How Install Bachmann 8 pin Decoder in Spectrum DCC Ready K4

[d_hitt]

I have a DCC ready Bachmann K4 84013 and am trying to figure out where to install the 8 pin Bachmann 44915 decoder in this loco.  I took off the tender top and see some circuit boards but no obvious place to plug in the decoder.  Do I have to open up the loco?

[richg]

The DCC ready usually has a tendeer with a single PC board with an eight pin socket. A DC adapter might be plugged into it. My DCC ready, 4-4-0 and 4-6-0 were like that.

I just looked at the Bachmann K4 diagram and I see a tender with sound on board. There are two PC boards.
Do you see a speaker under thee PC boards?
Are you sure you do not have the DCC sound on board version? Have you tried the loco yet?

My HO Spectrum ten wheeler sound on board had two PC boards. A sound decoder and a PC board with an eight pin connector that the sound decoder plugged into with an eight pin plug.

Bachmann is always changing their DCC installs in the tenders.

Rich

[d_hitt]

This doesn't have sound.  I looked and I don't see a socket where this would plug in.  What would said socket look like?  Thanks

[richg]

One thing many fail to do here is take a photo and upload it to the forum. Makes things a lot easier to sovle. Get a Photo Bucket account and copy and paste the link here.

Below is my HO Spectrum 4-6-0 with on board sound. The is the PC board with the eight pin socket. It is not a decoder. A six pin adapter can be plugged in for DC only operation.



Below is the sound decoder and it plugs into the PC board. Notice Bachmann does not uses the NMRA colors for the decoder installs.



Rich

[richg]

Below is a DCC ready USRA Medium tender Bachmann use to sell a few years ago. You can see the eight pin socket.



Rich

[richg]

Below is a diagram of the K4 DCC ready that Bachmann use to sell. A single PC board with 8 pin socket.

http://www.hoseeker.net/assemblyexplosionbachmann/bachmannk4spectrum462.jpg

Below is the DCC with onboard sound that Bachmann sells right now. That is right from the Bachmann site. It shows the PC board with decoder.

http://www.bachmanntrains.com/home-usa/dwg/dwgs/H844X-IS00.PDF

That is why a picture would help a lot in troubleshooting your issue. A picture is worth a thousand words and usually a lot less frustration.

Rich

[richg]

Below is  the DCC ready K4 tender from the Parts page.

http://estore.bachmanntrains.com/index.php?main_page=product_info&cPath=66_68_170&products_id=1152

And another. You can see the single PC board with the DC adapter plugged in. The adapter is NOT a PC board. It is a six pin plug which is what you might be seeing. That has fooled many users as I belong to a bunch of MRR forums.

The loco should have come with a diagram that shows the PC board and six pin plug.

My 4-4-0 DCC ready, 4-6-0 DCC ready and 4-6-0 with on board sound all came with diagrams and what I call wordless instructions.

http://estore.bachmanntrains.com/index.php?main_page=product_info&cPath=66_68_170&products_id=1151

Rich

[richg]

Right now I suspect the below is what you have.

http://estore.bachmanntrains.com/index.php?main_page=product_info&cPath=66_68_170&products_id=1151

To date, I do not think Bachmann yet sells a sound decoder like the one in the onboard sound.

Below is a link to the SoundTraxx site and you can see they suggest the TSU-1000 and 28mm speaker.

http://www.soundtraxx.com/choose/step3.php?t=ho&s=Bachmann

Also buy the 9 pin to 8 pin adapter and cut back the shrink a little on the decoder. Remove the 9 pin connector and plug in the adapter cable.
Below is a link about how this is done. The person use to own Litchfield Station, a very good DCC supplier.
There is a LOT of good DCC info there.

Right now, cutting back the shrink for the plug is what you will need if I am correct about your issue.

http://www.mrdccu.com/curriculum/soundtraxx/tsunami.htm

Make sure you get back here as I suspect, others will eventually run into the same issue.

Rich

[d_hitt]

The top picture in reply #6 is exactly what it looks like.  I'll try and get on photo bucket tonight. and upload a picture.  Thanks for your help.

[jonathan]

d_hitt,

If your tender board looks just like the picture in reply #6, as you say:

That small rectangular piece, with the two solder blobs on top, is the dummy plug.  Simply pull that plug and replace it with the decoder.  Should have the same 8 pins as the now exposed receptacle. 

If you install the plug backwards, the locomotive will run, but the lights won't work.  Just turn the decoder plug around if that's the case.  Ask me how I know this. 

Regards,

Jonathan

[richg]

You are not the only one who has been confused by the DC adapter. I belong to a bunch of MRR forums and have seen others who thought it was a PC board. I guess you could say it is a PC board the way it looks, just very small.
I have a couple older Bachmann DCC ready that had two two three pin plugs that did the same as the six pin plug. That confused some in other forums.

Rich

[d_hitt]

Rich and Jonathan,

Just pulled the thing with the two blobs of solder and now everything is abundantly clear!     Not very intuitive of Bachmann.  Thanks for all your help.

[richg]

The ones I bought showed the adapter on the diagram sheet that came with the loco.
To be fair, when you have knowledge of how DCC locos can be set up, the eight pin socket location is quite clear or lack of it in a loco.
Some brands of steamers use only the 9 pin connector, which Athearn calls a Quick Plug.
Some diesels you solder the decoder wires to tabs on the decoder PC board after you remove the two metal jumper clips used for DC operation.
As you gain more DCC experience, you will see there are many, many variables in DCC locos.

Rich