Model Railroading > Momentum in Atlas sound engines

I have two GP40-2s and a Dash 8-39B that have momentum turned on. I'm using DCC does anybody know how to turn the momentum off trying to speed match with three others that don't have momentum.

CV3 is acceleration and CV4 is deceleration, setting those to zero would turn your momentum off, but I strongly recommend against doing it. Sound decoders lose much of their realism with momentum set too low because the sound processor bases what it will play on the difference between the throttle speed step and the actual speed step. That sound controlling difference will go away with no momentum. What you should do is program momentum into your non-sound decoders to match what atlas has in the sound engines. CV 3 & 4 are NMRA standard so all decoders should support them.

Barry Draper

Those cvs are already set to zero trying to speed match three sound Units together two of the the three have way to much momentum the one with no momentum is the faster starting engine.

Reset CV8 to value 8. That should reset everything....including the address. We your speed matching, hat is the best place to begin. Then set the address and you an begin. If you still have momentum, check your gears, you may have a stripped gear.

J

Joel Brazy
Coatesville, PA

Are they QSI? If so, you need to turn off their "regulated throttle".

Set CV49 to 4
Set CV56 to 0

Net result CV56.4=zero

Yes they are QSI I will give that a try

Setting CV49 and 56 did the trick thanks for the help

You're welcome. You're not the first one to run up against that issue.