TTS Sound Class 20

[RAF96]

Can I just make a small correction to the above.

Swapping red for black (track connections) will not affect anything, you need to swap orange and grey (motor connections as said in text). The CV29 route is more sensible as it doesn't take a loco away from standard wiring convention.

 

TTS - I could rail on for pages about the slightly incorrect previous comments and assumptions but I won't, apart from to say that Hornby along with other DCC manufacturers realise that over prompt accordance with NMRA standards and recommended practices can introduce problems resulting in kit having to be retro engineered to the previous standard to correct the problems.

 

DCC is a bit like other electronic standards, such as bluetooth and WiFi and those infernal mains internet powerline adaptors. They all accord with a standard but you try and get them all to play nice together and that's another matter at times.

 

Going back to the Class 20 nose to nose problem. Providing there are no lights fitted then the reversed plug idea will work, as will the swapped motor leads. I have no idea which pcb if any is fitted to these Class 20 but reversing the plug could damage the decoder if lights are catered for on the board and depending upon their integration.

 

There was talk on one forum where you could fudge a consist orientation by adding 128 to the value of a particular CV (28 or 19 I can't remember and I can't find the particular thread again either) for the loco that you wanted to reverse control, but at the time of posting there was no proof of this working. Hornby's Railmaster has a tick box in their Pro-Pack version which allows a nose to nose configuration so it can easily be done.

Edit - NMRA shows adding 128 to value of CV19 will reverse a loco direction in a double,header.

 

I can confirm though that if you consist TTS decoders within the Hornby system then you can control the speed and direction as a consist but each locos,sound functionscan be controlled separately, e.g. separate engine starts, horns and lights, etc. Whether other DCC controllers arrange their consists in this manner is within their control not Hornby's although I would suggest some collaboration of effort twixt manufacturers to assure fuller DCC accord would be sensible if it could be done within the trust of one company not transgressing another's IPR.

Rob

Edited September 6, 2017 by RAFHAAA96

[SDJR7F88]

Hi all, had another attempt this morning with the same result, so took one of the 20's apart and reversed the plug. And it works a dream!

Was surprisingly easy to get into the 20, remove the buffers then lift the body off. Popped the plug out, turned 180 and replaced. Plenty of room in the body for the wires. As there are no lights, there no problem regarding that issue, will keep my fingers crossed regarding the PCB, though there seemed to be no trouble after 5 minutes of running.  

Once happy I then tested it with the other 20 and they runs as a pair very well (though I note which ever 20 is going nose first it then's to be a tiny bit quicker, though not by much). The sound of both running together is superb!  

Plan to renumber one at some point to a fellow class member at a later date. Seen a few pictures of 20163 paired with with 20170 so might recreate her. 

Will post a video of the pair in action soon, once a bit more testing has been carried out 

 

Once again thanks for all the help! Sure I will get the hang of all the codes and numbers people keep mentioning at some point 

[John Tomlinson]

Callum,

 

Really glad you've raised this as I've been playing with my two TTS 31's and encountered similar issues, and am equally new to DCC.

 

Great to know it wasn't just me, and huge thanks to Paul, Charlie and Rob for their very informative responses.

 

John.

[meatloaf]

Has anyone transplanted the decoder and speaker to a Bachmann class 20?

[SDJR7F88]

Finally got around to filming a little video of my pair in action. Must say I really love the Thrash button! 

 

http://www.youtube.com/watch?v=jFocsCWSUt4

Edited September 5, 2017 by SDJR7F88

[pauliebanger]

Great.

 

Well shot video and controlled sounds.

 

They run and sound really good. Thrash eh? That sounds like fun.

 

Kind regards,

 

Paul

[Robby S]

I've made a comment in the DCC questions area in a topic about ECoS, but feel I should note it here as well. The class 20TTS works correctly on Hornby controllers but once you change number from 3, then using most other controllers such as Roco Z21, Sprog, ECoS and Bachmann it only seems to work correctly when facing one way but turn the loco round on the track and it's dead. A real puzzle!

[SDJR7F88]

I've made a comment in the DCC questions area in a topic about ECoS, but feel I should note it here as well. The class 20TTS works correctly on Hornby controllers but once you change number from 3, then using most other controllers such as Roco Z21, Sprog, ECoS and Bachmann it only seems to work correctly when facing one way but turn the loco round on the track and it's dead. A real puzzle!

So same as the 31? Not had an issue with mine so far. Though they will only run one why if you try and change the direction setting (so to get them nose to nose)

[brammie]

Here's hoping: I have two Class 20 diesel locos which I intend to run in consist. One is an out-of-the-box Hornby with TTS fitted, the other is a Lima which previously ran extremely well on a Lenz chip and which continues to run extremely well with a Hornby TTS chip fitted. Both work fine individually on my ECoS controller. My problem is the difference in their speed for specific throttle settings. On test track with both locos selected on the ECoS screen the Hornby runs approx 25% faster (in either direction) than the Lima for the same throttle setting. I have been assuming that this can be dressed out by speed matching through CV settings, but I can't find any simple process by which to achieve this. I am sure that this problem is not unique to my locos, so would greatly appreciate any advice from others who may have encountered a similar problem. 

 

Brammie

Edited August 10, 2018 by brammie

[SRman]

Speed matching really is a matter of trial and error. Changing the settings on CVs 5 (Max voltage/speed) and 6 (mid-voltage/speed) in increments before refining further with smaller step changes until the two locos are running, accelerating (CV3) and decelerating (CV4) at very similar rates.

I'm not sure if the TTS decoders support speed tables, but those would allow even more finesse in matching the speeds at different speed steps, but will be even more tedious to set up. In the long term, the effort involved is worth it, though. I recently had to match two Hornby 4 VEP units, and even with both having Lenz Standard decoders fitted, I had to alter CVs 5 and 6 on one of them to get them to run in a consist reliably.

[cravensdmufan]

Has anyone been able to do an advance consist with TTS decoders?

 

With NCE Powercab my pair of Bachmann 20's with TTS will only accept  an "old style" consist which means 28 speed steps only.

 

So to get better control I had to resort to programming both locos with the same address.  Which works fine as I have them semi permanently coupled nose to nose by means of a Bachmann DMU coupling bar.  But ideally I'd like separate addresses for the locos.

 

Would be grateful for any advice.

[RAF96]

The only useful TTS consist I have seen is in Hornby’s Railmaster which allows two locos to be lashed together for motor control but their sound controls remain separate, so you can toot individual horns, etc.

 

Edit - That apparently is done in the software and not within the loco decoders.

Rob

Edited August 10, 2018 by RAFHAAA96

[brammie]

Speed matching really is a matter of trial and error. Changing the settings on CVs 5 (Max voltage/speed) and 6 (mid-voltage/speed) in increments before refining further with smaller step changes until the two locos are running, accelerating (CV3) and decelerating (CV4) at very similar rates.

 

I'm not sure if the TTS decoders support speed tables, but those would allow even more finesse in matching the speeds at different speed steps, but will be even more tedious to set up. In the long term, the effort involved is worth it, though. I recently had to match two Hornby 4 VEP units, and even with both having Lenz Standard decoders fitted, I had to alter CVs 5 and 6 on one of them to get them to run in a consist reliably.

Thank you for that SRman. I wish it were that simple; neither CV5 nor CV6 are listed in the Hornby Class 20 Sound Decoder Manual, and reading them on the ECoS Controller shows "Error" for both CVs. There is however reference  to "CV150-154: Motor Control Method", the lengthy explanation of which seems to imply that motor speed control is achieved through compensation under load - as opposed to setting loco speed for a specifc throttle setting (which is a must for two locos in consist).

[SRman]

Thank you for that SRman. I wish it were that simple; neither CV5 nor CV6 are listed in the Hornby Class 20 Sound Decoder Manual, and reading them on the ECoS Controller shows "Error" for both CVs. There is however reference  to "CV150-154: Motor Control Method", the lengthy explanation of which seems to imply that motor speed control is achieved through compensation under load - as opposed to setting loco speed for a specifc throttle setting (which is a must for two locos in consist).

 

That's a bit unfortunate. I haven't really explored the TTS decoders I own at all as both are used singly (i.e. they are never required to be in consists or multiples). One is a class 37, installed in a ViTrains example (I sold the Hornby donor off), and the other is a steam one from a Merchant Navy that I thought didn't suit the MN at all, sound-wise, so swapped it into a Standard class 4.

 

All other sound decoders I own are either ESU LokSounds or Zimo MX series.

[brammie]

Following advice from a member on another site, I attempted to speed match my Lima Class 20 loco fitted with a Lenz decoder to the Hornby Class 20 with TTS sound. I spent a day trying to rig the CVs, and finally settled for something workable but not ideal. I then added a Hornby TTS decoder in the Lima, wired up only to the wheel pickups (black and red) for supply and only speaker outputs connected. Whilst the loco was happy to run well under the control of the Lenz decoder, it was clear from my ECoS dispay that all was not well. Ordinarilly, each of the (20 plus)TTS sound functions is represented by a symbol on the ECoS controller, but in this case - nothing. I checked out wiring, again, and was left scratching my head, but was left wondering whether red and black only to the Hornby TTS decoder are sufficient.

 

Whilst walking my dog this morning, the thought occured to me that I might rig the Lima Class 20 with a Hornby Class 20 TTS decoder again, but this time insert a dropper resistance in series with the motor connections to reduce the motor speed to that of the Hornby Class 20 for the same throttle setting. At a guess, I could start with 4ohm, 4watt (max motor current 1 amp) and then replace with higher/lower R value to achieve speed matching of the two locos at cruising speed. If that idea worked, I could then set the two locos up to run in consist, as per the ECoS manual. Anyone see any obvious problems with the idea?

[JSpencer]

Following advice from a member on another site, I attempted to speed match my Lima Class 20 loco fitted with a Lenz decoder to the Hornby Class 20 with TTS sound. I spent a day trying to rig the CVs, and finally settled for something workable but not ideal. I then added a Hornby TTS decoder in the Lima, wired up only to the wheel pickups (black and red) for supply and only speaker outputs connected. Whilst the loco was happy to run well under the control of the Lenz decoder, it was clear from my ECoS dispay that all was not well. Ordinarilly, each of the (20 plus)TTS sound functions is represented by a symbol on the ECoS controller, but in this case - nothing. I checked out wiring, again, and was left scratching my head, but was left wondering whether red and black only to the Hornby TTS decoder are sufficient.

 

Whilst walking my dog this morning, the thought occured to me that I might rig the Lima Class 20 with a Hornby Class 20 TTS decoder again, but this time insert a dropper resistance in series with the motor connections to reduce the motor speed to that of the Hornby Class 20 for the same throttle setting. At a guess, I could start with 4ohm, 4watt (max motor current 1 amp) and then replace with higher/lower R value to achieve speed matching of the two locos at cruising speed. If that idea worked, I could then set the two locos up to run in consist, as per the ECoS manual. Anyone see any obvious problems with the idea?

Do they both have traction tyres? If one is with and one without, that could make a real big difference in how the locos perform.

[Izzy]

Following advice from a member on another site, I attempted to speed match my Lima Class 20 loco fitted with a Lenz decoder to the Hornby Class 20 with TTS sound. I spent a day trying to rig the CVs, and finally settled for something workable but not ideal. I then added a Hornby TTS decoder in the Lima, wired up only to the wheel pickups (black and red) for supply and only speaker outputs connected. Whilst the loco was happy to run well under the control of the Lenz decoder, it was clear from my ECoS dispay that all was not well. Ordinarilly, each of the (20 plus)TTS sound functions is represented by a symbol on the ECoS controller, but in this case - nothing. I checked out wiring, again, and was left scratching my head, but was left wondering whether red and black only to the Hornby TTS decoder are sufficient.

 

Whilst walking my dog this morning, the thought occured to me that I might rig the Lima Class 20 with a Hornby Class 20 TTS decoder again, but this time insert a dropper resistance in series with the motor connections to reduce the motor speed to that of the Hornby Class 20 for the same throttle setting. At a guess, I could start with 4ohm, 4watt (max motor current 1 amp) and then replace with higher/lower R value to achieve speed matching of the two locos at cruising speed. If that idea worked, I could then set the two locos up to run in consist, as per the ECoS manual. Anyone see any obvious problems with the idea?

 

Having 'piggybacked' a 31 TTS decoder like this with a Zimo MX600 which works well there are a couple of points that come to mind. The first is, are you using the same address for both decoders? This is pretty essential to get them working in unison. I am sure you have, but still worth asking. Next up is, I wonder if the same firmware issues exist with your particular decoder as affected the 31's, i.e. on certain DCC systems they will only respond when in one particular direction. If this is the case then you might just try turning the loco around, or if you want it running in a particular direction, reverse the black and red wires connections.  These are all the connections you should need, no others are neccesary. Indeed you should be able to just hook these wires up directly to the rails - no loco needed !  - and get the TTS sound chip to work. This is how it is possible to use them as function only sound decoders. ( I assume the amplifier/speaker is the load). Perhaps you could try this first to determine whether the decoder works either way around on your ECoS system.

 

If none of these work I can only think that somehow there is a compatibility issue with the ECoS. I have no experience of this system, using a Prodigy PA2, but perhaps it can't 'see' both decoders at the same time if they have the same address. It's all I can think.

 

Izzy

[brammie]

Do they both have traction tyres? If one is with and one without, that could make a real big difference in how the locos perform.

 

JSpencer: The Hornby driving wheel bogy has traction tyres on a single (opposing) wheel of each axle only .The Lima Class 20, as is generally well known, has traction tyres on all four driving wheels. Thank you for your interest. I am currently banking on the in-line resistor plan to reduce motor voltage output from the decoder.

[brammie]

Having 'piggybacked' a 31 TTS decoder like this with a Zimo MX600 which works well there are a couple of points that come to mind. The first is, are you using the same address for both decoders? This is pretty essential to get them working in unison. I am sure you have, but still worth asking. Next up is, I wonder if the same firmware issues exist with your particular decoder as affected the 31's, i.e. on certain DCC systems they will only respond when in one particular direction. If this is the case then you might just try turning the loco around, or if you want it running in a particular direction, reverse the black and red wires connections.  These are all the connections you should need, no others are neccesary. Indeed you should be able to just hook these wires up directly to the rails - no loco needed !  - and get the TTS sound chip to work. This is how it is possible to use them as function only sound decoders. ( I assume the amplifier/speaker is the load). Perhaps you could try this first to determine whether the decoder works either way around on your ECoS system.

 

If none of these work I can only think that somehow there is a compatibility issue with the ECoS. I have no experience of this system, using a Prodigy PA2, but perhaps it can't 'see' both decoders at the same time if they have the same address. It's all I can think.

 

Izzy

Thank you for your interest Izzy.

 

Firstly, to answer your questions, (1) Yes, the same address loaded in each decoder. (2) The LIma Class 20, when previously fitted with a Hornby TTS only, ran happily with the nose pointing in either direction.

 

I spent the afternoon removing the Lenz decoder from the Lima Class 20 and reconnecting the Hornby TTS wires left unconnected. It runs perfectly again, with all sound functions also working perfectly. As a matter of interest, I fitted the Lenz decoder to a second Lima Class 20 chassis that I own, and it runs pretty well in that. Testing the Hornby Class 20 together with the Lima Class 20, both with TTS decoders (but not in consist) shows the Lima to run some 20% faster than the Hornby for the same throttle setting. The next initiative is to install a small resistor in line with the Lima motor connections to reduce the voltage, and so the speed. I will start with a 4ohm 4 watt and take it from there. One good thing came out of the exercise; what a belter to hear two Class 20 locos giving it out from their speakers!

[Izzy]

 

Glad to find your getting there. I remain puzzled as to why the TTS couldn’t be piggybacked, perhaps the answer will be found someday. It is awkward that there is no way of altering the basic TTS speed, leaving no alternative but that which you are trying.

 

Izzy

[JSpencer]

Glad to find your getting there. I remain puzzled as to why the TTS couldn’t be piggybacked, perhaps the answer will be found someday. It is awkward that there is no way of altering the basic TTS speed, leaving no alternative but that which you are trying.

 

Izzy

 

On TTS there are normally 28 speed steps split across  256 speed values in CVs 64 to 97 (or there abouts) and they can be adjusted. However low values are already low by default, so you can only up the Hornby class 20 ones.

That said, my thoughts would be a resister first, the Lima 20 can run like a bat out of hell. When I worked at the Signalbox in the 90s, we used to get the odd return on this model whereby people would treat them like a racing car with sudden acceleration and braking, the poor shaft could not take it and sheared....

Edited August 27, 2018 by JSpencer

[brammie]

On TTS there are normally 28 speed steps split across  256 speed values in CVs 64 to 97 (or there abouts) and they can be adjusted. However low values are already low by default, so you can only up the Hornby class 20 ones.

That said, my thoughts would be a resister first, the Lima 20 can run like a bat out of hell. When I worked at the Signalbox in the 90s, we used to get the odd return on this model whereby people would treat them like a racing car with sudden acceleration and braking, the poor shaft could not take it and sheared....

Other than for trade, the UK supply of small value resistors is quite limited - but I have ordered a number of 4 ohm and 5 ohm, both 5 watt. Once to hand, I can try various combinations in parallel and in series in the hope of getting that Lima speed fixation under some sort of control!

[brammie]

Other than for trade, the UK supply of small value resistors is quite limited - but I have ordered a number of 4 ohm and 5 ohm, both 5 watt. Once to hand, I can try various combinations in parallel and in series in the hope of getting that Lima speed fixation under some sort of control!

Just had notification from Amazon that delivery forecast as 22 Sep! The items were listed as "In Stock", but I now see that the small print identifies source a HK!

[JSpencer]

Just had notification from Amazon that delivery forecast as 22 Sep! The items were listed as "In Stock", but I now see that the small print identifies source a HK!

 

Amazons new feature hiding the source location of the item is indeed annoying. A few toy items I ordered for my daughter over the past year gave no hint of where it was coming from, only to find it came from Asia, was not CE compliant and so on.

[Izzy]

On TTS there are normally 28 speed steps split across  256 speed values in CVs 64 to 97 (or there abouts) and they can be adjusted. However low values are already low by default, so you can only up the Hornby class 20 ones.

That said, my thoughts would be a resister first, the Lima 20 can run like a bat out of hell. When I worked at the Signalbox in the 90s, we used to get the odd return on this model whereby people would treat them like a racing car with sudden acceleration and braking, the poor shaft could not take it and sheared....

 

I don't know whether the diesel stand alone TTS are different, but the class 31's I have don't have any speed adjustment at all past the motor control and acc/dec. The cv's just don't exist according to the interrogation of the decoders via JMRI/decoder pro.

 

Izzy