# DCC TO DC Help needed



## 7&45 (Jul 11, 2012)

I recently purchased a Rivarossi 4-8-4 FEF from a forum member with the complete understanding that it had a bad decoder install and did not run. What I am wondering from the board is if it can be converted back to DC? 

If so what do I need to do?


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## Brakeman Jake (Mar 8, 2009)

If it has a "wired" decoder,simply cut it off and connect red wire to orange and grey to black.That will energize the motor.If you want to have the light working...then there's a little more to it.Since the original board is gone,you'll need some more help to have them work.You'll need to say if a LED has been installed or if it still has a bulb and diodes and/or resistors will be needed to have them working right.

What about simply replacing the decoder?It is also possible that the actual decoder has its programming messed up.


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## 7&45 (Jul 11, 2012)

Would this be in the tender or the engine itself? Any tips on taking the shell off the locomotive at all?


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## Brakeman Jake (Mar 8, 2009)

Generally,there's not enough room in the loco for a decoder.That would definitely be in the tender.


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## Brakeman Jake (Mar 8, 2009)

Forgot to ask...HO or other scale?


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## 7&45 (Jul 11, 2012)

It's HO.


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## Brakeman Jake (Mar 8, 2009)

Depending on who did the install,the decoder could be in the loco.Are there wires between loco and tender?


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## 7&45 (Jul 11, 2012)

There are wires between, with a connector. I haven't had time to try and get into the tender yet. I will try to find time to take a couple of pictures if that would help.


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## Brakeman Jake (Mar 8, 2009)

Pics would indeed help,even more so with the tender shell removed.May be the decoder may be identified and we'd have a better idea of the install.

Question...do you have a DCC system?IF so,you might be interested in trying to find and correct the problem.


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## NIMT (Jan 6, 2011)

Another option would be to see if it has a 8 or 9 pin decoder, then you could pull the decoder out and install a jumper plug to make it run DC.


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## 7&45 (Jul 11, 2012)

Alright. I tore into the tender today and all that I can see inside is what looks like a speaker. There appears to be a capacitor in the cab area. Any ideas or suggestions on getting the shell off?


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## Brakeman Jake (Mar 8, 2009)

I haven't done one of these,however the shell is likely bolted on.It probably has one small screw in the smoke stack in front and one or two screws under the cab in the rear.The front screw may be under the front frame too however.

What you just said worries me a bit...seems like a sound decoder was installed then removed.I don't see why there would be a speaker in the tender and the decoder in the loco...all should be in the tender.It would be a good help if you could post picture(s) with shell removed.


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## 7&45 (Jul 11, 2012)

I was home with a sick kid today, so my time was limited. I contacted the seller and learned it has a digitrax sound decoder. Once I peel into the shell I will take some photos. Just might take a day or two.


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## NIMT (Jan 6, 2011)

It's possible that it has 2 decoders in it, one for sound and one for motor control.


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## 7&45 (Jul 11, 2012)

Alright. I finally have time to work on this again. I have opened up the locomotive and it was a digitrax sdh164 chip. I decided to go with brakemanjakes suggestion and I went black wire to gray wire and orange to red. Still a no go. 
I dug out my multi-meter and put it on powered rails. There is power to the rivets that the wires are soldered to, but not to the ends of the wires that are soldered to them... So I am going to test my soldering skills and see if it was simply a bad solder job on the power feeders. Wish me luck.


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## 7&45 (Jul 11, 2012)

SUCCESS! Not exactly sure what was wrong in the first place. And I almost feel guilty considering what I paid for it. 

Thank you everyone for your help with this! 

I will close with a quote from my 4 year old- "look at that baby chuff!"

Paul


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## Brakeman Jake (Mar 8, 2009)

Do you mean the decoder was OK and is now activated or did you go with your first goal turning it back to DC?


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## 7&45 (Jul 11, 2012)

Back to dc.


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## rrgrassi (May 3, 2012)

I bought a Rivarossi PM Berkshire off of ebay. It had a Digitrax Z scale decoder in the loco shell. This was my first foray in to upgrading to sound, so I bought a Digitrax sound and motion decoder. Changed it all to tender mounting and used the Soundtraxx 9 pin tender to loco plug set to get motor power, track power pick up and light poer to the loco. Modified the tender to hold the chip and the speaker, and also has additional power pick up. Worked really well! So then I upgraded to the Tsunami Heavy Steam. Y ear later, still working very well.


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