Hi! I have here a Atlas N-scale Dash 8-40B and a DZ125 and I'm thinking about hardwiring this engine instead of dropping in a pcb like a DN163AO which I have not here actually. So my question is: Did anybody the same and can give some advice in doing so. I'm not unexperienced in decoderizing Non-DCC-ready or even models over 40 years old but if someone is out there who can provide me with some trick will be very appreciated. Best regards Mathi
If memory serves me I had the same plan until I removed the shell and found the frame would need a little taken off to get clearance for the decoder. This mechanism doesn't have the old cut out in the rear under the circuit board. I decided to buy the A0 board and save the dremel work. That DZ125 is in a Kato C30-7 now. Martin Myers
All of the photos on the Atlas N scale parts pages show the frame has a refeif under the board over the rear truck. If you have that type of frame the decoder should fit under the board- just hard wire and you are set to go. Got the shell off yet- a photo would show us what you are working with.
I know what you're saying, but at my LHS the price difference between a DZ125 and something like a DN163A0 isn't enough to make me want to mess with the surgery. Still, if you show us the light board we could probably help you figure out how to alter it to solder on a DZ125. I would be concerned about clearance. You may want to test fit first to be sure that it'll all fit.
I have not done this type of project, but I have a few of these boards. Atlas boards like this are kind of tricky because the traces are embedded inside the board so you can't just cut them with a knife. You'll need to, say, drill holes through the board to cut the traces. Probably not that hard actually, but on the other hand, you can't solder directly to the traces for the LEDs and resistors. I'm looking at boards from the earlier runs of these locos, I don't know if they might have changed at some point. Aside from those concerns, it's quite simple to see the traces and determine the layout. I do not see an easy way to keep a common for the LEDs, you'll have to connect them with a wire. I have no idea about fitting the decoder in the rear space under the board, I agree that is the real test here.
Well, after a close examination I decided to do the job. The space under the pcb rear end is at the narrowest 2mm or .08 and the DZ125 is 2,8mm or .11 but it wouldn't be a big deal to file or belt sand the frame down. It is even possible to bend the pcb up and fit the decoder under it. There is some space under shell to do so, but if you are willing to dismantle the entire loco some frame modification is quickly done. BTW there are much smaller DCC or multisystem decoders available here in Europe, DCX or DH for example are just 1,8mm .07 and 1,4mm .06 thick. There are two small holes in the pcb exactly over the two spots where the motor leads touch the board at the underside. Just drill these holes a tad larger, peel of the copper contacts underneath the board, fiddle the orange and grey wire through the holes and solder them to the motor contacts. Red and black wires find their home soldered to the board contacts touching the frame halves. Cut the two traces feeding the LEDs right before the resistor and solder the white and yellow wire to it. Since LEDs do not need as much power as bulbs do to shine bright it is sufficient feeding the light from one frame half cycle but if one likes to cut the other trace off as well and use the blue wire for full power, don't hesitate. All in all is it a very easy job and I say it again: I did it because I have several harnessed decoders at home and fairly paid. They are looking for a nice home and I don't have do waste money for a drop in board, rather buying me a new engine for that money or bring a bin full with caviar for my old lady Thank you guys for you attempt to help! Regards Mathi
