DCC pcb for EMD GP40$)

[ducky]

I have a Bachmann EMD GP40 Diesel Locomotive whih does not have DCC or SOUND.  I wish to install DCC or DCC & SOUND but do not know what PC Board I need, if you can help me with a part number and where to purchase from it would be appreciated

[richg]

 Just  looked at the diagram. Have you done anything like this before. It does not look easy..

Rich

[richg]

A basic sound decoder. MRC & Digitrax, and speaker starts about $50.00. SoundTraxx, about $100.00. LokSound, about $140.00. Some shops will not stock MRC because of a lot of issues with them in the past.
I doubt Bachmann will ever sell sound decoders separately. They do not at this time.

If I see the diagram correctly, the motor contacts connect to the top and bottom half of the frame and have to be isolated. Squeezing in the speaker will another issue.
Looks like the loco has light bulbs.

I have done a Walther's H12-44 with a SoundTraxx but had to grind away part of the top frame half and isolate the motor contacts from the frame halves with Kapton tape.
I used resistors for the LED lights.
Most decoders do not have resistors for LED's and are made to connect to 12 to 14 volt light bulbs.
A few decoders are starting to include resistors for LED's and connections for 1.5 volt light bulbs. You have to check the decoder specs and all decoder manufactures have documents for their decoders on line.

Rich

[Tom M.]

I have installed SoundTraxx decoders in Bachmann GP40s for a couple of my DCC installation services clients.  I used the AT-1000 style decoder and used double-sided foam tape to mount it to the frame.  The biggest issue is machining the frame to make room for the speaker and enclosure.  I used a medium oval speaker and enclosure sold by Tony's Train Exchange (also available from other vendors).  I machined the rear portion of the weight, but you have to be careful not to compromise the overall structure because of the way the frame is mounted to the rear truck.

I modified the frame in my milling machine, but most folks do not have one of these.  The milling process took me about 2 hours.  If I did it again, I would do it using a bandsaw with a metal cutting blade installed.  Doing it that way should only take a few minutes.  I guess you could also do it with a "hacksaw" if you could secure it in a vice to hold it steady without damaging the frame.

Good luck,

Tom

[ducky]

Thanks for your reply Richg, the answer to you first question is NO, I have just started using with DCC

[richg]

Thanks for your reply Richg, the answer to you first question is NO, I have just started using with DCC

Ok, a lot of DCC, including sound is not plug and play. There are many variations depending on the manufacturer and loco model.
Soldering experience will be needed with many installations and having a multimeter will be a big advantage. The resistance scale is needed at times as well as being able to read voltage and current.
Understanding the difference between LED's and light bulbs will be important also.
More than once I have read of some who smoked decoders, sometimes two or three because they did not have enough knowledge of what is involved.
I belong to about twenty MRR forums.
I am not trying to portray a dim picture. Going from DC to DCC is a big step in many ways.

Look through the links below for some info. There is a lot so take your time.
Look in Mr DCC Curriculum section.

http://www.mrdccu.com/

http://www.tonystrains.com/tonystips/dccprimer/index.htm

http://www.members.optusnet.com.au/nswmn2/DCC.htm

Yeah, I know. Information overload. Store the Links in Favorites for future reading.

Rich