how can i convert a HO BNSF from DC to DCC?

[boober1942]

i purchased a BACHMAN HO BSNF DC form EBAY and i would like to convert it to DCC

[ACY]

A picture is worth a thousand words. You can use your favorite image hosting site to share a photo. Without more information I can't give you any specific help.
I will say that many older Bachmann locomotives are not worth converting as the newer models are much nicer quality overall, and have very nice detail and run much better and they often come with DCC and sometimes with sound installed as well. If you are a novice to DCC installs then depending on the locomotive it may not be best to attempt to install DCC by yourself straight away.
Generally speaking if you do try to install DCC it is key to make sure to isolate the motor from the frame and to be keen to keep track of where each wire is supposed to go to if it has a board. Most older locomotives are not DCC ready and will require a hardwired install so the ability to use a soldering iron/gun will be necessary.
Sorry I can't help you anymore specifically without more info.

[Bucksco]

The first thing to do is remove the body shell and look to see if there is a removable 8 pin plug on the circuit board. If these is a plug you can remove it and plug in an NMRA compliant DCC decoder. If you install a sound decoder you will also need to install a speaker somewhere in the loco and connect it to the decoder. If there is no removable plug on the PCB you need to trace the wiring and "hardwire" in a decoder. Check out this link if this is the case:

http://www.bachmanntrains.com/home-usa/board/index.php/topic,27726.0.html

[Copperline]

I have a Bachman 0-6-0 engine ( with Smoke) which was manufactured in 2010 I believe.. It runs on DC OK.. But I am converting to DCC.. Does anyone know the actual motor voltage? - There is a Printed circuit board - H507X#PCB02 rev A.. which has two wire wound resistors.. Anyway - I discarded the smoke unit - and Isolated the Neon Headlamp.. The Power pick ups - Engineer and Fireman side are Good.. 
Motor is Isolated from the frame - so all seems OK to put in a chip.. BUT before I do that - I just wanted a general discusssion on the motor voltage and the PCB - interaction

Thanks - Copperline Foreman ( John )

[Bucksco]

I would scrap the PCB and just wire direct from the decoder...

[jward]

Adding to what Yardmaster said. I've used a Z scale decoder. It has enough current capacity for an HO locomotive, and it is small enough to fit in the cavity where the smoke unit was.