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Discussion Starter #1
Hello, I recently purchased a MRC Prodigy Advance2, and some decoders to install in a couple locos. I put a NCE P2KSD, in my Proto 2000 GP30. I then set it on my designated program track, and proceeded to program it, I think. I followed the instructions to the "T", and it seemed to be going well. I did not however set the SV, or any of the other voltages, mainly due the fact, I have no idea as to what those settings should be. Also, I thought I read in the instructions for the decoder, that it comes preset with all the settings it needs for the locomotive to run. I did change the address of the loco, as per the instructions of the Prodigy, it states that most decoders are 3 by default. So, I'm thinking its programed, as the Cab, said "sending" or "send".
After that, I set it on the main line and proceed to start it rolling...only to have it sit there, looking all pretty and new and doing NOTHING! No lights, no go...nope.
I double checked my wiring, and it all checked out. ( I actually took the bus wires off the Prodigy and attached them to my MRC Tech II transformer, and put on a old non dcc locomotive, and it worked fine. So I switched the wires back to the Prodigy and double checked the decoder wiring, and that seemed okay.) Even though the NCE decoder instructions are shown with reference to the front, could that be wrong? Also, there is a red wire that is attached to the frame/weight, does that need to be moved for a better connection?
With that, I am about to lose interest in this hobby if I don't get this figured out soon here.
Its obvious that I'm not electrician, but they make it sound so easy to switch over to dcc, until you read the instruction.
Thanks for any help.
 

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Programming addresses requires powered rails, pickup by the locomotive, transmission through the locomotive to a working decoder, programming CV's, and finally, removing power from the rails. This last step is often not done, forgotten, not understood.

Address changes, at least for the Digitrax system I know, is done in 'Paged Mode', or broadcast mode...no other active decoders can be on the rails at the same time or they'll change everything at the same time as well. All other CV programming should be done 'on the main', or in what Digitrax calls "Ops Mode".

I have never installed a decoder. However, I do know that a decoder is only meant to have two wire inputs...nothing else, no red wire to part of the chassis, frame, or to another component...UNLESS...it is an output from the decoder. The decoder should never get power from any source other than from the two input wires, and they come from the appropriate polarity/phase wire per the instructions. For example, on the left side, power from the left rail, that goes to input (follow the instructions). Right side pickup goes to the only other input left.

From there, you have several outputs from the decoder, to the motor, to lights, to the speaker...if it's a sound decoder. That should be it, but remember I have no experience installing decoders.
 

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I just now, well about 20 min. ago, put a Digitrax DH126D decoder in my Athearn RTR GP60M, DCC Quick Plug Equipped. I also watched a video on YT as to the installation of the decoder, it was pretty cut and dry. As soon as the dude put the decoder in, he put the loco on the track and it took right off. So I did the same, and it worked, but it was slower than slow. I'm going to read up on this dcc stuff some more. It seems to me that some of the information provided by MRC, and even Digitrax, is kinda vague...at least to me. Thanks for your information.
 

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I have an MRC Prodigy Wireless, and it sounds like you did everything right as far a programming the loco. You don't need to set SV, Acc, and Dec to start with; you can use them later to tweak the performance of your loco (SV -- Starting Voltage -- especially, governs how much voltage goes to the motor in speed step one, and you can tweak it so that the loco just crawls along). Similarly, your slow loco is probably being governed by the speed settings in the decoder -- boost the max speed CV to make it go faster.

Anyway, your intuition on what is wrong with the loco with the NCE decoder is right: the decoder requires that all current input and output goes through the decoder. The motor must be electrically isolated from the frame. Maybe clipping that wire will do it. Or you may need to look deeper for another connection (many older DC locos use the weight and frame as the return path to the rails).

Good luck!
 

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Discussion Starter #5
I'll get a picture of the proto tomorrow and hopefully put it here. Maybe someone can give me a for sure as if that wire that is soldered to the weight is the problem, thanks.
 

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OP:

I'd set CV 8 to "8".
This RESETS the decoder, completely.

Remember that the engine number is also reset to "3" when you do this.
Then, start over.
Does the engine now run better?

If so, I would be very careful about making changes, and any changes that I did make, I would do incrementally. That is, make a change, run with it for a while before making -another- change.

Also remember that no other engines should be on the track when you do this.

I have 3 Proto2000 GP30's.
One has a Digitraxx DH165LO.
The other two have Soundtraxx MC1h102P8 decoders.
 

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Discussion Starter #7
I will give it a try, thanks. I was re-reading to manual to the Prodigy, and it has a section to read the loco's decoder values. Well I tried that, and nothing happened as it should have. After entering " read pgm track", Adr appears and will flash. It instructs me to read the number and press enter. Upon doing so, "read" flashes rapidly along with the "Link" light on the power pack. I will try what you suggested in the mean time, because something is better than nothing.
 

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Also, CV29 must be correctly configured with a value that reflects what you want the loco to do. Google "CV29 calc) and you'll get examples pop up immediately. Know how YOUR decoder needs CV29 to be configured per its manual, or if you know it is NMRA DCC spec compliant, the calculator should do it all for you. Set a value, program it (press enter), and the loco should now have the correct speed table, directional lighting, etc. You'll still have to adjust both CV2 (which is V-Start, setting the lowest voltage at speed step 'one', that gets the wheels turning, even if creeping barely). From there, set volumes, set CVs 3-6 as you would like your locomotive to behave based on your function and throttle inputs. For example, if you have a drag engine hauling 20 hoppers, you'd want inertia (CV3) to be about 3/4 up into the range specified for your decoder ...in the manual. You can whiz your throttle right up to notch 8, or full forward reverser on a steamer, and watch your decoder marvellously accelerate your long heavy consist just like a real train. For momentum, CV4 should have about the same value.

Some get unnerved by such long decelerations in CV4, but many/most decoders have a brake function (F4..?), which will decelerate your train inside of two or three feet instead of 12 or more, depending on what the initial speed was at the time you dumped the air.

One final important point. If you use the cab number imprinted on the model, many of them are considered to be 'long addresses' by decoders. For example, for non-LokSound decoders (if I recall correctly), any address above 127 is a long address, or 'extended' address, and CV29 must take that into account. Use the calculator.
 

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The Prodigy can't read your CV values because the decoder is shorting through the weight and frame. Isolate the motor from the frame. That's step number one in any decoder installation in am older loco. Don't do anything else with the loco until you have done that.

The rapidly flashing messages is your system trying to read the value, encountering a short, and then resetting.
 

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Hey JAbert1949, sorry to thread stalk, but I sent you a private message and I was hoping you could shed some Conrail insight for me! Thanks, Lou
 

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Discussion Starter #11
CTValleyRR, So, if I snip that wire that goes to the weight, where will I attach it then?
 

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Discussion Starter #13
Being that I had it connected to the board the way the instructions illustrated, could that smoke the decoder?
 

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Discussion Starter #14
JAlbert1949, I was going to do what you said and set CV 8, to 8, but I do not yet know how to do that, and the instruction to the Prodigy, do not explain it very well.
 

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CTValleyRR, So, if I snip that wire that goes to the weight, where will I attach it then?
As Michael said, nowhere... provided that you have two wires connecting to power pickups on opposite sides of the axles. You should have two, and only two wires connecting the decoder to the power pickups.

The instructions would not have actually told you to connect a wire to the weight or chassis, because that's not how DCC works. However, you're not going to damage the decoder. Worst case is that you have no circuit, and therefore no power flow.

Do you have another DCC locomotive that you can look at for reference, to see how that one is wired?
 

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JAlbert1949, I was going to do what you said and set CV 8, to 8, but I do not yet know how to do that, and the instruction to the Prodigy, do not explain it very well.
I haven't cracked the directions to the Prodigy in forever, but you want to program a Configuration Variable (8) to a value of 8. I think the instructions for doing that are on the back of the handset. If not, look at the section on "Programming a decoder" at the bottom of page 2-5. Steps 8 and 9 (top of page 2-6) are the key ones for you (just hit enter to bypass the other steps for now, because what your about to do will wipe them out anyway). When it says CV#, hit 8 [enter]. Then hit 8 [enter] again. That's it. Decoder reset to factory default (including an address of 3).
 

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Discussion Starter #17
Thanks, I think I'm over thinking this because I'm getting anxious about getting this thing going. will keep you posted as to what happened.
Thanks again.
 
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