Installation of a DH166 decoder in a P2K SW-1200.

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Well-Known Member
Has anyone else installed a decoder in this locomotive? I'm finding it to be a very tight fit! My intentions at the start was to also install a Keep Alive device in the locomotive. After working on the installation for a while I realized that unless I wanted to give up the cab interior, a keep Alive was simply not going to fit! I'm almost done with the installation and may take some photos, once I have the thing running.


Well-Known Member
Staff member
I installed an NCE D13SRJ 9 pin Quickplug into a Genesis MP15AC and even though they are longer than a SW1200, it was still tight. I have an Atlas similar MP15DC that has factory QSI Quantum sound in it but have never been game to open it up to see how the did it. Both have full cab detail.


Section Hand
Nice to read the information since I have several locomotives that are awaiting NCE non-sound decoder installations. Space is at premium in the shells.

Thanks for sharing.



Well-Known Member
I've completed the installation and the loco is working well. Lights work and everything. I put a Digitrax Decoder in a Athearn Blue Box SW1200 and don't recall having as much trouble with the installation! There must have been a bit more room in the Athearn Loco. is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to