Robby S

I had a similar problem with the GM500 with lots of head scratching until in desperation I read the instructions. The GM500 has to be wired to the solenoid with the common wire ( to the single solder pad ) negative polarity and the two other solder pads positive, whilst the solenoid works either way round ( i.e. it doesn't matter which wires are connected to positive/negative ). My GM500 wouldn't work until I changed the output wires on the CDU around and it then worked fine, but that was only using a two point crossover without any diodes. I found that my Gaugemaster CDU was only really reliable switching 3 Peco solenoids together ( I guess that with 2 three way points you need to change 4 solenoids together ), although changing to a 24 volt transformer ( intended for Christmas tree lights ) meant that 4 could now be moved together, but the small extra current needed to switch the GM500s at the same time lead to it becoming unreliable. As my layout is DCC I've dumped the GM500s and changed to Gaugemaster DCC80 Autofrogs that are powered from the DCC bus not the CDU and all is fine again. As an aside, our 00 club layout uses very old DCC Concepts boards to switch Peco solenoids ( they're not actually DCC but use 12v dc power ) with Peco switches mounted on the solenoids for the frogs. As many people have commented the Peco switches are not the most reliable so I tried to use GM500s instead. They wouldn't work so back to the instructions; found out that the boards/solenoids were correctly wired common positive and as the GM500 has to be wired common negative there was no chance of it working.

I have added DCC decoders to 2 Hornby DVTs, Wrexham and EWS.They have LEDs. The DVT has an 8 pin socket that I think is reverse wired - i.e. white lights on yellow wire and red lights on white wire so that it shows correct lights for rear of train. You will need to replace cover plug with a decoder ( last time I looked a function only decoder was as expensive as a standard one ). Any 8 pin decoder should do as they all seem to give 100 milliamps on function outputs.. As I use the DVTs with Hornby class 67s and run them as a unit train, I chipped both the class 67 and DVT and programmed them together so that they both had the same number. If you want to use a single DVT with 2 or more different locos I think you will have to program the locos and DVTs separately with different numbers then consist the DVT with each loco. A simple solution is just to take the cover plug out of the socket in the DVT and not bother with a decoder. Of course the lights won't work but you can use it with any loco. Anyone got any other ideas on how to use a DVT with more than 1 loco. I've also chipped several Bachmann class 158s, both 2 and 3 coach units.They have quite large LEDs and I think the resistors are about 1k so work fine. If you think the LEDs are too bright then you could try a higher rated resistor, but I didn't bother. Don't forget that you need a decoder for each coach and they need hard wiring.You can get away with only using 1 decoder per unit and wiring through between coaches using mini connectors. I tried this but thought it a lot of work just to save the cost of a decoder. Again I put the DMU unit on the programming track and programmed the decoders together, so that they all have the same number. I think only the Bachmann class 170s have bulbs, 158s 166s and 220s have LEDs. Look at Bromsgrove Models web site for detailed instructions for adding decoders.

I had same problems with Class 20 and Class 31 TTS decoders on my Roco Z21. Piggy backing didn't work. Phoned Hornby customer care, returned chips, came back after a week and both are now working fine. According to Hornby it's mainly some, but not all, of the class 31 separate chips as well as some ready fitted locos. Said new batch of decoders for 31, 37, 47, 60, and 67 should all be ok. Well we'll see soon!

There have been a lot of comments about problems with TTS chips.Several ready fitted locos have had problems. I bought R3394TTS class 20 and separate class 31 TTS and neither worked correctly: they only worked one way round. Phoned Hornby customer care, sent them back, Hornby reprogrammed them and a week later I now have two functioning locos. I also bought A1/A3 TTS for Flying Scotsman and this works fine. Maybe it's only the class 31TTS of the separate decoders that has problems ?

Sounds a good idea about piggybacking. I'll try it out. All my locos already have decoders fitted already and I was wondering what to do with removed ones. I've tried several controllers with new TTS decoders. As far as I can tell all controllers seem to initially program correctly but don't run the same. Hornby and NCE powercab run locos correctly even if number has been changed on different system. Roco, Sprog and Lenz and others will only work if loco is one way round, but it won't program; turn loco around and it doesn't respond at all to throttle, but it will program. Hornby should have made sure that they will work on all systems. I've noticed that Hornby don't mention NMRA compatibility in the instruction leaflet at all ( except when describing the 8 pin socket ).

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 31TTS decoder that's sold separately 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!

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!

Having programmed numbers of class 20TTS and railroad class 31 with TTS chip on Sprog and JMRI and they only work one way round, I put on elink and Railmaster and they work fine both way round without any reprogramming. I guess Hornby only checked that new TTS decoders worked on their own systems. Any ideas?

I've had exactly the same problem programming TTS 31 andTTS 20 decoders using Sprog and JMRI, also with my Roco Z21. Looks like they only programme with Hornby controllers? Has anyone successfully programmed them with any other make of controller? Its not too bad with a diesel as it doesn't matter too much which way round they are, but I hesitate to try to programme the TTS A1/A3 chip I've bought, as it would have to spend half its time running backwards.

Yes 3-way points do save a lot of space, but I would only use them where there is no other choice. We have used them on our club layout ( Wyre Forest MRC ) especially in the storage yard to gain a bit of extra track length plus 1 in the front yard. I don't think they are quite as reliable as two separate points. They also caused difficulties when wiring up LEDs for track diagrams where you only want 1 LED out of 3 on at a time. Extra ordinary diodes were needed and it took a bit of head scratching before we worked it out.