Bachmann Circuit Boards

[Woodboss53]

Hi '
I'm brand new to the Bachmann Message Board. My Name is Jim and I model HO. I'm going to be starting a new layout this fall after I get the dedicated room done. Also I'm going with DCC which I know very little about. My question right now is I have a Spectrum GE C40-8 and the circuit board shorted out the other night, and I am wondering if that can be purchased and replaced or can I install a third party decoder in it instead.
Thanks for allowing me in and early thanks to anyone who responds to my post.
Jim
If I did this wrong please tell me so I can do it different next time.

[richardl]

Welcome. There is an HO forum.

I think you mean the Dash 8-40C.
Is the PC board one with an 8 pin socket with a decoder plugged in or a PC board which is actually a decoder? One that is a decoder has many small multi lead chips.
Tell us what happened to make you think the PC board is defective, shorted.
The loco does not move, burnt part, smoke from the decoder?

Rich

[richardl]

Looking at the diagram page, I think this is what you have. It is a DCC on board with a decoder plugged in.

http://estore.bachmanntrains.com/index.php?main_page=product_info&cPath=66_68_191&products_id=1362

Look at the Parts and diagram page.
Lots of good info in the Bachmann site with DCC documentation also.

Rich

[Woodboss53]

Richardl It started to move and then there was smoke and  and a little explosion from one of the black capacitors. There are two of them on the board towards the front of the unit. It is burnt and smelled terrible. Its a board like similar to the picture. It has (or had) two little black 9I think they are) capacitors and one smoked and blew up.


Jim

[Woodboss53]

Richardl If you look at the complete chassis for the Dash8-40CW, that is exactly the board i have in mine. One of the two black cylinders burnt and blew up. Should I replace that or go with a decoder like MRC or Digitrax.

Jim

[jward]

first off, are you sure it was a capacitor that burned up? the board shown has two capacitors, one at each end. both are yellow. the 4 black cylinder things on the board are diodes.

second, that board is not the decoder. the decoder plugs into the 8 pin receptacle on the board. thus, changing out the decoder will not solve your problem.

it sounds like you burned up a diode. if you have some basic soldering skills, and can identify the part, you can replace it yourself. the diode should have a number like 1n4001 or 1n4004. note this number, and look for it in the parts bin at radio shack. a pack of diodes will be far cheaper than the cost of a new board. if you do decide to solder in a new diode, remember that they can be damaged by heat, so clip a heat sink on each lead as you solder it, and only heat the diode long enough for the solder to melt. one last thing, you will note the stripe on one end of the diodes. they are polarity sensitive, so make a note of which way the damaged diode is oriented, and be surre to put the replacement in the same way.

[richardl]

Richardl If you look at the complete chassis for the Dash8-40CW, that is exactly the board i have in mine. One of the two black cylinders burnt and blew up. Should I replace that or go with a decoder like MRC or Digitrax.

Jim

If this is what you have, the black cylinders are diodes. Look at the prefix for each device.
D diodes
C capacitors.
R resistors.
L inductors.

Click on the picture. It will enlarge. This PC board is usually for DCC ready locos and you plug in a decoder or it comes with a plug in decoder.

http://estore.bachmanntrains.com/index.php?main_page=product_info&cPath=66_68_191&products_id=1362

Below is what I see for this loco. A shrink wrapped decoder plugged into the eight pin socket.

http://www.bachmanntrains.com/home-usa/dwg/dwgs/H835x-IS001.PDF

Sounds like possibly a more serious issue if a diode burnt out. Not familiar with the circuit as I only have a couple small diesels and Bachmann steamers.
I thought the four diodes were for DC operation with the six pin adapter plugged into the socket but I could be wrong on that.

Rich

[richardl]

Just in case you get some more Bachmann locos. Some come with a complete PC board that is a decoder. No eight pin socket.
Some come with sound which is also a complete PC board.

I would suggest at your convenience to look though all the Parts page and Diagram pages to see all the different possibilities for Bachmann locos.

Rich

[Woodboss53]

Thank you for your information, but as you can see I'm not an electrical wizard, so I'm not sure what they call some of that stuff. But I do appreciate your help. I also did some more looking and the Dash-8 40C is also called a GE C40-8.

[ebtnut]

BTW, good luck with finding a Radio Shack that's still open after their bankruptcy.

[jbrock27]

While odds may be impacted a bit, not sure it is totally left to luck and a foregone conclusion:

http://money.cnn.com/2015/02/09/news/companies/radioshack-store-closings

Fact: there are 2 stores open near me within a few miles or so of each other.

[richardl]

Are you running this loco on DC with the six pin adapter plugged in? I was assuming DCC with a DCC controller and decoder.
If you are running DC with a power pack, you possibly have a defective motor, those diodes are usually rated at one amp. Bachman HO loco's draw under one amp.

Include details. It can help when troubleshooting.

Rich

[Woodboss53]

This is running on DC no adapter plugged in. That is why I was wondering can I buy a new circuit board for it and put a Digitrax decoder in it. I don't know why the diode burnt up. The board on the complete chassis is the one I have, that Bachmann shows. (Number H850X-00K1). I not real concerned about fixing the old one. I think its beyond repair. I'm wondering now if I can replace it with board number H850X-PCB01.

Thanks

Jim

[richardl]

This is running on DC no adapter plugged in. That is why I was wondering can I buy a new circuit board for it and put a Digitrax decoder in it. I don't know why the diode burnt up. The board on the complete chassis is the one I have, that Bachmann shows. (Number H850X-00K1). I not real concerned about fixing the old one. I think its beyond repair. I'm wondering now if I can replace it with board number H850X-PCB01.

Thanks

Jim

Yes you can replace it with that board. That is why Bachmann sells them.

Surprise the loco runs with no adapter. The adapter is nothing much. A tiny piece of PC with six wires that plugs into the socket. the last I knew. I have a couple.

Look at the below photo. You can see the DC adapter plugged in.

http://estore.bachmanntrains.com/index.php?main_page=product_info&cPath=66_68_191&products_id=1357

The loco requires this adapter or decoder to run.

You really need to spend some time looking through the Parts, at least for this loco. This is for your benefit, not mine.
Rich

[jward]

if the locomotive has the decoder plugged into the board, it will run on dc unless the analog conversion has been disabled.

have you considered hardwiring the decoder into the chassis if the pc board is bad? the decoder is probably still good even if the board it plugs into is shot.