One decoder two engines.

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Ken Bird

New Member
OK guys here is one for you. I want to power two locos, an A&B F7 units with one decoder. The units will be coupled together with a drawbar. Rather than use two 2 decoders I want to use only one for both units. The motors would be in series. Anyone have any comments on this arrangement?
 

ianacole

Well-Known Member
I think you'd need to verify that the motors pull at exactly the same speed. One of the advantages of DCC consists is that you can speed match motors so they pull exactly the same, but that requires 2 decoders.
 

Rico

BN Modeller
As Ian says it could be done if both locos match each other, I have atlas locos that are exactly the same.
I suppose another thing to check is if the combined amperage draw doesn’t exceed the decoder rating. If you wired the pick up from both you’d have pretty good performance I’d think?
I know someone thats thinking of hooking up a sound decoder to the actual track with speakers at both ends of a mill building. The plan is to run any combo of DC locos on that track with the sound being constant. I should check in with him...

I should add that the idea came from trying to shoehorn a decoder into a trackmobile.
 

Ken Bird

New Member
As Ian says it could be done if both locos match each other, I have atlas locos that are exactly the same.
I suppose another thing to check is if the combined amperage draw doesn’t exceed the decoder rating. If you wired the pick up from both you’d have pretty good performance I’d think?
I know someone thats thinking of hooking up a sound decoder to the actual track with speakers at both ends of a mill building. The plan is to run any combo of DC locos on that track with the sound being constant. I should check in with him...
Thanks for the reply. I'm looking at doing Athearn F7s and I think a 2 Amp decoder would work ok. They will have new motors and modern drive shafts.
 

GeeTee

Well-Known Member
I would get a higher amp rated decoder , most 12V motors will have stall current specs in excess of 1 amp. I haven't checked the Athearn blue box "new" motor but it wouldn't surprise me if it stall current > 1 amp. The "gray" motor would be even higher .

I usually take the Athearn "new" motors out , toss them and replace with Hollands in F7s , But then I have a box full of Hollands that I paid around $2 a piece for ,They were surplus 30 years ago and were selling by the eyeballed pound( $30 for a bag full) .
 

Ken Bird

New Member
I would get a higher amp rated decoder , most 12V motors will have stall current specs in excess of 1 amp. I haven't checked the Athearn blue box "new" motor but it wouldn't surprise me if it stall current > 1 amp. The "gray" motor would be even higher .

I usually take the Athearn "new" motors out , toss them and replace with Hollands in F7s , But then I have a box full of Hollands that I paid around $2 a piece for ,They were surplus 30 years ago and were selling by the eyeballed pound( $30 for a bag full) .
I've had good luck with Sound Trax rated at 2 amp.s Most have a 15% over amperage. NCE are also great but they are not in the sound business as yet. The worst experience I have has are Digitrax. Many failures but they are good on warranty replacements.
 

trailrider

Well-Known Member
I've had good luck with Sound Trax rated at 2 amp.s Most have a 15% over amperage. NCE are also great but they are not in the sound business as yet. The worst experience I have has are Digitrax. Many failures but they are good on warranty replacements.
I would definitely check the stall current of the units, and then call Soundtraxx to see what they recommend for this particular application. They are very helpful, and it would save you a lot of time and trouble.
 




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