Top speed for Athearn Genesis with Sound hitting 80MPH w CV5 at 25

[Srwill2]

Most of my locomotive fleet is non sound with Digitrax decoders.  Recently purchased a couple of Athearn Genesis with sound.  To make consisting easier, I have an Accutrack speedometer.

Here is where I am pulling my hair out.  I have set all of the non sound w digitrax to run at top speed of 65 mph and CV5 is set in the 150 range, with CV6, to get about 30 MPH being in the 50 range. Non sound locos are working great.

The sound locos have CV5 set about 25 and one is still hitting 80+ MPH!  Is there  another CV that I need to change- maybe a speed table or something? 

Anyway, my goal is to consist a sound loco with a non sound, but right now, I can't even get 1 to slow down enough to be remotely realistic. Any tips on slowing down this loco?

[rrinker]

 You pretty much have to use user-defined 28 step speed tables because the special OEM edition of the Tsunami used by Athearn doesn't support CV5. And they wonder why I don't like Tsunami decoders..

 Here is the AThearn user guide:

http://www.athearn.com/Content/PDF/UsersGuideDiesel_1.11.pdf

Notice under the CV listing, CV2 for start speed is there but no CV5 (or 6). So it's off to the 28 step speed tables to adjust it so it runs with the other locos that just need simple 3 step settings to run nicely.

                               --Randy

 

[Srwill2]

So much for easy...  

[peahrens]

I'm with Randy with my dislike for the Tsunami, particularly the lack of CV5, CV6 as well as the diesel horn performance.  I changed out the one in my Genesis GP9.

rrinker

Notice under the CV listing, CV2 for start speed is there but no CV5 (or 6). So it's off to the 28 step speed tables to adjust it so it runs with the other locos that just need simple 3 step settings to run nicely. --Randy

I did, however, accomplish my first consist with the then Tsunami'd GP9.  I got around the entry of each speed table value by using the straight line speed table (set CV25 =2 to activate) and then adjusting forward & reverse "trim", CV66 & CV95, respectively by lowering the values to less than 128 default.  That alows adjusting the max speed (all speeds are reduced) to match the mate.  As I recall, the Kato RS2 I was matching was slower at top speed, so I could use the Tsunami loco's trims to slow it to match the Kato at top speed. (If the Kato were faster, I could have left the Tsunami loco alone and just adjusted the Kato CV5 & CV6 to match the Tsunami). 

Since the Tsunami had no midpoint CV6, I then adjusted the Kato CV6 to match the locos at mid speed step 63.  As both have CV2 you can adjust both of those for similar speed step 1 start speeds (at smooth movement). 

Now I'll mention that to do the above you first need to activate speed tables.  That involves resetting CV29.  See Table A on page 16.  My Genesis Tsunami CV29 default was 6, meaning speed table off, analog (DC) operation on, speed steps 28/128 and normal loco direction.  Just substitute the value for CV29 for what you want.  As an example, just activating the speed table from the value of 6 would require changing CV29 to 22. (I chose a different value to turn analog off and to reverse the normal loco direction.)

The above is not simple but easier in my view than having to adjust all the speed table values individually.  It does require being satisfied with a straight line speed curve. 

[Srwill2]

Paul, Thank you!  I really appreciate your suggestion and will be trying it tonight.  As much as I like simple, I am learning DCC programing is anything but.....

[Srwill2]

Thanks for the help.  I was able to get CV 29 redone and played w the speed curve options.  Tried the exp 2 and found that at step 14 it was running about 28 mph.  Since I am going to consist a couple of GP's on a small layout, I should not be able to match the non sounds and be good at the low end.  Thanks again for the great advice!

[fieryturbo]

There's a lot of conflicting reports on this, but both my Bachmann Sound Value and Athearn SD40-2 with an Econami-100 have the VMax CV (CV 5).  JMRI was able to both read and write this value, and I did this last week so it isn't just a fuzzy memory.  Unless the Athearn OEM decoder is a special case, I think that CV5 just may not be documented by the instructions.  It's worth trying to read and write that CV in any case.

You also didn't say what model the Athearn Genesis loco is, so there's no way to know what generation of decoder it is either.  That's important when we're discussing OEM stuff because there isn't always a specific decoder model to go by.