# Decoder Installation



## JoeG (Feb 3, 2013)

To all, 

I bought a soundtraxx MC2H104OP decoder for my Athern SD70MAC DCC ready engine. Im not sure how to install this decoder into the current board. When I bought the soundtraxx decoder I thought it would come with a plug that would fit right into the tan plug located on the engine. Since the decoder has an 8 pin connector I am not sure if I need another adapter or what. Any help would be greatly appreciated. 

Thank You, 
JoeG

P.S. I know this is probably a beginner question!!


----------



## Mark R. (Jan 26, 2013)

I honestly don't know why Athearn stopped installing the eight pin plug on their boards .... the holes are there for one, why not install it ?

The simplest option would be to cut off the 9-pin plug from the engine, and the eight pin plug from the decoder, then then just splice the wires together matching them color for color.

Solder the connections and use some shrink tubing over each connection.

You could also solder an 8-pin plug into the provided holes if you happen to have one laying around.

Mark.


----------



## JoeG (Feb 3, 2013)

Mark R. said:


> I honestly don't know why Athearn stopped installing the eight pin plug on their boards .... the holes are there for one, why not install it ?
> 
> The simplest option would be to cut off the 9-pin plug from the engine, and the eight pin plug from the decoder, then then just splice the wires together matching them color for color.
> 
> ...


I looked online and found that I was missing a piece for the 8pin connector.


----------



## Mark R. (Jan 26, 2013)

I don't think you are missing it per se, I have a bunch of Athearn boards that came without the 8-pin plug soldered into the holes. 

Maybe it was done on purpose or maybe there was a huge batch that missed getting them. (?)

Mark.


----------



## JoeG (Feb 3, 2013)

Mark R. said:


> I don't think you are missing it per se, I have a bunch of Athearn boards that came without the 8-pin plug soldered into the holes.
> 
> Maybe it was done on purpose or maybe there was a huge batch that missed getting them. (?)
> 
> Mark.


Im not sure, It was a used engine off of eBay so I'm not sure if it was suppose to be on there or not.


----------



## Bwells (Mar 30, 2014)

At the right side of the board I see 8 holes, could this be where the decoder plugs in?


----------



## JoeG (Feb 3, 2013)

Bwells said:


> At the right side of the board I see 8 holes, could this be where the decoder plugs in?


That is where the pin connector goes. This is what it looks like the in pin connector in the board.


----------



## Bwells (Mar 30, 2014)

Okay, you lost me. That looks like a completely different board than the one on your loco.


----------



## JoeG (Feb 3, 2013)

Bwells said:


> Okay, you lost me. That looks like a completely different board than the one on your loco.


It should be the same, they are both Genesis DCC Boards from Digitrax.


----------



## Bwells (Mar 30, 2014)

Sorry Joe, but I don't think I can be much help as I have never done a DCC ready loco. From what I understand there are a few jumpers that need to be removed when operating in DC mode (track to motor/track to lights) and then just plug in the decoder. I'll follow as you sort this out, thanks.


----------



## Cycleops (Dec 6, 2014)

Hello Joe, you could do one of several things. You could solder the eight pin connector onto your board but that may be a bit tricky if you're not an ace at soldering. You could cut the nine pin connector off and solder your decoder wires to them adding heat shrink tubes for insulation. You could also use the contacts which are under the black square insulators to solder the decoder wires, they may be marked with where they go. You might be able to find a nine pin to eight pin adapter. You can even dispose of the board entirely if you wish. Ironically Soundtraxx do a decoder on a board which simply snaps in and replaces the existing one.

The easiest and best option imho would be the second.. Good luck.

If you go with any of the other options don't forget to remove the jumper plug.


----------



## redman88 (Nov 25, 2015)

Remove the heat shrink from the circled area. And pull the connector out








Pull the DC plug from the connector









Now reconnect the DCC decoder to the harness from the board.


----------



## JoeG (Feb 3, 2013)

redman88 said:


> Remove the heat shrink from the circled area. And pull the connector out
> 
> 
> 
> ...


Thank you so much!! That worked. You just saved me $12.00


----------



## redman88 (Nov 25, 2015)

JoeG said:


> Thank you so much!! That worked. You just saved me $12.00



KISS ( keep it stupid simple)


----------



## Cycleops (Dec 6, 2014)

Glad you got it sorted. The Tsunami is a great sound decoder.


----------



## redman88 (Nov 25, 2015)

Okay I have to ask. How many didn't even think of the connector on the DCC decoder board?


----------



## Cycleops (Dec 6, 2014)

Hadn't occurred to me because the connector is hidden under the shrink wrap, but when you posted I checked on mine and there it was.


----------

