creilly81

Just seen this - did you add a value of 16 to CV29 to enable the complex speed curve?

Not wishing to say the obvious, but have you checked the valve/motion gear to see if there is anything bent or catching?

As others have said, the current TTS decoders people have found to be pefectly adequate for what they require, however those wishing to invest a little into a speaker upgrade will get improved results. Just to go to the top end of that scale, i have a Hornby Class 66 fitted with TTS sound and i've upgraded the speaker set-up from the standard 40x20mm oblong type to an 4ohm EM2 Megabass speaker wired in series to a 27mm round 4ohm bass enhanced speaker to equal 8ohm. It now sounds incredible.... It depends what youwant to achieve i guess.

If this is a railroad model, can you check to see if indeed the tender has pick-ups as disconnecting it if it hasn't wouldn't change anything anyway. I'd be suprised if the tender does have them, that it should stall.

Something to clarify. The modification you made to the speaker wires- what modification was it and what did you do? I'm wondering,if you used a soldering iron - that there could be some solder cross contamination across the decoder PCB if you were anything other that precise.

Hi Ard, I had a similar issue - but not with TTS decoders. What was causing the problem for me, was how my layout was configured and wired up. Due to lack of space at home currently and with 2 kids under 5, I don’t have a dedicated room with a layout in at present, just an end to end shunting setup with 4 tracks on a 2m long window seal in the spare room. For ease and because it was a temp setup I used the Hornby clips to electrify all tracks - and didn’t have a dedicated bus feed, just connected at one source on track. Due to how this was set-up and configured it was causing random actions and conflicts with certain sound decoders - exactly as you have described. How is your layout wired up? Do you have a dedicated bus feed and rail droppers? How is the power supply feeding and connected to the track? It may help diagnosing the issue a little better as I'm not convinced the TTS decoder is the culprit..... Kind Regards Chris

It's actually worth noting that i have one of the latest Princess release's R3709 Princess Elizabeth which i also bought the relevant TTS sound decoder for, and fitted it with the standard 28mm round speaker without a problem. Providing you mount the speaker so that the wire contacts are shown in the cut out of the tender weight, and you pop a strip of insulation over the contacts before screwing the weight back down, it will fit perfectly - ample room in fact. I'd be interested to know how you tried to mount it and came to the conclusion it wouldn't fit without a major modification to the tender chassis....

The light has been wired to be on constant, whether in DC or DCC mode and if running forward or backwards. I hope this helps

Ally, Glad the Mallard is fixed - i was going to suggest a faulty speaker as it will crackle and volume reduce if it's on it's way out. The 66 - Can i ask, have you changed the speaker at all? I querying it as the results you describe i've seen happen when fitting a 4ohm speaker to a TTS chip - and obviously the TTS chip can only really run with an 8ohm speaker.

Hi John, Just an initial thought if you are able, could you place the loco on the programming track and read the value of CV7? Kind Regards Chris

All i would say regarding laying track for a DCC set-upand this is my personal preference (and of course this may also depend on the size of your layout) is to have your control wired to a main bus and have rail droppers every so often which are then soldered or wired to that bus. This creates a far more reliable connection all the way around your layout and leads to far less problems regarding DCC related locomotive issues. Pre-soldered fish plates made by Peco with dropper wires attached (i believe the part number is PL-80 if you are using the standard Hornby track) with colour corosponding red and black wires,which makes it easier to set-up.

Can i just check? Have you tried more than 1 loco - i'm assuming yes. If you haven't it could possibly be a duff decoder and so it's worth trying another loco... Otherwise it could be one of the solutions above!

It could also be dirty wheels, as they do cause extra drag. After reasonable running timeon the club layout (around 5 hours), my 6 Pullmans felt as though they had twice the running resistance as when i started. Cleaning each wheel to remove the carbon deposits solved the issue and they ran free again!

Hi, is it a latest edition Hornby castle class with the decoder socket in the tender or is the decoder in the loco? If its in the tender there will be an 8 pin socket in there which will accept an 8 pin plug. 😉

Exactly as i suspected, as have experienced the same trhing. Easy fix and glad it's sorted! 😉