Decoder Install Question

[shwrailroader]

Hello All,

I am a detailer and locomotive rebuilder. I recently picked up a Bachmann SD40-2 in the Wheeling and Lake Erie paint scheme. I would like to upgrade the analog board and install (hardwire) a Digitrax DH123D decoder in. Is the chassis already isolated, or do I need to isolate it before I do the install, and how do I do that.

[richg]

Hello All,

I am a detailer and locomotive re-builder. I recently picked up a Bachmann SD40-2 in the Wheeling and Lake Erie paint scheme. I would like to upgrade the analog board and install (hardwire) a Digitrax DH123D decoder in. Is the chassis already isolated, or do I need to isolate it before I do the install, and how do I do that.
[/quote

Pretty simple. Pull the shell, do a visual, use your ohm meter to see if there is continuity between the motor contacts and frame. Many times a visual will tell you.
I have to assume there is no eight pin socket for a decoder on the present PC board.

You might consider a NCE Bach-DSL decoder. They are specifically designed for Bachmann diesels and come with a LED on each end.

Rich

[shwrailroader]

Ah great! I did open it up as the locomotive number had to be changed from 7377 to 6384. I already had the DH123D in my possession, but I will keep in mind the NCE decoder. Thanks!

[richg]

I just looked at the DH123D decoder and it appears you have to hardwire if the loco does not have an eight pin socket. If it does, get a eight pin to nine pin adapter.
I have done a couple Digitrax DZ125 decoders using the hardwire method. I have small shrink tube, NMRA colors also and I use Kapton tape to secure the decoder in place. Very thin and tough.  Much better than electrical tape.
In the future, you might consider getting a Photo Bucket account. That way you upload a photo of a loco, then link that Photo Bucket photo to the Bachmann forum. That is the only way to post a photo here. A photo, many times is worth a thousand words. You would be amazed at how much info you can get from a photo. Many here do that.

Rich