Chessie GP15T 2 rail

You need to ask MTH if they support the NMRA standard DCC signal, ie can their proprietary system control a DCC equiped loco.   DCC is an open system, so any mfg control system which stated  as fully compliant is able to control any other mfg locomotives or decoders.

A lot of the Atlas locos came with an pin plug that you can replace with a specific DCC decoder that plugs into the same receptacle.   The included plug just jumpers it for straight DC.

The latest MTH O gauge 2 rail locomotives come equipped with PS3 decoder boards and they will run under DCS or DCC. the reverse is not true.  DCS command stations cannot run 2 rail DCC equipped locomotives.   DCS is technically a well engineered system but it locks you into proprietary universe with only one vendor selling you decoders the system can control.  In that environment there is little market pressure for MTH to offer new product, or to hold down the price.  MTH's focus is on selling locomotives equipped with PS3, not on selling decoders for retrofit into non-MTH locomotives. 

If you go the DCC route you have the option of purchasing a command systems from any one of several manufacturers such as NCE, Digitrax, Lenz, MRC and several others.  All DCC decoders can be controlled by any brand DCC system, and there is a very large array of after decoders available at prices significantly below MTH PS3 pricing.  Another DCC advantage for diesel modelers is that AtlasO, Sunset 3rd Rail, and now MTH ready to run 2 rail diesels have DCC compatible electronics factory installed. 

If you are in to 2 rail O scale, my recommendation is to stay in the open market mainstream - go DCC.  If you have an existing investment in DCS it may be worthwhile sticking with it.  Makes for an interesting decision you'll live with for quite awhile.

Ed Rappe

PS I just ordered my first 2 rail MTH PS3 steam locomotive and am looking forward to running it on my DCC railroad.

Alan,

That "103 chip" sounds like it is an NCE 103 D14SR (see link below) and would not have enough current handling capability for a twin vertical motor O Scale drive such as the one equipped on the GP15-1 so you would most likely let the "magic smoke" out of the decoder in short order.  Besides, if this NCE 103 is indeed the chip that the seller is referring to, then it also does not have sound capability.  More details on the "chip" would be necessary to make any further judgments on it, so this is just a guess... 

http://www.highcountryhobbies....4-103-d14sr-decoder/

Your options for using this DC loco would be:

- Switch to DCC control system and purchase a DCC sound decoder that has the current-handling capability from Atlas O parts dept (may or may not be available so you have to contact Atlas for price and availability).  Next option below provides better sound quality in my opinion than these early Atlas / QSI electronics but this Atlas solution would be the closest to plug-n-play.

- Switch to DCC control system and purchase a 3rd party DCC Sound decoder designed for O Scale from Protocraft, QSI, or ESU LokSound (~$150-$200) and retrofit loco electronics.

- Switch to DCC control system and purchase a 3rd party HO sound decoder with good heat sink per a past article in O Scale Resource online magazine and retrofit and see if it works (~$80 - $100).

- Purchase an MTH DCS Protosound 2.0 electronics board (I don't believe Protosound 3.0 is available separately - may want to contact MTH to verify) and retrofit Atlas DC loco with MTH DCS electronics.

In all the above cases, you would need to install a speaker as well, which you can get from the Atlas parts dept (don't forget to ask for the speaker mounting screws as these screws and speaker will be absent from a DC-only loco).  Speaker usually installs in the fuel tank.

Scott K.

Austin, TX

Just because a loco has two motors, the NCE 103 may still handle it.   

I had small NCE decoders in Weaver U25Bs that are two motored, Weaver RS11s, MTH SW 1500, and MTH H10-44 that come to mind right off.   

 However, you must put check the loco under load and at stall with your meter on straight DC to see what the current draw is.   Many of the new 2 motor locos draw less than 1 amp under load and about 1.5 stall.    I put them on test rollers and hold with a wood block the wheels to put them under load and stall them.

Many of the older 2 motor locos such as original PAs draw too much.   I have not checked out a 2 motor Atlas loco, so the GP15 may draw more than an amp continuous running

The NCE 103 is a very low cost non-sound HO decoder who's 1.3A continuous current rating is not up to the power requirements of most twin motor China drive diesels.  I operate several "China Drive" twin vertical motor diesels (A-B-A AtlasO Erie builts and A-B Weaver passenger sharks) retrofitted with QSI "HO" DCC sound decoders.  Per suggestion of others on the old AtlasO Forum I rewired the motors in series for improved slow speed performance.  Under continuous load the units draw less than the 1.5A continuous duty rating for QSI's Titan-U decoders.  The diesels have proven their reliability over several years during open house shows hauling 30 car freights and 14 car passenger trains up 2.2% grades.  The Titan-U decoders list for $119.95 and can be purchased for less through several DCC dealers - not a bad price for one of the top rated DCC sound decoders on the market.

One recommendation I offer to those going into DCC is to invest in a digital ammeter to monitor the actual current draw on the railroad.  Due to DCC's square pulse "AC" wave form traditional analog ammeters do not provide accurate readings.  The RRampmeter sold by Tony's Train Exchange display both track current and voltage readings down to 2 decimal places.  The meter is easy to install and read and can provide useful locomotive performance information, particularly during break in running.  On large railroads running multiple trains a DCC ammeter is useful in letting the owner know if cumulative current draw is indicating it's time to add additional DCC boosters.  

Ed Rappe

Ed, and other DCC users, please know that this is my opinion of the current state of DCC still, as well as when I was deciding on a control system. I respect choices, but I went thru this already. Many DCC sound decoders are getting much better. They still require too much hastle to use without consulting the owners manual or getting extra stuff to program and utilize their features. It sounds like you're endorsing QSI Ed. They have a great product. But if it's all you'll mainly use, you are going proprietary.

 When you get into discussions about control systems, you'll find a lot of different passionate opinions. Each user decides which system to use. DCC can be described as "open". The cost of getting all the components of each DCC system, including optional programmers for installing sounds, etc. can be over the top.

 With DCS from MTH, the system has many optional features built in. It is a proprietary system. I think you'd find that most DCC users end up with whatever state of the art decoder for that moment, is what they use pretty exclusively (the new QSI for example). So I get a laugh when someone says they don't want to be tied to a closed system. I myself, preferred Atlas gold engines in HO scale for easy RTR engines with good sound. I tried to stick with them to make running large consists quicker and easier. 

 MTH offers upgrade kits that can be used to upgrade other manufacturer's equipment. After installing, the ease of programming and operation shines. As you already own the system, don't sell it short until you research what else there is.

 The price to run DCC high amp capacity with sound, smoke, and command in G scale, would scare the BG'us out of anyone. The MTH system serves me well to this day in both scales.

FWIW I have been using DCC in O scale since 1994. I started with a Digitrax system and 2A decoders as there was only that and System 1 available in the UK where I was then. Since then I have been able to expand the system without anything becoming obsolete, add wireless control, and newer generation decoders from NCE, Soundtraxx and Loksound as the sound and motor control improved. For sure DCC is a learning curve, but if you can use a PC or Mac, you can do everything you need with free JMRI software and one of several DCC to PC connector boxes that's under $100. JMRI is quite user friendly now and you don't need to know much if anything about CVs and other jargon. Today I think NCE has the best user interface so unless you need the capabilities of Digitrax Loconet, I'd pick NCE as your base system.

Recently I have been doing some testing with the RRAmmeter mentioned above. I can state that none of my Atlas dual motor drives draw more than 1.3A stalled. And at wheelslip they're well under 1A per engine. That's with the motors wired in series as mentioned above. Dan Dawdy wrote an article about this approach on his Richmond, Danville and Southern layout called "Amps is Amps" in another O scale magazine a couple of years ago. That's what got me into testing my locos current draw.

Now I am using Soundtraxx and Loksound 1A decoders with no problems in "China Drive" dual-motor engines. As long as you weight them so they always get to wheelsip before stalling you will be fine.

Now, for Pittman motored engines, you will definitely need a "large scale" (O or G) decoder. Protocraft offers an upgraded Soundtraxx Tsunami at 3.5A, NCE has the D408SR and Loksound has the Series 4 XL. I have not purchased QSI decoders separately, only used what comes in a stock Atlas loco but I expect they have a similar offering.

If your loco still has the original "dogbone" circuit board, NCE makes a plug in decoder, as mentioned above. It's the ATL-O I think, for motor control and lights, but no sound. I have one in an Atlas O GP15 and it works great. 

I also hear that Atlas will be switching to Loksound decoders soon. That's good in my opinion, as I feel Loksound's latest decoders offer the best motor control and sound quality.

My $0.02...

Pete         

Joe

I only cited QSI as a representative product for Alan's consideration as I've successfully used their decoders in AtlasO locomotives  similar in drive configuration he is thinking about. I'm sure not wedded to them as I have 25+ locomotives (9 different brands) DCC'd with decoders from 3 different manufacturers (Soundtraxx, QSI, NCE and am about to add a 4th (ESU) and a 5th (Protocraft.  If you count PS3 in the new MTH engine, I'll have 6 different brand decoders running compatibly on the same layout.   With DCC I pick the decoder that gives me the best combination of performance, sound, and price at the point in time I'm making the purchase. With DCC we O scalers get to leverage many of the developments (miniaturization, sound sets, JMRI software) and price points due to commonality with the far larger HO and N scale market segments. 

If most of your locomotives are or will be MTH and you already have a DCS system I think going with DCS makes sense.  But for someone just starting out in O scale 2 rail like Alan, without a prior stake in MTH gear, I think a non-propriety DCC system is the way to go for reason of the choices it offers today, and in the future coming out of open market forces.   

Ed Rappe

I'm not aware that anyone has made a GP15T I've only seen GP15-1s. Is this a brass engine? Thank you.

Very good advice, Ed.

Yes. I can understand your point. I have owned Soundtraxx, QSI, MRC, Digitrax, Locsound, NCE, and Big sound decoders (maybe more?) .

 Some were released as state of the art for their time. Their sounds were below par and some didn't even run well. Some didn't like to get reprogrammed or maybe I should say didn't do what they were advertised to do. One was just junk.

 I know that the JMRI software was a big step forward in DCC for easy use. I hear of guys bragging on how they can fine tune things now. They have to, to get different brands of engines to play well together.

 With the PS board, the tach watches the flywheel for precise speed control. No parameters to set. No functions have to be moved. You can move the higher number ones for convenience if you choose.

 So, if you want to play with functions and parameters, I can understand choosing DCC. If you just want to run some trains, you may choose an easier way.

 I do respect your opinions Ed. I know that you're trying to help him. I just wonder if people reading this have given DCS a chance. I feel the DCS and the NCE remote are very close in operating other than the function presets.

https://youtu.be/BtwYUQ97Kq0

  Depending on the railroad and specific details they could look similar, the main difference was inside, a T had an 8 cylinder turbo while a -1 had a 12 cylinder non turbo. I've seen brass models before but don't recall if they were T or -1 versions. Whatever locos one gets  I'd certainly go with DCC and decoders for 2 rail O scale  instead of the proprietary 3 rail control systems.. ...DaveB