[janedoedad]

I purchased a DCC ready Bachmann Spectrum2-8-0 at the train show last week. Tested the engine on DC and it worked fine. Installed a Soundtraxx Tsunami TSU-2200 decoder and speaker. That's when the fun began.

When running the engine it will randomly stall (no sound) and restart in a jerky manner. This happens at all speeds, less often when going full throttle. When not moving all sound effects work fine.

The problem that baffles me the most is when trying to use the Horn or other sound effects - the engine will stop dead and MAY come back to life after releasing the F? key.

Checked the wipers and pickups, cleaned the wheels and track, verified that all power connections are intact. Results unchanged.

DCC system is a MRC Prodigy Advance2.

I'm thinking that maybe there are not enough amps/volts going to the track to support this engine. Output on the wall adapter to the DCC system is 12V/1.6A. (Didn't get a MRC adapter with the Prodigy) This has been adequate for other locomotives. however, most are lower end models and likely don't draw a lot of power.

Advice, ideas and suggestions are welcomed and appreciated.

Thanks!


JDD

 

[D&J Railroad]

I would be inclined to think it may be your power supply.
12v 1.6A is at the barest minimum, if not, below what is needed.

 

[janedoedad]

Yes Sir.

That's pretty much what I came up with after writing my post.

Thanks!!

 

[J.Albert1949]

If you completely mute the sounds, will the engine then run smoothly...?

 

[DonR]

What AC voltage do you get when you probe
the track? A DCC track should have around 14 volts.

Don

 

[CTValleyRR]

You are right. Your unit is starved for power. It's trying to put 3.5 amps out to the rails, but it's getting less than half of that from the wall, and the command station uses some amperage as well. The additional demand of producing sound probably doesn't leave enough to turn the motor. It requires a 15-16V, 3.5 amp power supply.

If you got it new, contact MRC and request that they send you the power supply. One is supposed to come with it. If not, get a power supply with an appropriate output.

 

[janedoedad]

Thanks for the replies and input.

Will check all that out and reply in the AM. Can't get to the layout right now as SWMBO wanted to park in the garage tonight. (Something about cold weather and frost. . )

Thanks again!!



JDD

 

[janedoedad]

Going to answer each reply in order, then tell you what was figured out.

@D&J Railroad - My error. Using the MRC power adapter which is 15v/1.6a.

@J Albert - No changes in the behavior of the engine.

@Don R - 14.6 using the MRC provided adapter rated 15v/1.6a

@CT Valley RR - Ordered a 15v/4a power supply.


Now, on to my failure to notice the obvious.

After probing and poking for an hour or so, I finally figured out the problem - which should should have taken much less time if paying proper attention.

The power pick up for this engine is a wiper on each drive wheel (8) plus two wheels on each side of the tender. Noticed that the driver wipers were not maintaining contact with the wheels. When pushed or pulled half of the wipers had no tension against the drivers. I'm guessing that at some point in time, a previous owner had removed the bottom plate to the underframe for some reason or another and the wiper pick ups were damaged during reassembly. Removed the bottom plate and found that some of the wiper leads were bent and no longer had any outward tension, which meant no electrical contact. Thus resulting in the problems in the OP.

Update: Found the underframe available on the Bachmann website for $11.00. This should fix the problem.

Thanks again for your input and advice. Next time I will look closer before posting.

Have a great weekend!


JDD

 

[DonR]

14.6 volts is normal for a DCC track.

Usually, loco stuttering, pausing and the like
is suffering poor electrical continuity from wheels
to decoder. That you have found.

Don