# DC or DCC Locomotives; How to Tell?



## grpaine (Jun 18, 2016)

I bought a bunch of HO “stuff” at an estate sale including 34 locomotives, mostly diesel. I think the majority are pretty old because they have the old style plastic couplers. One must be DCC because I found a sheet of paper saying “Thank you for purchasing this Bachman DCC-equipped locomotive”. On the back is an exploded parts image and I matched the image to the actual locomotive. 

If I understand it right, DCC equipment can run on DC but DC equipment will burn up if run on DCC. Is there a way to tell which locomotives are DCC without removing the shells from each one?


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## mesenteria (Oct 29, 2015)

Almost all decoders made after about 2004 or so are 'dual mode', meaning they can be configured to sense what kind of current they are getting, DC or square wave AC (DCC). However, that feature can be disabled in CV 29. So, ideally, you'd check using a DCC track, not a DC one, but you can tell directly if your drive buzzes and squeals fairly obviously when you apply speed steps on your throttle with DCC current to the rails. If you get the groaning and squealing, you have a strictly DC drive. If it is silent, it MAY BE a DCC drive with the feature turned off.


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## ncrc5315 (Jan 25, 2014)

If you have a DCC system, or no someone who does, place the locomotive on a programing track, and try to read back from the decoder. If there is a decoder installed, values will be read. If there is no decoder, the system will say no decoder installed.


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## grpaine (Jun 18, 2016)

I borrowed a friend's NCE Power Cab so I'll go setup a test / programming track then report back.


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## Cycleops (Dec 6, 2014)

Best way is to pop the hood, which is what you'll have to anyway if you are going to run DCC.


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## grpaine (Jun 18, 2016)

The NCE Power Cab did not seem to recognize the engine as DCC so I popped the hood. At first I thought the engine's circuit board was too simple for DCC but it matches the exploded parts diagram. On the diagram it says "6031 Digital PCB". The engine makes a whirling sound when on the DCC test track. It sounds like a computer CPU fan. 

I have another engine that runs real strong and looks newer than the others so I popped it's hood. I found a much more complex circuit board which has "Digitrax" printed on it and "5788 RTR DCC / LAMP BD". There is a chip connected with 9 wires. Sure seems like it should be DCC yet it makes the same noise as the other one when on the test track.

Maybe I'm not using the Power Cab properly. It returns a manufacturers number of 255 in both cases and when I try to change the addresses the new address is not saved.


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## morland (Sep 25, 2012)

So the 5788 locomotive appears to be a Athearn RTR brand, it is DCC ready, meaning it has the harness and circuit board that are ready for a DCC decoder to be plugged into it. At the end of the wire harness there is a dummy board plugged in where a decoder will go if you want to make it DCC. So you will need to purchase a decoder to place in it to give you DCC control. If you want to make it DCC with sound you will need to replace the board and install a speaker. Here are a couple of pictures that show the removal of the dummy plug and what a decoder looks like plugged into it. Note these are not my pictures, I found them on the internet.

This picture shows the removal of the "dummy" plug from the DCC wire harness. Do not remove it until you have a DCC decoder to plug into it's place.








This picture shows what the wire harness looks like with a DCC decoder plugged into it.








Hope that helps....

-Trever


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## DonR (Oct 18, 2012)

The pic shows a 2nd chassis under that of
the 5788. That chassis is DC. The circuit board
is for light control. It would be removed when you
install a DCC decoder which would have to be soldered
in. The 5788 can be upgraded simply by plugging in
a suitable DCC decoder as described by Morland.

Don


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## Cycleops (Dec 6, 2014)

As Moreland says the upper loco is a straight plug and play conversion, the lower one would require a fair amount of work to install a decoder. You would also have to ascertain if the motor is completely isolated from the chassis and make the necessary modifications if it is not. Maybe best saved for later when you feel more comfortable about doing these conversions.


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## grpaine (Jun 18, 2016)

I agree that the board on the chassis to the front looks pretty bare bones but the documentation says it has DCC On Board and the exploded diagram on the back of the page shows an identical board. I've uploaded the document. Are we sure this isn't some real old form of DCC?


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## grpaine (Jun 18, 2016)

morland said:


> So the 5788 locomotive appears to be a Athearn RTR brand, it is DCC ready, meaning it has the harness and circuit board that are ready for a DCC decoder to be plugged into it. At the end of the wire harness there is a dummy board plugged in where a decoder will go if you want to make it DCC. So you will need to purchase a decoder to place in it to give you DCC control. If you want to make it DCC with sound you will need to replace the board and install a speaker. Here are a couple of pictures that show the removal of the dummy plug and what a decoder looks like plugged into it. Note these are not my pictures, I found them on the internet.
> 
> Hope that helps....
> 
> -Trever


Thank you Trever and everyone else. So how do I determine which decoder is the right one? I'll skip the sound on this one. I was hoping to find a configuration tool on TCS's website but didn't find one. I know it has 9 wires so that limits the choices. It looks like the T Series is the only one with a 9 pin connector but that still leaves 5 choices (T1, T1-LED, T4X, T4-LED, T6X).

If I can get this engine to run on DCC it will buy me time to research my first DCC w/ sound engine purchase.


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## CTValleyRR (Jul 26, 2014)

grpaine said:


> Thank you Trever and everyone else. So how do I determine which decoder is the right one? I'll skip the sound on this one. I was hoping to find a configuration tool on TCS's website but didn't find one. I know it has 9 wires so that limits the choices. It looks like the T Series is the only one with a 9 pin connector but that still leaves 5 choices (T1, T1-LED, T4X, T4-LED, T6X).
> 
> If I can get this engine to run on DCC it will buy me time to research my first DCC w/ sound engine purchase.


Both manufacturers of locos and DCC decoders will recommend certain models for certain locos. If you're not doing sound, you have a lot more leeway in what to use. If you have to solder it in, really anything goes. For a plug and play loco, you have to get the connector correct (8-, 9-, or 21- pin, although there are adapters). For the one you show, a direct plug will work fine; you don't need a wired harness.


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## morland (Sep 25, 2012)

Your welcome, glad to help. Personally I generally buy Digitrax decoders when I don't need sound and just want DCC control. Digitrax has a nice decoder selector on their website. I'll put the link to it below. You can get a basic Digitrax decoder for as low as $16...TCS makes good decoders as well, I just don't know their models as well I do Digitrax's.

Digitrax Decoder Selector
http://www.digitrax.com/products/engine-matrix/decoder/

The link below is to a Digitrax decoder sold at Model Train Stuff for $15.99. It has all of the functions that you would need for DCC control of the locomotive and it is compatible with Athearn RTR locomotives. It comes with a wire harness that you will not need to use since the locomotive already has a plug-n-play socket. 
http://www.modeltrainstuff.com/Digitrax-HO-1-5-Amp-Economy-Wired-Mobile-Decoder-p/dig-dh126d.htm

-Trever


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## grpaine (Jun 18, 2016)

Since I don't have any DCC right now and this shell has a lot of room, I bought a Digitrax Premium sound decoder. That will get me started in DCC operation and I can experiment with sound. It will also buy me some more time before I purchase my first new DCC engine.


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## Lemonhawk (Sep 24, 2013)

The speaker that comes with the premium sound is now serving as the internal speaker on my computer. Its good at that, not so good as a locomotive sound speaker. I switch to an iPhone speaker ($2.50 or so on ebay) and the difference was night and day!


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