essdee wrote:Hi Nigel,
I am extremely grateful for the time you have taken over this response - much appreciated.
The fact that the J15 was not supplied complete with Hornby's preferred chip is news to me! I exactly understand the range of problems that now presents in narrowing down the range of potential problems. I will check the loco's source with them, and then enquire from teh shop what would have been fitted.
Even if Hornby have a "preferred" chip, its probably something with a Hornby badge on the packet, and unlikely to be in the "superb" category.
My guess is a model shop fitted something either "poor" or "average" because it was cheaper than the alternatives, or came in a packet labelled "Hornby" or "Gaugemaster" (neither would make my recommended list for decoder badges).
If its a sound loco, then the sound could be one of the following:
Hornby TTS - cheap, known to have the odd running problem from some decoders (largely resolved, but old stock with faults still in circulation in shops), but Hornby will replace decoders which are defective in running.
ESU LokSound V4 - expensive (£100 or more), good quality. Sound quality depends on the sound files installed on the decoder (they can be indifferent, can be superb), choice of speaker, quality of speaker installation. Running issues may be decoder settings which an expert could resolve - the "Autotune" of motor settings is the usual place to start.
Zimo - fractionally cheaper than ESU, but only just. Also good quality. Sound quality also dependent on the quality of the installed sounds, and loudspeaker. But like the ESU a lot of settings to faff with if its not running well.
Then there are the less likely, but do exist options:
Soundtraxx - US maker, but has some UK options. Cheap, and sales in UK to UK outline are incredibly low.
Digitrax - ditto.
The potential mis-match of speed steps is something I can check on my next visit, many thanks for that tip. I see 28 should be the default, but it is possible that inexpert use of the hand set has somehow altered the setting to create a problem.
One option is probably for them/me to return the loco to the shop, and explain the intermittent running, in the hope they may be able to relate that to the chip they fitted (and indeed identify what chip that was, for me). Such trips have now become relatively major 'expeditions' for them, sadly.....
Chip identification is possible by reading CV's 8 and 7 (and then depending on the results, there might be others to read which will narrow the search space further). CV8 should reveal the manufacturer's code. CV7 is whatever version numbering the manufacturer uses (some are decent, others don't tell you much), and then the "others" are manufacturer specific.
Trouble with this is it rapidly gets quite technical (I'd do most of this stuff using a computer to read the values from the decoder), and you sound like you're near the limit of your knowledge without making matters harder.
Ironically, Tony chose to start afresh with DCC mainly for the sound effects etc, as well as the simpler wiring, but now struggles to utilise the function keys. This is such a cruel illness, and his frustration and disappointment are evident. Your suggestion of returning to conventional DC is very sensible, and I fear that I may be heading down that road for him before too long. But we will persevere a while longer.
My reason for suggesting DC is twofold:
In the absence of a local expert, the faffing necessary to resolve small running issues can be quite high, and beyond someone like Tony with serious muscle control issues. Sometimes the running issues can be mechanical, sometimes electronic (suppression devices) and sometimes settings inside decoders (CV values on keypads or computers).
Modifying a DC controller for easier control is probably simpler and less risky than modifying a DCC handset. For example, direction control could be a very long arm on a toggle switch, or a lever arm on a rotary switch. Speed control knob could be replaced with a bolt-on lever arm, etc.. The direction switch can be removed from the panel/handset and placed somewhere else, etc.. All wiring and mechanical changes which many modeller's won't struggle with.
Whereas, though its possible to chop up a DCC handset to replace knobs, switches, etc.. with larger ones which are easier to operate, its a much more daunting and technical proposition.
Another DCC system which might be easier on the hand-coordination may be a ZTC system. Bought new they are stupidly expensive for what they are, but Taunton Controls (current ZTC owner) have some s/hand 511 systems available for £210. Upside - large knobs to control things, "hewn from solid metal" feel. Downside of the 511 is that it's a very old design, doesn't do all the higher functions (some sound decoders have sounds on F18 or F27, etc..), but will do the lower functions. Its got various other quirks and faults which mean I'd rarely suggest one. But, in this case, its ability to work the control knobs which counts above all other factors, and it might work. Just maybe Taunton controls would let you have one on approval for the price of return postage ? You could ask them.
Alternative DCC approaches, and these are very "left field". I could expand on them if thought to be possible:
NCE PowerCab system plus a NCE MiniPanel, and use the input buttons (your choice of buttons, you make the control panel yourself) on the MiniPanel to control trains (eg. button 1 = "loco 57 go to speed step 15", etc). Might work if the three locos can be controlled with ten commands each (thirty buttons on a MiniPanel).
Sprog PI (a Sprog was originally a DCC "programming" device, but its now evolved into a small DCC system). This version connects to a £30 Raspberry PI, there is the potential for push button input via the GPIO pins on the PI to control things. Again technical/computer, but has potential to work.
Similar solution with push button panel possible with Digitrax system and a CML Electronics DS1 "shuttle" board.
Touch pad control (iPad or Android tablet) via Roco Z21 system.