Stewart C628 decoder placement

Model Railroader Electronics and DCC
1

I’m still scratching my head over this one. On my Stewart Alco C628 the NMRA plug is underneath the PC board. I’ve never see this before. How does one fit a decoder there? Doesn’t look like much place.What decoder should I use?

Thanks,

Tom

2

Tom

Train control systems has a decoder designed especialy for the Stewart locos. I believe its a DP2x. Its a great decoder with Back EMF and excelent lighting software.

Pete

3

Tom

Here is a link to see a picture of the decoder for your Stewart.

http://www.tcsdcc.com/decoderpics/sb.html

Pete

4

That is the way I did it too. Plugged in a Digitrax decoder with the NMRA plug, ran the wires between the PCB and the tower, and stuck the decoder to the underside. The only thing I didn’t like was how hot the rectifiers for the classification lights get. Other than that, it worked just fine.

5

Thanks for the link. However mine is different. There is plenty of room on the circuit board shown photo in the link you provided, but as you can see my NMRA plug is located further back over the flywheel next to a connector. See the photo attached. Now I wonder, is the black 8 pin connector removeable? If yes then maybe I can reposition it on top. I don’t want to try to take it off as it may be soldered on. I hope the photo can be viewed.

6

Tom

It looks like you could fit an MC2 decoder with short harrness under the board. The decoder would be between the motor and board. If you turn the board over there may not be enough room for the shell to fit back on.

Pete

7

Another option is to just get a decoder with wire leads and solder them to the circuit board where the 8-pin connector is. Just remember you’re looking at the bottom and keep the order of the pins correct. You can desolder the 8-pin plug and actualy feed the wires through the holes or just solder them right to the surface.

–Randy