Hi folks. I have never used a DCC system before, but as more than half my locos came with decoders, and most of the rest are simple drop-in replacements, I am going to get one. I have a question before I do, though. I have an older Atlas GP9 which I lovingly modified to represent a chop-nosed Western Maryland unit. This model is NOT DCC friendly, and I would have a nightmare of a time finding a place for a decoder in it. I have heard that you can have one non-DCC locomotive on a DCC layout, and it can be told when to respond rather like a DCC unit... is that true? Or do i need to look for another frame/chassis for this model? All the best, Amanda
Digitrax will allow the operation of one non-DCC loco. It won't run nearly as well as one with a decoder, it will "sing" (make a humming noise) the entire time it's setting on a powered track and could end up being damaged by the DCC signal. I've tried it with a few locos out of curiosity and it's nothing that I would recommend and definitely not something that I would ever be satisfied with. So, yes, would get another chassis for your favorite loco.
There are a few options for you. First, there are many installers who can install a decoder in the GP-9 for a reasonable fee. While you can run a DC locomotive on DCC, Digitrax uses address 0 for this, it is generally not the best thing to do. A DC locomotive running on DCC does not work as well as one might think. It runs more like a DC throttle than a DCC throttle. There are several advertisers on this site that provide those services, you may just want to contact one of them. This is especially true if you only have 1 locomotive to convert..... The older chassis have more weight with them that means better pulling power.
My first thought is how can I mill the frame to make a pocket for a micro decoder. Won't be drop in, but it can be done. I have a mill, so I have done a few of my own and for others.
I've put ESU LokPilot Nano and Zimo decoders into older Atlas GP9s with no issues, for others. These are very small decoders and the frame only requires minor milling.
Thanks all. I will see about milling the frame. I have looking for a good reason to buy a small mill - maybe this is it. I certainly don't want anything to damage any of my locos, and I do want good performance.
I don't know how old your Geep is, but I've put a ESU LokPilot V.4 micro in my non-DCC ready geeps on the rear frame "shelf" without modification except for a minor "channel" to wire the motor (see below). It will fit underneath the light board, which you can modify for power pickup (I replace the stock light with a sunny white LED). You will have to hard-wire and insulate the motor. To do this, I cut off the phosophor-bronze strips that contact the frame, except for maybe 1/16" of an inch. I use that 1/16" to solder the decoder wires to, and then cover the brush cap and the solder joint with electrical tape. The only frame mod needed is to use a Dremel with a 1/8" round ball cutter to cut a small channel in one side of the frame to route the wires to the motor. A milling machine would make a neater cut, but it isn't necessary for this - a Dremel and a mostly-steady hand will do it just fine. Unfortunately, I don't have a photo of any of these, because I've now replaced them all with sound decoders. But it really isn't that hard - anyone with modest soldering/Dremel skills should be able to do it easily. But after you're done wiring, use a multimeter with a continuity testing feature (or some other continuity tester) to make sure you don't have any shorts between the frame halves. And then put the engine on a programming track (NOT on your full-power main track) FIRST, and make sure you can program it successfully. If you can, then the install is good to go. John C.
I'll use WM183's thread to ask a DCC question because the thread's title fits my status too. I'm an old skool N Scaler with no experience with DCC. A friend sent me some of his N Scale trains. I put this Atlas Classic (Chinese copy of former Kato design) SD-35 on my DC oval and it wouldn't move. I removed the shell this morning and found this circuit board atop the chassis. Is this a DCC locomotive? If so, I applied low DC current for only a few seconds a few times. Could I have fried the decoder doing this? Sorry for the dumb question!
My answer is no, DCC decoders have an option to either use DCC and DC modes or just DCC only and not DC. From your picture it might be a DCC decoder but not familiar with that board.
Yes, that is absolutely a DCC board. Looks like one of the old original Lenz or NCE boards that Atlas used way back. These are very basic and are notoriously finicky. Did the lights come on at all or everything dead? These can be set to run in DC mode, but first it needs to be verified that the board is making good contact with the frame, and clean contact with the motor leads (underneath it). If you are DC operations only, the other option is to get a DC board from Atlas for it. DC input will not harm a DCC board. First thing I would do is take the board out, and check to ensure the motor is good (using a 9V battery). Then, with multimeter, check that there is continuity from (unpowered) track to the frame on each side. Then reassemble and see if the thing works (of course, if DC mode has been disabled, and you don't have DCC, it still will not respond).
Good to know I haven't ruined the DCC board. I'll follow your suggestion to remove it and test the motor. If it works, I'll then buy a DC board if I can figure out which one to buy. Atlas' website shows only one style of board remaining in stock for the SD-35, Item 470009 N DCC READY 30/35 PCB-WHITE LED @ $12.65 and that reads like what I already have. Looking at eBay, the correct Atlas Item might be 447009, but it shows as a U-25B part only on Atlas' website @ $11.50. I think I'll phone Atlas to be sure. Thanks!
I dismantled the DCC SD-35 and the motor and mechanism are fine. So, I need to get a new DC Analog Board. I found a parts list in the Atlas box and it shows that I need an Atlas P/N 494009. (I'll also need two other parts, as I lost a screw and broke a clip on the motor saddle! I never had these problems with my Minitrix U-28s. ) I noticed that the motor in my DC unit has a black plastic end and the former DCC unit has a grey plastic end as seen below. I have a hazy memory that one color indicates a newer-generation slow speed motor. Is this right and which is which?
From the picture the GRAY motor is the older. WHY? the chassis is not designed for a PCB like the top one. IMHO the bottom chassis will need to be modified to install a decoder. The top one would have the better motor.
I forgot to mention that I removed the DCC PCB from the bottom unit with the gray motor. Sorry about that! I read somewhere last night that the Black is the old fast motor and that the Gray is the newer slow motor, but I want to double check. How 'bout them Vols?
Dennis - Both of those chassis are the same. The one in the foreground with the grey motor takes the same board as the one in the background. The "pop-up" motor contact strips require a board, and you can see the contact point slots for the board at the four corners of the superstructure.