognise decoder) and read all CVs. When I read them for a second time, some of them had changed, e.g. CV3 (Acceleration) had changed from 128 to 160 (default should be 015)!

 

So, I did a reset (CV8=8). CV3 became 15 (as expected, although on arrival it had been set to 128); CV29 became 2 (as expected, although on arrival it had been set to 6). Of more concern, however, is that CV151, which according to the instruction leaflet has a default value of 64, was reset to 0!! ☹️

 

I put the loco on the main track (DCC ID left at 3). Lights work fine as before; max speed now set as 90, although it takes an age to get any response from the slider - is this because of the incorrect value of CV151? But ... still no sound. 😢 F1 is set as "Sound on/off" selected from the built-in drop-down options menu. There's nothing from sounds (e.g. Guards Whistle) that ought to play even when the engine sound is off.

 

Faulty decoder?? Anything else I can try before returning it?

[pd91223]

I returned problem decoder to RoS last Friday. Today the replacement arrived, no quibbles. Decoder installed and sound works fine. Presumably the previous one was faulty as I'd thought.