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Best way to adjust DCC loco movement for a lower speedstep.....

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  • Member since
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Posted by richhotrain on Saturday, March 3, 2012 4:34 AM

CSX Robert

 richhotrain:

I should consider going to the 128 setting.  The first DCC loco that I bought was set to 28 speed steps and I never thought about changing.

Rich

 

You do not have to change any settings in the decoder to use 128 speed steps, you only have to set the command station to send 128 speed step commands.  14 and 28 speed step commands "look" the same to the decoder, so when using one of them the decoder has to know which one you are using (hence the 28 speed step bit of CV29).  The 128 speed step command "looks" completely different from the other two and the the decoder will know that you are using 128 speed step commands without you changing any of it's settings.

CSX,

That's a good point, and let me elaborate. 

I use the NCE PH-Pro.  On the Pro Cab throttle, the speed step button is near the bottom of the throttle.  You press the button repeatedly to toggle between 28 speed steps and 128 speed steps.

It is also interesting to note that the speed step settings on decoders are controlled by CV29.  You either select 14 speed steps or 28/128 speed steps, not 14 or 28 or 128.

Rich

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Posted by CSX Robert on Friday, March 2, 2012 8:27 PM

richhotrain

I should consider going to the 128 setting.  The first DCC loco that I bought was set to 28 speed steps and I never thought about changing.

Rich

You do not have to change any settings in the decoder to use 128 speed steps, you only have to set the command station to send 128 speed step commands.  14 and 28 speed step commands "look" the same to the decoder, so when using one of them the decoder has to know which one you are using (hence the 28 speed step bit of CV29).  The 128 speed step command "looks" completely different from the other two and the the decoder will know that you are using 128 speed step commands without you changing any of it's settings.

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Posted by richhotrain on Friday, March 2, 2012 3:09 PM

I should consider going to the 128 setting.  The first DCC loco that I bought was set to 28 speed steps and I never thought about changing.

Rich

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Posted by rrinker on Friday, March 2, 2012 2:19 PM

 I guess I never think about it - Digitrax defaults to 128SS and I've never considered changing to a lower setting.

             --Randy

 


Modeling the Reading Railroad in the 1950's

 

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Posted by richhotrain on Friday, March 2, 2012 7:46 AM

rrinker

 STep 20 for a non-BEMF decoder isn;t all that crazy.

It is if you are running 28 speed steps instead of 128 speed steps.

But the OP says that he is running 128 speed steps.

Rich

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Posted by rrinker on Friday, March 2, 2012 6:51 AM

 STep 20 for a non-BEMF decoder isn;t all that crazy. Sometimes AThearn Blue Box locos with the stock motor won;t go until even higher speed steps by default, but that's what CV2 is all about.

              --Randy


Modeling the Reading Railroad in the 1950's

 

Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.

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Posted by mobilman44 on Friday, March 2, 2012 6:16 AM

Hi!

Yes, I did cut out the capacitors - which as I recall was suggested on the decoder instructions or in a tip from "Tony's Trains".

ENJOY  !

 

Mobilman44

 

Living in southeast Texas, formerly modeling the "postwar" Santa Fe and Illinois Central 

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Posted by farrellaa on Thursday, March 1, 2012 10:33 PM

No one has mentioned the Capacitors in the Spectrum locos; I have been told to cut them off or cut one of the wire legs to remove them from the circuit as it improves slow speed operation.

     -Bob

Life is what happens while you are making other plans!

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Posted by tstage on Wednesday, February 29, 2012 12:57 PM

mobilman44

Hi!

Adjusted the two Spectrum (HO) 2-8-0s start speed successfully.   Had to code in a value of 17 on one and 30 on the other.   Neither of these locos have seen much run time, and I suspect they will loosen up a bit once they are fully broken in.

When you achieve the results that you're looking for, Bill, you may want to jot those values down and keep them on file (or store them in Decoder Pro) - i.e. if and when you need to perform a reset.  Better than trying to remember...

Tom

https://tstage9.wixsite.com/nyc-modeling

Time...It marches on...without ever turning around to see if anyone is even keeping in step.

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Posted by mobilman44 on Wednesday, February 29, 2012 11:55 AM

Hi!

Adjusted the two Spectrum (HO) 2-8-0s start speed successfully.   Had to code in a value of 17 on one and 30 on the other.   Neither of these locos have seen much run time, and I suspect they will loosen up a bit once they are fully broken in.

Believe me, I did a LOT of research before I went to DCC 3 years ago, and went into it with my eyes open - knowing full well it was not a "plug and play" situation for me in any way.   Having said that, I also realized one could make DCC as easy or as complicated as one wants.  

The continuous learning and occasional frustrations are part of the game for me, and as we used to say at Mobil Oil, these are more like "challenges and opportunities"!

ENJOY!

Mobilman44

ENJOY  !

 

Mobilman44

 

Living in southeast Texas, formerly modeling the "postwar" Santa Fe and Illinois Central 

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Posted by richg1998 on Wednesday, February 29, 2012 11:27 AM

One thing for the OP to realize, much of DCC is not plug and play. Many times you will have trying times. Try this or try that, especially with custom installs. Do a reset. I do that with any new install, then make the appropriate CV adjustments. I use paper and pencil to keep track of CV values.

Do a reset and then see how the loco resounds.

Using a PC with software makes this much easier as the PC keeps the previous values. But that is another discussion.

Rich

If you ever fall over in public, pick yourself up and say “sorry it’s been a while since I inhabited a body.” And just walk away.

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Posted by richhotrain on Wednesday, February 29, 2012 10:59 AM

mobilman44

RichHOtrain,

All the locos on the layout are set for 128 speed steps.   I tried the "shorter version" and just didn't like the loss of control. 

ahhh, so speed step 20 out of 128 is similar to speed step 4 to 5 out of 28.

So, not as bad as I first thought.

Rich

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Posted by mobilman44 on Wednesday, February 29, 2012 9:46 AM

RichHOtrain,

All the locos on the layout are set for 128 speed steps.   I tried the "shorter version" and just didn't like the loss of control. 

ENJOY  !

 

Mobilman44

 

Living in southeast Texas, formerly modeling the "postwar" Santa Fe and Illinois Central 

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Posted by richhotrain on Wednesday, February 29, 2012 6:53 AM

It doesn't start to move until speed step 20?

Ouch !

Are you sure that you are set up for 28 speed steps?

Sounds like the decoder is programmed for 128 speed steps.

Rich

Alton Junction

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Posted by mobilman44 on Wednesday, February 29, 2012 6:40 AM

Randy,

  That is what I'll be doing!  

Thank you!

ENJOY  !

 

Mobilman44

 

Living in southeast Texas, formerly modeling the "postwar" Santa Fe and Illinois Central 

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Posted by MisterBeasley on Wednesday, February 29, 2012 6:39 AM

Also, be aware that CV3, acceleration, also comes into play here.  I would set CV3 to zero while adjusting CV2.  Higher values of CV3 will cause the engine to accelerate more slowly.  I have one locomotive, an IHC steamer with a Tsunami decoder, that starts like a jackrabbit even when CV2 is set to zero.  By putting a rather large value in CV3, it has a much smoother startup, although once up to speed it still moves along even a speed step 1.

It takes an iron man to play with a toy iron horse. 

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Posted by rrinker on Wednesday, February 29, 2012 6:19 AM

 Exactly correct. And this is definitely one where Ops Mode is the thing. Set the throttle to speed step 1, then start small with CV2 using Ops Mode. If the loco leaps into action, try a smaller value for CV2. If it still doesn't move, gradually increase CV2 until it can just creep along.

            --Randy

 


Modeling the Reading Railroad in the 1950's

 

Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.

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Posted by mobilman44 on Wednesday, February 29, 2012 6:17 AM

Good Morning!

Thank you gentlemen, for the confimation and the good advice.

My BLI, P2K, and Stewart locos all start up as they "should" - IMHO.   The two Spectrum 2-8-0s, both with NCE decoders I installed, just sit there until SS 20 or sometimes higher is reached.  

While I was 99 percent sure CV 2 was the answer to the problem, I wanted your input to validate that.   As you can tell by my recent posts, I've been wrestling with a few programming issues and really did not want to open up another can of worms.

BTW, all my previous issues are resolved - thanks to you all and some of the new (to me) links to manuals you all provided.

ENJOY!   

 

ENJOY  !

 

Mobilman44

 

Living in southeast Texas, formerly modeling the "postwar" Santa Fe and Illinois Central 

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Posted by tstage on Tuesday, February 28, 2012 11:01 PM

Bill,

You want to adjust CV2 (Vstart) so that your locomotive just begins moving at speed step 001.  You don't even have to fuss with CV5 (Vmax) or CV6 (Vmid) if you don't want to.

Tom

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Posted by maxman on Tuesday, February 28, 2012 10:51 PM

mobilman44

In example, if we have a loco (with a quality NCE decoder) that does not start to physically move until speedstep 20 what is the best way to cause initial movement to be at a lower number speedstep?

My "assumed answer" to this question is to adjust CV2 (start volts), and a higher number (1-255) will give more juice to the loco at an earlier speedstep.

If the above is correct and the change is made, would I necessarily need to adjust CV5 (max speed) or CV6 (Mid Speed)?

Yes, you are correct.  Raising the value of CV2 will give you more starting voltage and therefore the loco should start moving at a lower speed step.  However, I would not be messing with CV5 and 6 at that point.  I would leave the values of CV5 and 6 at zero so that they would be at the default values for the particular decoder.

Once I was done with CV2, then I would adjust CV5 to give me whatever I wanted the top speed to be, and then adjust CV6 to give me whatever mid-speed I wanted.

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Best way to adjust DCC loco movement for a lower speedstep.....
Posted by mobilman44 on Tuesday, February 28, 2012 9:51 PM

Hi,

This question has been addressed before, but I don't recall the comments and can't seem to find it in the archives................

In example, if we have a loco (with a quality NCE decoder) that does not start to physically move until speedstep 20 what is the best way to cause initial movement to be at a lower number speedstep?

My "assumed answer" to this question is to adjust CV2 (start volts), and a higher number (1-255) will give more juice to the loco at an earlier speedstep.

If the above is correct and the change is made, would I necessarily need to adjust CV5 (max speed) or CV6 (Mid Speed)?

Thank you again!

ENJOY  !

 

Mobilman44

 

Living in southeast Texas, formerly modeling the "postwar" Santa Fe and Illinois Central 

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