# Decoder compatibility with Mantua trains



## Max from Brooklyn (Nov 6, 2012)

I was wondering if someone can suggest which decoder brands are compatible with Mantua F7A loco? I bought DH123D just to find out after the install that they are not compatible.
Any help would be appreciated. Thanks.


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## buck71usa (Dec 27, 2011)

What is the reason there not compatible?


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## Max from Brooklyn (Nov 6, 2012)

I don't know. When I contacted the seller, this is the answer I received. They claim that Digitrax has this incompatibility posted on their website (I did not check to be honest).


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## buck71usa (Dec 27, 2011)

I looked on digitrax website and couldn't find anything about it! Could u post a pic of the engine with the shell off? I really don't see why u can't use it!


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## Guest (Nov 26, 2012)

I am trying to think back. Did Mantua re-issue those when they opened back up for business, or do you have a 40-50 year old classic?
There were several (if not many) variations, motors, pivots, mounting (some screwed to shell, some "tabbed"), and I would bet the issue is that one leg of the motor is tied to the chassis, and then one wheel, which will blow up a decoder right now (incompatible).
If you have one old enough the armature is above the truck, and you can access the brushes and springs, isolating the grounded brush is no problem, Find a suitable piece of insulated wire, strip off enough insulation to cover the spring, and slip it over.
Solder wires to both brushes, then to motor outputs on decoder.
Then pick up power from each truck, feed to input on decoder.

One of the issues that has come into play of late, with convincing hobbyists that "plug and pray" is the only way to go, is that the skillsets are no longer being used that allows one to convert non plug and pray equipped locomotives.
How do we think folks did it before sockets were installed on locomotives?

But, some of the later Tyco engines went really cheap.....even three pole motors...and the brush is hard grounded internally.
Can it be done?
Probably, but you may have to find someone locally to do it for you.

Dave


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## Guest (Nov 26, 2012)

This site goes through the differences, up to the last ones in the 80's...called a Yugo.

http://goingincirclez.com/TycoTrains/Guide/7


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## Max from Brooklyn (Nov 6, 2012)

I am attaching pictures. I don't see anything that would ground the motor. I see two pick up wires on each side of the chassis and that is it. 

ALso, I want to point out that the train did run for about 10 minutes after I installed the decoder before it started shorting. 

The decoder is removed on the pictures, so don't be surprised by the wires. 

Thanks everyone.


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## Max from Brooklyn (Nov 6, 2012)

I posted the pics. Thanks.


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## Guest (Nov 27, 2012)

Ah, That's a Yugo. One of the later Yugoslavia built, I think. 
If it's a 3-pole motor, or the current is too high, it will trip out the decoder. You may need a noise suppressor on the motor.
When you install the decoder, you solder and shrink tube all open connections, right?
Dave


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