DH165 Board and Multi-Pin Headlights

ModelRailroadForums.com is a free Model Railroad Discussion Forum and photo gallery. We cover all scales and sizes of model railroads. Whether you're a master model railroader or just getting started, you'll find something of interest here.


skyliner

Well-Known Member
At a local show the other weekend, one seller had an Atlas Silver MP15DC labeled "ask about it." I did, and it turned out he had started to convert it to DCC + sound, but stopped midway. I got it for a good price, but now I have to figure out whether I can complete the DCC install myself or not. I've done several installs before, but not of this particular board. Plus, it didn't come with any decoder manuals or instructions.
dcc_board1.jpeg.jpg


The DCC board, from what I can determine, is a Digitrax DH165Q1. I've found the manual online, and figured out which sockets are for what. There's also a Soundbug add-on, on the left above. Connecting power and motor control-- no problem. The issue I've encountered is that the headlight sockets are six-pin and four-pin sockets for the front and rear headlights, respectively. The headlight leads on this locomotive are two-pin plugs.

Does anyone know, is it possible to plug 2-pin lightbulb leads into a 4- or 6-pin socket on this board? i.e. can you use one pair of pins and leave the rest unused? If so, which ones? For example, the picture below is of the headlight lead plugged into just the top two pins of the headlight socket.

I may just scrap this board and get a Soundtraxx one, but I thought I'd give this a shot first. Any suggestions are appreciated.

dcc_board2.jpeg
 

tootnkumin

Well-Known Member
Staff member
Atlas Silver is their DC/DCC ready, line of models and the green circuit board you have there is the motor control and lighting board that was supplied with the model. I have an SD35 of theirs and although the board design is different the 8 pin socket by the light's plug indicates that to be the case. So it's not an actual DCC decoder, that would have to be added. The motor on mine appears to be similar and it also has, as part of the plastic mounting cradle, clips protruding upwards at each end. As does yours also. My board has corresponding slots in it so it presses down over those clips and securely mounts it. Yours does not have those, so that might suggest it doesn't belong to that model at all.
Soundtraxx's and I believe ESU's American Sound decoder boards have those slots as well, it's a universal fitting. So you have choices in the DCC/sound decoder you can use. The Soundbug itself will be surplus, but you may be able to use it's speaker. It may also be that the lights are LEDS, I think Atlas converted over to them some time ago. If that's the case then a resistor for each may be required for the new decoder.
 

skyliner

Well-Known Member
Atlas Silver is their DC/DCC ready, line of models and the green circuit board you have there is the motor control and lighting board that was supplied with the model...

Thanks Toot, but no it is a replacement DCC board. If you look at the first picture, the original DC board is up in the top left corner of the image. The 8-pin socket by the light plug is not the same as a DCC plug-in socket; the pin spacing is slightly different and is intended for Digitrax' Sound Bug add-on, labeled "SFX HERE." It matches the pictures I've found of a DH165 DCC board, but with the sound capacitor already clipped off, since the Sound Bug has one attached.

The board is current-regulated for LEDs, according to the manual I found online. I'm guessing the previous owner picked this board because the electric pickups and motor connection matched the 2-pin plug style, but bailed when they realized the headlight hookups were different.
 

tootnkumin

Well-Known Member
Staff member
Thanks Toot, but no it is a replacement DCC board. If you look at the first picture, the original DC board is up in the top left corner of the image. The 8-pin socket by the light plug is not the same as a DCC plug-in socket; the pin spacing is slightly different and is intended for Digitrax' Sound Bug add-on, labeled "SFX HERE." It matches the pictures I've found of a DH165 DCC board, but with the sound capacitor already clipped off, since the Sound Bug has one attached.

The board is current-regulated for LEDs, according to the manual I found online. I'm guessing the previous owner picked this board because the electric pickups and motor connection matched the 2-pin plug style, but bailed when they realized the headlight hookups were different.
Interesting. Even that other board is different to the one in mine. I learn something new every day. They say that's a sign of getting old. The disadvantage of the Digitrax one is the need to use the plugs they use to fit those sockets and having the tools they use to create the pinouts. Nice for quick board assembly, but not so user friendly for the hobbyist. This what Wikipedia has to say about the MP15DC so if you do decide to use a different board you will know which motor sound to look for
 

Greg@mnrr

Section Hand
I see in your photo a Digitrax sound decoder and speaker. In my experience, Digitax has poor sound for its prime mover. The horn and bells sound effect are okay. I never used a Sound Bug, so I can't comment on its use in locomotives.

I would dump the Digitrax sound decoder, since its not worth the effort for only the bells and horns.

I installed a Digitrax sound decoder, less the speaker, in a locomotive as if it was a typical non-sound decoder.

It maybe a tight fix for a speaker in the MP 15. I just purchased my MILW MP 15's with soiund both Athearn and Atlas models.

Greg
 

skyliner

Well-Known Member
Yeah, on closer inspection I think I will just get a new DCC board, probably a Soundtraxx. There is indeed very little space under the shell, and this Digitrax board (which is primarily for Intermountain locos, I've discovered) has vertical wire sockets. The original DC board has horizontal ones. It's practically impossible to get the shell back on with the wires oriented like that.

I should be able to fit a speaker ok, the black square on the left end of the frame in the first picture is removable, I think it's intended to be the spot for that.
 




Affiliate Disclosure: We may receive a commision from some of the links and ads shown on this website (Learn More Here)


ModelRailroadForums.com is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to amazon.com

RailroadBookstore.com - An online railroad bookstore featuring a curated selection of new and used railroad books. Railroad pictorials, railroad history, steam locomotives, passenger trains, modern railroading. Hundreds of titles available, most at discount prices! We also have a video and children's book section.

ModelRailroadBookstore.com - An online model railroad bookstore featuring a curated selection of new and used books. Layout design, track plans, scenery and structure building, wiring, DCC, Tinplate, Toy Trains, Price Guides and more.

Top