I put an analog 2-10-2 steam (Con-Cor) on my DCC-powered track and a coded BNSF diesel loco. No problems. Both run great. Then I remove the steamer and put on an analog CB&Q diesel (Atlas). The analog diesel runs fine, but the coded diesel acts really weird. Slows down, stops, starts, goes faster, then slower, even reversed itself a couple of times. I have removed all feeders except one (I have a small layout 4'x5'). I have cleaned the track. That analog diesel still makes the coded diesel run weird. Any ideas? Thanks.
My first thought is that perhaps the non-decoder diesel is creating some shorts that makes the decodered loco behave strangely? Which DCC system are you using? Andrew
I'm using a Digitrax DCC system. I don't know why, but I haven't tried another diesel, until now. Actually, I tried two different ones, both analog (total of three now). The first, which I talked about above, is an Atlas U25B PH.2B. The second is an Atlas SD-24, and lastly an Atlas GP-7 Ph.1. The last two (SD-24 and GP-7) both had NO effect on the coded loco, an Atlas GP-38. I don't know what the PH designation means, but I listed it here anyway. Thanks.
Possibly intermittant contact or other noise generated on the track by the analog loco is interfering with the DCC signal, causing false responses. (That, or they just don't like each other). It's like trying to make it through that 5-way freeway interchange while your kids argue in the back seat. Thorough cleaning of wheels, wheel wipers, truck sideframe contacts and frame contacts would be a good start. (That, or a "time out" for the "bad" diesel) PH means Phase, which relates to prototype details modeled on the loco, not on internal stuff. Doug
The 'bad' loco may have or not have rf suppresion fitted that the others don't or do have (commonly a small capacitor across the wiring). That could be the problem in itself, or if they all have something fitted it could be that it has gone faulty on the U25B.
Just to clarify... is it one non-DCC loco that causes trouble in all DCC locos, or all non-DCC locos cause trouble in one specific DCC loco? Or something else? It does seem like the U-boat has some issues though... Whatever the combination (please tell us again... I would suggest that the first place to start is a cleaning of all wheels and all track. Andrew
I have cleaned the track and wheels and checked all track connections. Did the "quarter trick" to check for shorts (lay something conductive across the tracks). Did this at various points around the layout. All OK. Two non-DCC locos (analog), both Atlas U25B's, cause one DCC loco, Atlas GP38, to act very strange. I only have the one DCC loco at this time. Other non-DCC locos do NOT cause problems. Guy at the train store suspects GP38. I'm ordering DCC decoders for them and we'll see if that resolves the problem. Thanks for your assistance, folks.
