New n scale F7A-B units acceleration

[duke2448]

I have a problem with these locos they program easy move forward an back but accelerate seems like surging at leased it sounds that way once there up to about speed step 10 an up and as far as speed steps 1 thru 5 seem to be non existent with allthough sounds like the decoder is making noise an speed step 6 starts to creep like it should on 1 all my steamers run excellent but this the first time I encountered this type of problem any suggestions would be greatly appreciated kinda bummed this was the start of a new excursion train I'm planning won't do any good if they run like this.     Thanks for the help.

[jward]

what dcc system are you using to program these?

[duke2448]

I use the NCE power cab 1.65v , track is very clean an smooth all my spectrum steam loco work perfect maybe its the decoder in these F-A&B units, look pretty crazy compared to others Thanks.

[jward]

you can adjust cv2 to get a better start voltage on speed step 1. just increase cv2 by 10 or so until you get the result you want.
if I am not mistaken, power cab lets you read back the cv values?

[rustycoupler]

I have a similar problem, it seems like i am not getting the power i need to pull a train, i adjusted the cv,s and no change, could it be a bad motor.

[duke2448]

I don't think it would be the motor I think that it really is the decoder itself power goes threw decoder first then to motor but I could be wrong both A&B units run the same way buzzing then start moving speed step 6 to 28 sound like its surging from the way it sounds and moves. I'm going to try the cv thing tonight and see what happens.

[kewatin]

i too use the NCE power cab system,and am wondering did you program both locos a&b to the same address or is each loco different.could be one loco is not speed matched and dragging the other one down.also did you try each loco independently to see if one runs faster or slower,so as to help you understand your problem.most all of BACHMANN'S products come with the start voltage cv2=10 i always go in to my steam locos &set it cv2=0 per SPOOKSHOW'S website for better slow speed control &operation.if you want to speed match your locos you will need to get a program called JMRI.you can download it for free.if you are still having a problem ,then your best bet would be to return to bachmann for repair or replacement.for marks  SPOOKSHOW REVIEW he states these locos very ,very good in performance at all speeds, so perhaps you have a bad unit or 2.hope this info helps in resolving your problem. regards&later KEWATIN

[duke2448]

Thanks for insight did try the CV adjust to no avail stayed the same its hard to figure out but I'll have to send them back these things seem kind noisy too. Maybe I got some bad ones very bummed

[duke2448]

I believe these have can motors in them to looking at spookshows page if that true that's a real bummer what happen to the 3&5pole motors much better smooth quiet .