NCE version 23 (2.3?) decoder

[chessiesd35]

I'm having a problem with a recently purchase deoder installed in an older Atlas GP40. The engine is the newer Atlas version produced before the Master line came out. I've been running it by itself until just recently when I consisted it with another unit of the same vintage. This other unit has a Digitrax decoder. My unit has an NCE Version 23 (2.3?) decoder. I can't read the cv's for the speed steps. This unit runs considerably slower than the Digitrax unit. THe digitrax unit has all of the speed step registers set to 0 so to my understanding the spped cannot be lowered. Is the NCE unit (it has blue tape around it) and older version that doesn't support changing the speed steps ?

[cacole]

Are you sure about the brand name of the decoder?   I don't recall NCE ever using blue shrink wrap around their decoders.  Some had black wrap and some had clear, but most were bare.  TCS and Digitrax both used blue wrap.

NCE's document archives show no decoders with software version 2.3.

 

[rrinker]

 By 'speed steps' do you mean the 28 step speed table? These values will only do anything if you have CV29 set to actually use the speed table. If you mean CV2, 5, and 6, then all 0's means they aren't being used.

 What sort of loco is the Digitrax decoder in? And which Digitrax decoder? If it's one with BEMF t may not be turned on, you may get a lower starting speed from that. But DCC can't 'fix' a loco that doesn't already run slow. If you've tried adjustments to get it to run slower and it is now running at the slowest reliable speed on speed step 1 then the only thing you cna do to match another loco is speed it up. Start with CV2, start speed, and bump up the slower loco until it starts the same. Then adjust CV5 for the top speed - here you slow down the faster one to match the slower one. It might now be fine, but you can also adjust CV6 at mid throttle for both. This usually gets a close enough speed matching, the two locos don;t have to be dead on at every speed step to work well together.

                              --Randy