Rapido N scale DC/DCC silent GMD1 (first run)

CedarCreek Aug 29, 2020

  1. CedarCreek

    CedarCreek TrainBoard Member

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    Gentlemen, I've just about had it with the digitrax decoder in the GMD1 I bought in 2015. Anyone out there happen to swap out the decoder with a better one? Thinking about swapping a TCS M1 with the NMRA 8 pin socket in there. Is it a straight swap? or am I looking at major surgery? Thoughts?
     
  2. CedarCreek

    CedarCreek TrainBoard Member

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    So I took the loco apart and the decoder is attached using an 8 pin plug. Anyone know if this proprietary to Digitrax?
    It would be swell if this was something that another I could use with another decoder.
     
  3. Pieter

    Pieter TrainBoard Member

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    8 pin plugs are one of the standard plugs used by all decoder manufacturers. If you want to install a TCS decoder have a look on their webpage for a decoder of similar size with a 8 pin plug to that is currently installed in yours. If size is a problem look for nano decoders.
     
  4. CedarCreek

    CedarCreek TrainBoard Member

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    Alright did some more digging and the digitrax decoder has an 8 pin plug/socket type thing attached to it. It's not an NMRA plug
    It looks similar to the socket type connector on the TCS MC2P. TSC calls them a JST socket. Digitrax calls them a DHDP.
    Looks like they are the same... unfortunately the TCS is a 7pin and the digitrax is an 8 pin.
     
  5. CedarCreek

    CedarCreek TrainBoard Member

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    So I contacted TCS. No reply yet.
    It seems (to me anyway) that if i can get my hands on a 8 pin JST "female" connector I should be able to wire an M1 or similar decoder directly to it.
    So long as it matches the 8pin male connector that digitrax uses. Does anyone have experience with these types of connectors??
     
  6. Atani

    Atani TrainBoard Member

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    According to DigiTrax the compatible decoder should be DZ126IN and one TCS variant could be EUN651. It should use a standard pinout on the decoder port.
     
  7. CedarCreek

    CedarCreek TrainBoard Member

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    Thanks Atani, unfortunately those decoders are 6 pin and the 2014 GMD1 release has a digitrax 8pin DN136D installed.
    I don't want to use the digitrax decoder any more as I don't like the motor control.
    Digitrax sells 8 pin dummy sockets that I may have to buy to remove the socket as there doesn't appear to be an equivalent connector out there that will mate with the digitrax plug. Or I'll just have to hardwire in a new decoder. You would think the digitrax plug would be standard...
     
    Last edited: Sep 4, 2020
  8. Atani

    Atani TrainBoard Member

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    I don't see any 8 pin with that model number but I do see a DN136PS but that again is a six pin. Can you post a picture of the decode and socket?

    Most likely it is a standard NMRA plug but never know.
     
  9. CedarCreek

    CedarCreek TrainBoard Member

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    I don't have a picture but here's a link to the manual. https://www.digitrax.com/media/apps/products/mobile-decoders/dn136d/documents/DN136D.pdf
    It came installed with a "digitrax easy connect 8 pin harness" When i had the loco open id didn't look anything like an NMRA plug. It looked like what TCS calls a JST connector jst connector 8 pin
     
  10. Pieter

    Pieter TrainBoard Member

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    Digitrax made some of their decoders so that you can swap them out by either unplugging at the decoder ( jst connector) or by the 6/ 8 pin connector as well. One of the new engines coming on to the market (HO) actually now gives you the option of using either connection. Have a look at their DH166PS decoder, shows both connectors. Could also be that the 8pin plug was left off and the wires solder directly to the engine.
     
  11. Atani

    Atani TrainBoard Member

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    Ok, that is what I was thinking it would look like. That has an NMRA 8 pin connector (green board) and the JST (white piece just under the shrink wrap of the decoder).

    That appears to be how the DN136D is sold, a wire harness.

    I'd suggest just cut the wires from the JST and hard wire it rather than try and use the JST itself. A standard JST 8pin plug is roughly 26mm wide which won't fit in most N scale locos, the only way I can see it working is if it is a two row JST or a very narrow pitch JST which may be a lot more challenging to source likely.
     
  12. CedarCreek

    CedarCreek TrainBoard Member

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    [QUOTE="Atani, post: I'd suggest just cut the wires from the JST and hard wire it rather than try and use the JST itself. A standard JST 8pin plug is roughly 26mm wide which won't fit in most N scale locos, the only way I can see it working is if it is a two row JST or a very narrow pitch JST which may be a lot more challenging to source likely.[/QUOTE]

    Darn, I thought so. It looks like i'll get a TCS M1 and just swap the wires then.
    Thanks for all your help. It's too bad the plug wasn't standard between manufacturers.
     
  13. CedarCreek

    CedarCreek TrainBoard Member

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    [QUOTE="Pieter, post: Could also be that the 8pin plug was left off and the wires solder directly to the engine.[/QUOTE]

    Thanks for your reply. There is a plug, and was hoping to re-use it.
    I'm going to follow Atani's suggestion and just cut the wires at the plug and hard wire another decoder in.
     
  14. Atani

    Atani TrainBoard Member

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    The 2x4 (8 pin) connector is NMRA standard. In the case of DH166PS it is using the NMRA connector on one side and a JST on the decoder side.
     
  15. CedarCreek

    CedarCreek TrainBoard Member

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    Thanks. I was referring to the digitrax "easy connect" harness.
     

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