Digitrax speed step jumps problem

Model Railroader Electronics and DCC
1

I run HO and use a Digitrax SEB, PR3 and JMRI to run the layout.

Problem I am having is when I run a pair of MRC Santa Fe F7’s (MRC deoders have been replaced with DH 123’s) and using the DT 400 throttle. When using the DT 400 when I advacnes the speed it jumps 6 steps at a time. When I use JMRI I get 1 speed step at a time? [^o)]

DH-123 Decoders are set for 128 steps so the problem should be in the DT 400. How do I clear the problem from the throttle or the DB150? There address use to show up on the DT 400 as 30 X 2. I use 30 as there address. Has not showen up that way for awhile now. Just show Loco 30 if that helps.

Thanks for the coming answers.

Cuda Ken

2

Ken,

The ‘system’ sends out 28 speed steps. The ‘decoder’ is capable of 128 speed steps. Your DT400 throttle only has 0-99 on the LCD panel. What happens is that decoder looks at the 28 speed step info and adjusts for 128 speed steps. When you use JMRI, it is displaying what speed step on that computerized screen you have selected. The DT400 is caught between 28 speed steps and 128 speed steps. I have noticed something similar as the throttle setting jumps as I dial up the encoder on my DT400’s. Maybe a sign of a bad encoder in the throttle? Or maybe a ‘rounding up’ error? The trains all run smooth so I really do not care. I have been using my cell phone as a throttle for the past 6-8 months, and really do not break out the DT400’s unless someone shows up with no throttle.

Jim

3

I seem to have this problem about once a year. I seem to always find the solution to setting the throttle back to the way it should be.

BUT!! I can not remember what it is I do to fix it as, I said it happens so seldom. I think it had something to do with a CV setting, but not sure.

Hope someone who has solved this has a better memory then mine. Will I remember to write down the solution next time? Naw!

4

At some point you have “status edited” that decoder address to 28 speed steps (told the command station that decoder uses 28 speed steps). To status edit it back to 128, while in the loco select mode with that address displayed, press ‘edit’, then turn the throttle knob to change back to 128 and press ‘enter’.

5

A tell tell for a wrong status on a decoder is a jump of 3 steps by 3 steps. In your case it is 6 steps which make me wonder what is the problem. However status editing the decoder can’t cause any harm.

I would go along with CSX Robert’s suggestion.

6

Oops, I did say 28 steps, but actually, when it is jumping 6 steps at a time then the decoder has been status edied to 14 speed steps.

7

Thanks for the precision CSX Robert.

8

CSX Roberts, that took care of the problem! [Y] Thank to all that tried to help.

Cuda Ken