N Scale F7A and B decoder cv values

[toyzforme]

Hey
Mister Bach Man, I have your F7A and B units in N Scale and one moves faster than the other when set to the same speed.  I wan't to change them so that they both run the same at the same speed settings.  Right now they don't and it makes running them difficult.

Thanks for the help.

[kewatin]

 with the basic bachmann dcc decoder you are very limited to what you can do regarding cv's the only way to effectively speed match decoders is with a program called jmri  .in order to use that program you will have to install a new decoder that  supports more cv inputs.failing to not want to do that i would first try setting your start voltage by changing it from 10 to 0  on both units &see if that helps and or try each one individually and ramp up the start voltage and see if that will help. this is about the only option you are going to get with this basic bachmann decoder.
rgeards&later kewatin

[toyzforme]

thank Kewatin

What CV number is the starting voltage etc as well as the others.   I realize that it is basic but if i can get them the same it would be easier to do a consist function

[kewatin]

 cv2 controls the start voltage. which ever unit runs the faster of the 2 i would try that unit first and set it at 0 and try it and work up from there.go now higher than 10  .i don't know if you will get the results you are looking for,but it is worth a try. other than that the only other option is to remove the motor from the b unit &run it as a dummy,or again remove both decoders &replace with 2 new decoders.but you will still have to match each unit with JMRI .you can download that program for free .just google it. their is a learning curve to it. maybe if their is a model railroad club you could visit some one there would probably program them for you.
regards&later KEWATIN

[spookshow]

What CV number is the starting voltage etc as well as the others.   I realize that it is basic but if i can get them the same it would be easier to do a consist function

These are very basic decoders and CV2 is pretty much your only option as far as trying to speed-match two locomotives. A list of all supported CVs can be found in this document - http://www.bachmanntrains.com/home-usa/images/44913_Decoder_IS.pdf

Also, you might want to try addressing whatever mechanical issue is causing them to run at different speeds (for example, one might have excessive lubrication goo gumming up the gears). They're not hugely complicated, so the list of possible problem areas is pretty short.



Good luck!
-Mark

[toyzforme]

Thanks everyone for the info and the pdf.  Both units are brand new and would have thought they would run the same LOL.  I will give it a go and see what happens.  I looked and didn't really see a drop in decoder for these.  Digitrax wants me to solder in a decoder and I haven't had the best of luck on trying to convert some old DC locos to DCC.  So now I just buy them with it already installed.