bandmjim,
As stated above, I am unable to read the CV 29 value (the throttle display shows a blinking "29" as the data reading). I changed CV 29 to "2" and the loco operates the same way it did with the previous default CV 29 value ("6" after I reset the decoder to factory defaults) w/the stopping issue when running @ 128 speed steps. I also adjusted the Acc & Dec CV values, but it still starts & stops jerkier than I would like. This is something of a puzzle and so far I'm missing still a piece......
Thanks,
akriggm
Ok, leave cv29 at 2, set speed step to 28 setting not 128. set cv's 2-5 & 6 as before, and set cv's 3 & 4 to a value of 30 each see what that does, then try 40 each and see. I don't use cv 3 and 4 so just going by what others have tried. Are you using the program track, right, does the loco sound come on while programming these cv's or reading them?
Even more strange that is is worse with 128 - I've NEVER seen anything run smoother with 28 than it does with 128, simply because with 128, each step is a smaller percentage of the range, so each increment is that much finer. There is in general no other decoder change for 28 or 128 steps, it's just a different packet format sent by the command station.
It's possible there is still some CV set in an odd way, especailly since the decoder does not appear to be properly resetting other common CVs to default values properly.
One thing that always improves a Bachmann loco with DCC (and some kinds of DC controls even) is to remove the completely unecessary capacitors they put on the motor terminals. Sometime these are right on the motr itself - in which case it is absolutely safe to just cut them off. Other times they are on the circuit board (not the decoder, the lighting board it connects to) in which case you need to carefully make sure you are removing the right thing. They interfere with the motor drive signal from the decoder and can cause jerky operation.
There are some other motor Fine tunings you can do in the decoder, the SoundValue versions are limited compared to a full Tsunami but there are some settings, if the only issue now is jerky motion. But also make sure there is no mechanical issue, because no amount of decoder fiddling will correct an out of quarter driver or other bind int he mechanism.
--Randy
Modeling the Reading Railroad in the 1950's
Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.
Randy,
Actually the loco runs noticably smoother at 128 than at 28, but it won't stop when the throttle is reduced to "0" in forward; it just keeps rolling along at speed "1" until the emergency stop (red) button is pushed. It has normal stopping behavior in reverse. Setting the speed steps to 28 (or 14) eliminates the problem, but reduces the smoothness of speed changes as you mentioned. I've adjusted the momentum CVs which helps a little, but I'd still like to get this sorted out so I can go back to running this loco at 128 speed steps.
Here's a link about clipping the capacitors mentioned earlier - I couldn't find one specifically about the 4-4-0, but I think the boards are all pretty much the same.
http://tcsdcc.com/installation/ho-scale/bachmann-spectrum-usra-light-2-10-2/t1p-sh
Re CV29 default, it appears that if your engine is an older one with a Soundtraxx SoundValue decoder, default is 06. If it's a newer one with the Soundtraxx Economi, the default value is 02. Either way, Soundtraxx website has a big chart showing what each entry into CV29 does for each of the decoders.
BTW if you do open up the tender, you could try unplugging the sound decoder and temporarily plug in a different decoder, and see how that responds.
Plus, I'd still be interested to know (since it apparently worked OK before you changed the ID from 03 to 106) if ID 106 is the only problem. I'd try changing the ID to 100 or 99 or something and see if it works right then. If only ID 106 is affected, then there's something going on like ID 106 is part of an old consist or something.