Trains.com

Subscriber & Member Login

Login, or register today to interact in our online community, comment on articles, receive our newsletter, manage your account online and more!

Replacing a bachmann DCC on Board Decoder

19603 views
13 replies
1 rating 2 rating 3 rating 4 rating 5 rating
  • Member since
    April 2009
  • From: Staten Island NY
  • 1,734 posts
Replacing a bachmann DCC on Board Decoder
Posted by joe323 on Thursday, January 12, 2017 10:14 AM

I have several low end DCC on Board Bachmann locos that function OK but hum. 

I noticed that other low end decoders such as the Digitrax one I installed in my Atlas DCC ready are silent and more responsive.

Before I tear open the Bachmanns to replace the decoders I was wondering how big a job this is going to be.  From what I understand the Bachmanns are hard wired circuit boards.  I am trying to decide if upgrading the decoder to a better one is worth the time on $70 Locos or should I just retire them and buy other DCC Ready locos with NMRA plugs and buy decoders seperately.

All of these are non-sound because I operate late nights when family is sleeping.

 

Joe Staten Island West 

  • Member since
    February 2002
  • From: Reading, PA
  • 30,002 posts
Posted by rrinker on Thursday, January 12, 2017 11:09 AM

 The DCC On Board decoder has at least 8 wires. They may even use the 8 pin plug, so changine would be super easy.

 Replacing the whole board is not a difficult jobm and getting rid of the capcitors and inductors that bachmann uses can improve running even more, especially when a better wuality decoder is used. You really have ni more than 7 wires to deal with - one from each side of the power pickups, one to each side of the motor, one to the headlight, one to the backup light, and a common to both lights. It's generally easy enough to figure out because they are all wires, unlike some which use the frame as one side of the circuit. I usually remove factory boards and hardwire all my decoders, that way I know exactly what I'm dealing with, whereas the factory board introduces inknowns into the circuit path.

 Either way it should not be hard to swap out the decoder for a better one.

                     --Randy

 


Modeling the Reading Railroad in the 1950's

 

Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.

  • Member since
    October 2006
  • From: Western, MA
  • 8,571 posts
Posted by richg1998 on Thursday, January 12, 2017 11:23 AM

We are asuuming HO scale. Bachmann has different ways of installing onboard DCC.

Some diesels are a light board decoder.NCE sells the Bach-Dsl lightboard decoder for those.

https://ncedcc.zendesk.com/hc/en-us/articles/200945019-BACH-DSL

Some a PC board with an eight pin socket.

The 44 ton onboard are a 7 pin soldered in decoder.

Most of the steamers have a PC board with 8 pin socket in the tender.

Post which locos.

THe TCS decoder website shows many loco conversions with good pictures for non sound and sound.

http://www.tcsdcc.com/Customer_Content/Installation_Pictures/HO_Scale/HO_Search/search.html

There are different ways to install decoders.

Rich

If you ever fall over in public, pick yourself up and say “sorry it’s been a while since I inhabited a body.” And just walk away.

  • Member since
    April 2009
  • From: Staten Island NY
  • 1,734 posts
Posted by joe323 on Thursday, January 12, 2017 12:39 PM

Well lets see 2 GP38-2 one GP - 40's

2 GE 70 tonners and 1 0-6-0 Dockside Switcher.

Joe Staten Island West 

  • Member since
    September 2014
  • From: 10,430’ (3,179 m)
  • 2,311 posts
Posted by jjdamnit on Thursday, January 12, 2017 1:20 PM

Hello all,

It's hard to say whether the decoders are 8-pin NMRA type or Printed Circuit Board.

Removing the shell is a fairly easy process; depending on the model.

Check out the Bachmann Product Reference Page and look up the specific model you are dealing with.

Often times the schematic will tell you what type of decoder is installed without having to remove the shell.

I have had great luck with Digitrax mobile decoders. For most, non-sound, installations I used the DH126P, this is a great 2-function decoder. For a decoder with more function outputs I like the DH166P with 6-functions.

For hard-wired (soldered) installations I simply cut off the 8-pin NMRA plug.

The TCS KAM4-LED [1479] has served me well when upgrading to LED lighting. This mobile decoder can be soldered directly to LEDs without the use of resistors.

It is a 4-function decoder that is great for tight installations where the resistors might be too close a fit.

Hope this helps.

 

 

"Uhh...I didn’t know it was 'impossible' I just made it work...sorry"

  • Member since
    October 2006
  • From: Western, MA
  • 8,571 posts
Posted by richg1998 on Thursday, January 12, 2017 3:06 PM

The suggestion to pull the shell and even take a picture and post here if not sure.

You will need an image hosting site to do that. No idea if you have done that. The instructions are at the top of the Model Railroader General Discussion forum.

The Bachmann website has loco diagrams but Bachmann does change canoes in the middle of the stream and change the onboard DCC for same locos. The diagrams usually show a decoder lightboard or one with eight pin socket. I have been following the Bachmann website diagrams and forums since 2007 and have seen the differences.

Also, be aware, Bachmann does not use NMRA wire colors. Just follow NMRA wiring plans. The decoders have instructions.

My 70 ton came with onboard DCC but I ripped out the decoder and went LokSound. No idea if the Bach-Dsl with fit.

Rich

If you ever fall over in public, pick yourself up and say “sorry it’s been a while since I inhabited a body.” And just walk away.

  • Member since
    October 2006
  • From: Western, MA
  • 8,571 posts
Posted by richg1998 on Thursday, January 12, 2017 3:21 PM

joe323
                

Well lets see 2 GP38-2 one GP - 40's

2 GE 70 tonners and 1 0-6-0 Dockside Switcher.

 

The GP's should handle the NCE Bach-Dsl.

The TCS site shows the 70 ton conversion.

I gave you both links before.

Was not aware Bachmann makes a dockside switcher. If you mean the 0-6-0T, Saddle Tank, TCS also has a suggestion. I have that loco. I put in a DZ125, slightly larger than a USA dime. Runs slowly very nicely.

Remove the caps. The two green devices that look like resistors are 4.7 uhy inductors and not an issue. With no caps, they are essentially a straight piece of wire. Zero ohms. They form a filter circuit to satisfy the EU and UK.

Rich

If you ever fall over in public, pick yourself up and say “sorry it’s been a while since I inhabited a body.” And just walk away.

  • Member since
    April 2009
  • From: Staten Island NY
  • 1,734 posts
Posted by joe323 on Thursday, January 12, 2017 10:35 PM

Rich 

First of all thank you for the help.

The NCE DSL - Bach looks like a good fit for the GPs  but I cannot find the DCC on board 70 ton.

 

Andv you are right it is 0-6-0T saddle tank.

Joe Staten Island West 

  • Member since
    October 2006
  • From: Western, MA
  • 8,571 posts
Posted by richg1998 on Friday, January 13, 2017 11:07 AM

joe323

Rich 

 I cannot find the DCC on board 70 ton.

it is right in the TCS link I gave you.

http://www.tcsdcc.com/Customer_Content/Installation_Pictures/HO_Scale/Bachmann/Spectrum_GE70/Bachmman_Spectrum_GE_70.html

Go back to that link. There are many Bachmann conversions also. Try to take time to look through links.

I have the 70 ton with onboard DCC and my conversion was as involved, maybe more involved as mine included sound.

I made a styrene board to mount the decoder and used the front and rear LED's from the old decoder and included 1k resistors.

I did not use the upper weight but made my own weights suffed into the top of the shell with a speaker and baffle.

Rich

If you ever fall over in public, pick yourself up and say “sorry it’s been a while since I inhabited a body.” And just walk away.

  • Member since
    April 2009
  • From: Staten Island NY
  • 1,734 posts
Posted by joe323 on Friday, January 13, 2017 11:27 AM

richg1998
 
joe323

Rich 

 I cannot find the DCC on board 70 ton.

 

 

it is right in the TCS link I gave you.

http://www.tcsdcc.com/Customer_Content/Installation_Pictures/HO_Scale/Bachmann/Spectrum_GE70/Bachmman_Spectrum_GE_70.html

Go back to that link. There are many Bachmann conversions also. Try to take time to look through links.

I have the 70 ton with onboard DCC and my conversion was as involved, maybe more involved as mine included sound.

I made a styrene board to mount the decoder and used the front and rear LED's from the old decoder and included 1k resistors.

I did not use the upper weight but made my own weights suffed into the top of the shell with a speaker and baffle.

Rich

 

 

Thanks again Rich.  If I can get to the trains this weekend (My wife is undecorating the house from the holidays a multi day trip though Christmas Wonder Box land)I will take off the shells and look around.  After thinking about it a bit I think I will leave the steamer alone as it only runs excursions during the Holidays and convert the diesels.

Joe Staten Island West 

  • Member since
    October 2006
  • From: Western, MA
  • 8,571 posts
Posted by richg1998 on Friday, January 13, 2017 12:02 PM

The 0-6-0T was quite easy but I have been soldering for many years. No idea about your soldering experience. I like the gearing in that switcher.

The DZ125 fit right in very easily.

A couple train companies are now using plastic clips to secure the wires to the decoder board. You stick the bare wire through the copper platted hole and slide the clip in place. I have read of some not thinking that method is very efficient. Time will tell.

I am sure you know, there are many diiferent ways to do DCC conversions. Many are not plug and play if you read through the TCS website.

Good luck.

Rich

If you ever fall over in public, pick yourself up and say “sorry it’s been a while since I inhabited a body.” And just walk away.

  • Member since
    January 2018
  • 3 posts
Posted by 1090 on Thursday, January 11, 2018 11:21 AM

Okay, let's refine this question.  I am too, very interested in this question.  I have just purchased a Bachmann F7 with decoder "On Board".  It is N scale.  Although I checked with both Digitrax and Bachmann ahead of the purchase about compatibility (Digitrax.."Maybe" and Bachmann, "We don't know") there is no communication between the DCC and the engine, no lights, no hum, no run.  Digitrax does offer a couple of decoders for this N scale F7, but I am wondering about how reasonable it is, that is, for a first timer, to replace, what I've been told is a Lenz decoder, in this Bachmann F7.

Thanks for any help

  • Member since
    February 2002
  • From: Reading, PA
  • 30,002 posts
Posted by rrinker on Thursday, January 11, 2018 5:46 PM

What address are you using? Have you tried programming a different address in it?

                              --Randy

 


Modeling the Reading Railroad in the 1950's

 

Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.

  • Member since
    January 2018
  • 3 posts
Posted by 1090 on Thursday, January 11, 2018 6:34 PM

Hi Randy.  I've used this Digitrax 100+ with DT200 throttle (an old Big Boy) only on HO and although I hardwired those locomotives, they just worked.  I'm just not sure how to even start to change the address.  What I know is that currently it is default 3 for the 128 step for Digitrax decoders but the Lenz decoder is a 28 step.  Do you have a reference that you could send me to on how to approach this change in address?

Subscriber & Member Login

Login, or register today to interact in our online community, comment on articles, receive our newsletter, manage your account online and more!

Users Online

Search the Community

ADVERTISEMENT
ADVERTISEMENT
ADVERTISEMENT
Model Railroader Newsletter See all
Sign up for our FREE e-newsletter and get model railroad news in your inbox!