Bachmann EM1 Decoder Meltdown

Dampfloko Jan 24, 2023

  1. Dampfloko

    Dampfloko TrainBoard Member

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    i have a first run EM-1 that I ran in DC mode and the decoder fried the other day. Of course Bachmann has none available. Is there a hardwire work around solution to get this running again? Is there a universal decoder available that could be used? In the first run the decoder wires are soldered to the pcb
     
  2. Moose2013

    Moose2013 TrainBoard Member

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    @Dampfloko

    Do you intend to run it on DC, DCC, or both?
     
  3. Inkaneer

    Inkaneer TrainBoard Member

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    My EM1 melted the front tender truck when it derailed on a Peco C80 switch. The module builder used the C80 switch despite being told to only use C55 switches (there is a difference between the two). Of course, Bachmann did not have any tender trucks in stock. What ever happened to support after the sale? Anymore, the hobby industry is taking on more of the appearance of a very expensive scam.
     
  4. John Moore

    John Moore TrainBoard Supporter

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    When one of the decoders quit in a Bmann 44 tonner I ended up sniping the wires to the decoder and simply running the truck pickups to the motor wires. Of course I lost the headlights but it gets run as the 2nd engine in a lashup. Bachmann is hit and miss on parts now, mostly miss.
     
  5. CSX Robert

    CSX Robert TrainBoard Member

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    Any small hardwired decoder should work. Here's the exploded diagram for the tender including the wiring diagram for the decoder.
     
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  6. badlandnp

    badlandnp TrainBoard Member

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    I would take the time to replace the decoder with a new Loksound 5. It isn't too difficult, the hardest part is sorting out which wire is which since Bman uses all black wires.
     
  7. Moose2013

    Moose2013 TrainBoard Member

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    @badlandnp

    The original poster never stated whether he needs the EM-1 to run DC, DCC or both.

    Since he stated that he was running it on DC, then perhaps he doesn't need DCC capability. If that is the case, he could unsolder and remove the factory decoder and hard-wire the board for DC-only running.

    If he does need DCC capability, then he could replace the factory decoder with any decoder he liked, be it an inexpensive Digitrax DZ126 or similar non-sound decoder or a more expensive ESU Loksound or similar sound decoder.

    [​IMG]
     
    Last edited: Jan 25, 2023
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  8. Dampfloko

    Dampfloko TrainBoard Member

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    Thanks for all replies. I am DC only. Is it possible to splice the blue wire to the front headlite wire to make that operational?
     
  9. badlandnp

    badlandnp TrainBoard Member

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    Yes, sorry I missed the DC thing. Just hookup the light board to the power and it should work ok. I believe the Bman light board self regulates.
     
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  10. Moose2013

    Moose2013 TrainBoard Member

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    The issue will be how to modify the board once the decoder is unsoldered and removed from it.

    Moose seems to recall old boards similar to this one having tiny "jumpers" to complete the circuits when there was no decoder.

    Cannot yet find an image or instruction sheet that shows it.

    Will dig through Moose's old papers to try to find one...
     
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  11. badlandnp

    badlandnp TrainBoard Member

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    That shook loose a cobweb or two. Yes there is a jumper method, now you mention it. Let's hope the moose finds the documents....
     
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  12. Moose2013

    Moose2013 TrainBoard Member

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    Moose HAD the paperwork from all the old Bachmann & Spectrum locomotives JUST THE OTHER DAY. Cannot recall where da bloody @#$% they went...

    Anyway, attached is the Bachmann diagram sheet of the EM-1 tender and associated decoder board.

    The diagram sheet shows the PCB board's numbered decoder wire connections.

    You will need to solder in "jumper" wires to these numbered connections, as appropriate to complete the electrical paths from the electrical pick-ups to the motor and headlight.

    If you need more information, then you'll need to wait until Moose has morning coffee ... Or wait until someone else chimes in...

    Bachmann EM-1 Tender & Decoder Board Diagram.png
     

    Attached Files:

    Last edited: Jan 25, 2023
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  13. Dampfloko

    Dampfloko TrainBoard Member

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    I cut the wires at the decoder which leaves enough wire to strip the ends and twist together. Connecting 8 to 1 and 4 to 5 gets the loco rolling again. No. 7(blue) is supposed to be power to the lites. Would 7 get spliced to 6 and/or 2 to get lites back?
     
  14. Moose2013

    Moose2013 TrainBoard Member

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    @Dampfloko

    Someone please correct this if Moose has it backwards:
    • Connect #4 to #7, and #8 to #6.
    • Think of #6 and #7 as the locomotive light and #4 and #8 as track power.
    • Light common (+) is #7. Front light (-) is #6.
    • Positive (+) track power is #4. Negative (-) track power is #8.
    • Since the locomotive light is presumably an LED, it should only light if you have the wires connected properly.
    • See sketch below for color vs. number vs. function, ignore "NMRA 8 pin connector"

    [​IMG]
     
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  15. freddy_fo

    freddy_fo TrainBoard Member

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    Assuming it has a rear LED too do you want the lights to be directional i.e. rear light turns on when in reverse and front light on only when in forward?
     
  16. Dampfloko

    Dampfloko TrainBoard Member

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    Isn’t red usually considered the positive and black the negative? Or is it opposite in train world?
     
  17. freddy_fo

    freddy_fo TrainBoard Member

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    Is the throttle in reverse or forward?
     
  18. Moose2013

    Moose2013 TrainBoard Member

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    Upon further investigation, more coffee and review of a couple of older Spectrum tenders with factory jumpers in place:

    Factory jumpers appear to make the following connections:
    • Connect #8, #1 & #2
    • Connect #4, #5 & #6
    • The common light, #7, does not appear to be connected to anything; presumably, the PCB board provides directional power for the locomotive & tender lights.
    upload_2023-1-26_9-54-36.png upload_2023-1-26_10-1-38.png upload_2023-1-26_10-10-28.png
     
    Last edited: Jan 26, 2023
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  19. Dampfloko

    Dampfloko TrainBoard Member

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    Moose deserves a nice bowl of delicious Moose Munch for all his hard work. Much appreciated.
     

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