Poorly class 31 TTS decoder

[Izzy]

I have one of the original issue Class 31 TTS decoders. It had a hard life so owes nothing, being used as a guinea pig in quite a few locos just to see what resulted, and hooked up to several different speakers along the way. Recently I went to use it yet again to discover the sound level has dropped through the floor and it also sounds poor, muffled and with a whistling background. I can just about get a usable sound level by hooking up a Zimo dumbo 26x20x8 speaker but the high background noise isn't brilliant over any other than a short time period. I know poor sound quality is usually down to iffy connections but would this tend to indicate that the amp has been damaged in some way and it's gone past it's sell-by date?

 

I've just stuffed it into a little O gauge freelance 4-wheel diesel shunter and would get another if they were still around, but sadly they don't seem to be.

 

Thanks,

 

Izzy

[RAF96]

Have you tried a sound reset by writing value 5 to CV8.

[Izzy]

No I haven’t. Thanks for that I’ll give it a go.

 

Izzy

[Izzy]

Well, I tried a sound re-set followed by a full fat one but sadly neither made any difference. Feeling that it seemed a lot like poor radio reception - a bit like listening to Radio Luxembourg for those that might remember such things - I though perhaps changing the speaker wires and re-making the connections on the decoder might cure it. Making sure that there was no possibility of a low level current drain/short anywhere. This was also in vain, no change at all. So I can only conclude that something somewhere has suffered. As the decoder otherwise works quite okay it seems I’ll just have to live with it and keep a lookout for a replacement. 
 

With just three O gauge locos to chip - they have sat in the loft for over 20 years so well before I went DCC - I don’t want to spend a small fortune, or even a large one, fitting full fat sound decoders as I have with most of my 4mm stuff. They will only run a few feet up and down a micro plank I have made. But it would just be nice to know what has caused it to go funny, so I could avoid it happening again if possible with the other TTS decoders I have.

 

Izzy

[cravensdmufan]

Can't really help you with the sound problem Izzy but will follow with interest as I have around 20 odd TTS decoders fitted into various Hornby and Bachmann diesels.

 

I must say all have been faultless, both control (once CVs have been fine tuned) and sound.

 

Except for just one, strangely a 31 as well which behaves eratically - sometimes it judders, other times smooth despite changing CV150 to 1.  I actually think it may be the loco mechanism needs servicing. Maybe a fine tune of the back emf CV as well.  Anyway, sorry, I'm going on about a minor problem which doesn't relate to your problem with the sound.

[Izzy]

No, it’s interesting to share views and problems for sometimes answers to these can arise in connection to other things. I have a lot of time for TTS because without these cheaper decoders many such as myself would have never tried sound. Often the experience in a home environment is quite different to at an exhibition. Indeed my view was that it was over-loud and invasive and I had been put off just going to exhibitions so fed up was I with the cacophony of noise too many ‘sound’ layouts together at full chat produced. 
 

Izzy

[cravensdmufan]

2 hours ago, Izzy said:

I have a lot of time for TTS because without these cheaper decoders many such as myself would have never tried sound.

I very much agree with that. 

 

Without the TTS decoders it would have taken me a few more years to sound fit my entire fleet.  I have combined what I consider the best of TTS sounds (fitted with upgraded speakers) with premium Loksounds and Zimos and am really delighted with them all.  And it all started with one loco with sound!  And of course once you have one, the others running around eerily silent don't seem quite right!

 

Some of my first generation DMUs are still without sound - I'm just awaiting on a sound expert to fine tune a couple of projects - and consequently it's only those four units are not run at present.

 

I never thought I'd be this happy with my model railways.  So much progress in the last 20 years - it's fantastic actually.  

Edited October 12, 2020 by cravensdmufan
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[Chrisr40]

Regards your dmu fleet cravensdmufan, I think generic  TTS dmu chips for heritage and modern variants would be a massive win  hint hint Hornby pretty please

[KDG]

30 minutes ago, Chrisr40 said:

Regards your dmu fleet cravensdmufan, I think generic  TTS dmu chips for heritage and modern variants would be a massive win  hint hint Hornby pretty please

I've  a small fleet of 101's, 153's, and 156's awaiting such tts chips.....

 

[DJDAVE]

Regarding the juddering class31. We fitted a TTS 31 chip into a full fat 31(ie not railroad) and it ran like a dog. The solution was we removed the capacitors from the motor and entered 1 on cv10. Runs as sweet as a nut now.

[Chrisr40]

1 hour ago, DJDAVE said:

Regarding the juddering class31. We fitted a TTS 31 chip into a full fat 31(ie not railroad) and it ran like a dog. The solution was we removed the capacitors from the motor and entered 1 on cv10. Runs as sweet as a nut now.

I had the same but only had to change the cv for motor control from 0 to 1 ? Did that not help on yours ?