# 28 vs 128 speed steps and what is better?



## tkruger (Jan 18, 2009)

I have an NCE Power Cab starter system and so far really like it. By default is uses 28 speed steps. I have not yet tried 128 steps. What is the difference, and why choose 28 or 128? With the exception of one Athearn Genesis locomotive everything else I have is converted BB, Riverossi, Mantua, Bachmann Spectrun, Proto 2000 etc. I have used NCE or DigitTrax decoders for all but one.


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## Brakeman Jake (Mar 8, 2009)

While both minimum and maximum speeds are the same,one will give you more "clicks" within the range wich allows finer throttle settings.Both settings will work and the difference may be irrelevant to many.

I understand most are using 128 steps.It allows finer tuning for speed matching consists for instance.Wichever protocol you choose will work but you have to make sure that both your command station and your decoders (CV29) are set to the same protocol or you will have occasional weird behaviours from your engines.There are known issues with sound decoders if both don't speak the same digital language.


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## DonR (Oct 18, 2012)

The two latest Digitrax decoders that I have installed apparently
are set for the 28 steps. There is a decided 'jump' from one speed
to the next when starting out. My Bachmann EZ DCC controller does not have
the capability of setting CVs so I must wait til I can collar an
NCE or Digitrax operator to do that for me.

Don


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## CTValleyRR (Jul 26, 2014)

My MRC Prodigy Wireless switches back and forth at the touch of a button. Most of the time, though, I just leave mine in 28 steps. That's enough granularity for me. In 28 step mode, I change the throttle 1 or 2 clicks at a time. When I go to 128, I always find myself moving several steps at a time.

Many prototype diesels have 8 notches for the throttle setting and you have to jockey that back and forth with lapped brakes to maintain a given speed. Constant throttle adjustments to maintain speed is part of railroading.


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## mesenteria (Oct 29, 2015)

The voltage differences between each of 28 speed steps is more discrete than it is between a lot more speed step, the 128. If you had a construction square and ruler with only inch markings, and not the usual 1/16th inch marks, it would require some error and guessing to mark the half inches. Similarly, setting a decoder to run on 128 speed steps gives you finer control over your speed because instead of, say, 1/4 volt between speed steps numbering only 28, with the resultant noticeably and immediate change in speed (not very realistic). Instead, you might only get 1/10th of a volt rise, so that, when you instruct the decoder to parcel that voltage to the motor, you'll not really notice it. Yet, the locomotive will speed up marginally.

I think many people just end up running on 28 speed steps by default as they don't really notice the speed change all that much, if at all. Try it yourself; you will probably be quite happy, as most are. If you wish finer control, simply configure your decoder to do that.


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