Hi gang! First time posting here. I have an issue with an older steamer I am trying desperately to bring forward into this day and age. It is an old Riverossi 4-8-2 Chippewa orange and gray steam loco. I recently wired up a NMRA socket to the existing wires. The motor is isolated, but the headlight is not. The wiring is all correct and neatly soldered with right rail pickup coming from engine and left rail pickup coming from tender. I then tested it on DC with a jumper I made that I know is correct and everything lights up and runs great. I then plugged in a Lenz silver series BEMF run decoder and a MRC sound decoder in tender (with stock resistors on wires), and the engine runs sporatically to barely at all. So I disconnected the white plug on MRC decoder and it still ran crappy. I then thought the run decoder was defective, so I bench tested a new decoder of the same type and it ran fine on DC with decoder in. Then I thought fixed, so I hooked up sound and same thing sporatic. When I disconnect the sound decoder, both run decoders remained sporatic. Did the sound decoder reprogram the run decoder? Did the sound decoder (new) fry the run decoders in some fashion (I know the wiring is correct)? The DCC tests were performed with a super chief set with stock address of 03 for sound and run. What could the problem be???
I got a little lost here about exactly what was done. When the Lenz decoder is the only one hooked up, programmed, then what happens on DCC? What does running crappy mean? It could be as simple as dirty wheels. Can you try to run it with jumpers directly into the loco (skipping the wheels)? What do you mean when you say with “stock resistor”? Where is the resistor for the headlamp? Do the lamps work properly? The two decoders (one running only a speaker) shouldn’t effect each other at all.
I got a little lost here about exactly what was done. When the Lenz decoder is the only one hooked up, programmed, then what happens on DCC?
Before the MRC was hooked up, it ran fine with the try of the second LENZ. I believe the first LENZ did too, but can’t remember.
What does running crappy mean?
Sporatic - move an inch stop, move half inch stop, move 10 inches stop - LIKE dirty wheels, but the lamp and sound decoder defy that theory plus test track is brand new and cleaned.
Can you try to run it with jumpers directly into the loco (skipping the wheels)?
I did this and same results as track - ran fine definitely with second LENZ then MRC was added again, put on test track and sporatic. Problem is disconnecting MRC still sporatic at this point (LENZ by itself). This what puzzles me as a pretty good troubleshooter unless the LENZ was damaged or CV’s inadvertently set by something.
What do you mean when you say with “stock resistor”?
The resistors that came on the red and black lines of MRC sound only decoder (and was new)
Where is the resistor for the headlamp?
No
Do the lamps work properly?
Yes I believe so
The two decoders (one running only a speaker) shouldn’t effect each other at all.
I agree, so what now? 2 broke new LENZ decoders by what? Or MRC screwing it all up. I am considering setting MRC to different address than LENZ and consisting them to prevent interference between them. Weird problem indeed!
Take out the MRC. Reset the Lenz to factory defaults. If it runs fine after that, it is that some of the CVs you set for the MRC are also used by the Lenz and are not valid settings. When you have two decoders in oen loco, you should use plugs and sockets ont he track power leads to make it easy to disconnect one or the other when programming. Many sound CVs are beyond the range of those used by motor decoders, but not ALL.
Too strange, I have no ideas. But if it were me, I would go back to the first sentence and re-remember. Put both LENZ on the test bench and reset to defaults. Install the LENZ only in the loco. Get the loco running perfectly. Then and only then try to install the sound. I like the idea of a different address too. That allows one to program each decoder separately from the other.