Need guidance to troubleshoot decoder installs

drgwspup Dec 29, 2020

  1. drgwspup

    drgwspup TrainBoard Member

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    Hi everyone. Looking for some assistance in how to diagnose by installation failures. As I don't have a permanent layout, the locos come out around the holidays and then are not seen for months. That situation will be addressed with the planned basement finish ;) but I am building a fleet for when that day comes.

    I have several Atlas GP30 classic locomotives that I have installed TCS decoders into over the last several years. I use the NCE PowerCab system. All worked fine after the initial install. This year I had a number of them simply not work when I give them their annual opportunity to run on the xmas layout

    Here are the two basic issues:

    1) On some locomotives I can read the CV and set the long and short address through programming on the main feature. The subject locomotive was the only locomotive on the layout at the time. Some will light up when put on the track other do not. Despite setting the addresses, nothing happens when I try to increase the speed.

    2) Two others had an ominous high pitch buzzing/chatter when place on the track and then were quickly removed when they would not respond to the Program on the Main.

    SO before I launch into a maintenance program, I was looking for ideas on what to look for instead of just tearing them all down and possibly repeating my errors. Any and all suggestions would be greatly appreciated!

    Mark
     
  2. MK

    MK TrainBoard Member

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    It sounds like you run them about once a year as you mentioned their annual opportunity around the Xmas layout.

    The first thing I would do, even before tinkering electrically, is clean their wheels. Could be just dirty contacts. Do that first and report back.

    Note: I'm assuming the tracks are clean too?
     
  3. drgwspup

    drgwspup TrainBoard Member

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    Thanks for your reply!

    Yeah, track is cleaned with a bright boy before the layout is assembled annually. I also use a liquid track cleaner/conductivity fluid on the Unitrack rails. Rails are in good shape as I been running a dozen other units without issue, including a Kato FEF, Atlas Geeps 30/35s with drop-in TCS decoders and older RSD 4/5 with TCS CN decoders in them. I would think that if it was a dirty wheel situation it would plagues all my units that go through the annual use them/store them cycle or I would see jerky hesitation in the units. But I'll give it a look..

    It seems to me that if I can read the decoder info and the lights works (on some), then the issue would need to be in the current flow from the board to the motor. Sound reasonable?

    The second scenario has me more concerned as that seems like a short or maybe a bad decoder. How does one determine if the decoder is bad versus a bad install job? I don't have a decoder tester.
     
  4. MK

    MK TrainBoard Member

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    Tracks and wheels cleaned. Check ✔

    Yes, if you can read and write CVs and the lights work, then it's 98% a decoder to motor connection issue.

    Usually a decoder doesn't go bad by itself. However I have heard of a decoder "losing its memory" after sitting around for awhile and not being used. It's never happened to me personally but I've heard of people reporting that.

    People resolved that by factory resetting the decoder and reprogramming the address. Where it gets annoying is if you have a bunch of others CVs programmed and now have to redo.
     
  5. Mike C

    Mike C TrainBoard Member

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    Do the Atlas engins have motor tabs that are supposed to make contact with pads on the decoder ? If so you may want to solder a wire between the two instead of relying on just the contact ......Mike
     
  6. drgwspup

    drgwspup TrainBoard Member

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    any ideas on the other scenario What's causing the buzzing/chatter?
    Yeah they do. And what I am finding is that the tabs are not lining up with the pads on several of these. I got a few repaired tonight.

    Any thoughts on what is causing the buzzing/chattering in the other units that don't run?

    Thanks for the reply
     
  7. drgwspup

    drgwspup TrainBoard Member

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    Ok this is embarrassing. Situation 2 above is resolved. Went i put the locos away in their boxes the last time I used them, I must have place two non-dcc units in boxes marked as dcc. When I pulled the shell off, the issue was obvious. The stock lighting board was still installed. (doh!)The high pitch chatter was a DC motor being fed by the DCC.

    AARGH! Sorry to waste everyone's time.
     
    Sumner likes this.
  8. MK

    MK TrainBoard Member

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    No worries!!!! You ain't the first one or the last one to do that (DC loco on DCC tracks)! :ROFLMAO:

    What is it they say??? It's a learning experience! :D:LOL::)
     
  9. BigJake

    BigJake TrainBoard Member

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    One of the REALLY nice things about JMRI Decoder Pro software is that it can remember all of the settings in all of the registers for your entire roster. Just make sure you read the entire decoder into the roster entry.

    Ever have a problem with a decoder acting wonky, just throw it on the programming track and re-program it to exactly what you had before, in one (long) step.
     
  10. drgwspup

    drgwspup TrainBoard Member

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    The thing is that I would have bet a lot of money that I had installed TCS decoders in all my GP 30's, 35's and 40's. It never occurred to me that I had missed a couple. Dang it, more decoders to buy.

    Appreciate your kind words MK.

    Big Jake: JMRI is still a bit ahead of me. I'm struggling with decoder installs, lol. But thank you for the suggestion.
     
  11. Sumner

    Sumner TrainBoard Member

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    You don't need to use all of the features of JMRI but using just one, DecoderPro will be a tremendous help with those decoder installs and keeping track of your roster. Look into it sooner vs. later, you won't be sorry,

    Sumner
     
    BigJake likes this.

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