Bachmann Online Forum

Discussion Boards => HO => Topic started by: engr.todd on March 09, 2009, 11:11:36 AM

Title: Disable DC function on DCC engines:
Post by: engr.todd on March 09, 2009, 11:11:36 AM
On another forum someone mentioned something about disabling the DC function on a DCC on board Bachman engine, does anybody know anything about this? It was said to enable better or smoother starting and stopping on these engines. No other information was given.

Anybody know?
Bob
Title: Re: Disable DC function on DCC engines:
Post by: jward on March 09, 2009, 11:33:52 AM
i don't know how disabling the dc function would make a locomotive run smoother......

on some dcc systems when you power up the layout some decoders will power up the locomotive at full throttle. nothing like a runaway to liven theings up. disabling the dc function prevents this from happening.
Title: Re: Disable DC function on DCC engines:
Post by: engr.todd on March 09, 2009, 01:03:32 PM
Jeff;
I don't know anything about it. I just saw it on the MR forum. They didn't mention how to accomplish this but said it would make for better starts and stops on DCC?

Just thought I'd throw it on the table to see if anyone knows anything about this function.

Thanks,
Bob
Title: Re: Disable DC function on DCC engines:
Post by: HO-Ron on March 09, 2009, 03:28:56 PM
CV29 Bit 2 (counting from zero) This bit is forced off on some of the older DCC only sound decoders.
HO-Ron
Title: Re: Disable DC function on DCC engines:
Post by: engr.todd on March 09, 2009, 08:19:59 PM
Thanks Ron. One of the guys from our club said he knows what that's all about and can do it. I'm gonna try it on one of my 45 tonners just to see if it really makes a difference.
Bob
Title: Re: Disable DC function on DCC engines:
Post by: Jim Banner on March 09, 2009, 09:08:42 PM
Turning off analogue (dc) control in the locomotive will not give you smoother starts.  Turning off analogue control in the command station often will.  The longer time between DCC commands that occurs when zero stretching is in use can make a locomotive accelerate erratically, especially if the tracks are dirty enough to make the headlights flicker or the locomotive's decoder is not using 128 speed steps.

Try this test:  Set full speed on channel zero (channel 10 on E-Z Command.)  Then run a DCC locomotive on its DCC address.  Next, turn the analogue channel (0 or 10) to zero speed and rerun the DCC locomotive.  Do they run equally smoothly or not?  If so, don't worry, be happy.  If not, then shut off analogue operation in your command station (if possible) or ban analogue operation on your layout.

I should add that cleaning your tracks and wheels, plus adding a tiny bit of oil to the tops of the rails, will go a long way toward making starts smoother.  Just as it always has done in dc.
last comment added 10 March 2009
Title: Re: Disable DC function on DCC engines:
Post by: Yampa Bob on March 10, 2009, 04:38:09 AM
Since I have EZ Command, I can't comment on other controllers. However, all my locomotive decoders are still in dual mode. I've never had a problem with runaways or any other issue. If my locos ran any faster they would be flying off the tracks.

Besides, I have a DC powered test track in my office, very handy for troubleshooting and tuneups. 

As for the MR forum, I think it's mostly just unsubstantiated opinions. (Here in the West, we call it something else)  :D
Title: Re: Disable DC function on DCC engines:
Post by: OkieRick on March 10, 2009, 10:53:17 PM

Yampa,

When the 2-10-2 I put the TSU-1000 Sound decoder in would not run I gave Soundtraxx a call.  Sources there said CV29 has to be set to enable "dual mode" or DC and DCC.  The decoder installs DCC only (mine did).

But the 2-10-2 with the Bachmnn DCC only in it (same 2-10-2) it would run on on DC and DCC tracks.

...you gather buffalo chips too?...   :D