I have always found it useful to have a "simulated locomotive" with an actual motor to test decoders. Back when I started working with DCC, I threw something together from the junk box and ended up using that for many years.
In 2010 that one finally fell apart and I set out to make a nicer one and here it is.
Here's a peek inside. To keep things simple I mounted all of the components on the top half of the two part plastic project box. The size of the box is 5-1/2" x 3" x 1-1/2".
The cord that comes out of the box has a Cinch Jones connector on it that I can plug into these two receptacles on my layout control panel. The layout uses a Digitrax Chief System.
I also have an old Digitrax Big Boy system mounted on a board that I use on the work bench and this decoder tester can also be plugged into that.
Here's a drawing and a parts list along with where I found them.
Besides marking the color for the binding posts, the banana plug sockets are for any special leads needed to connect to board type decoders.
- The nickel plated binding posts are Grayhill 29-100 BLK which I purchase from Allied Electronics. Their part number is 948-7392. At $4.79 each, this was the most expensive part of the project.
- E-Z Hook 9284-5R is a set of banana plug jacks that I found at Fry's Electronics for about $6.00. The Fry's part number is 18206. The full set had 10 jacks with colors matching the wires on a decoder. I did not use the violet or brown ones but if you are working with HO scale decoders that would be something to consider.
- Motor assembly from Kato E8 or PA locomotive. I used this one because the mount was easy to attach to the inside of the box with Walthers Goo. A striped pattern was printed on adhesive labels and attached to the flywheels to the motors rotation would be easy to view through the windows.
- Three yellow LED's taken from Atlas locomotives when they were upgraded to bright white LED's. One each for the white, yellow, and green (F1).