Installing a DCC Decoder in a Diesel Step-by-Step

Installing a DCC non-sound decoder in an O scale diesel "B" unit is about as easy as it gets, this side of 'plug and play.' There are no lights or sound to hook up and there is plenty of room in the wide-body. Click on any photo for a larger view and don't forget to view the videos at the end of the post.

Here we're ready to start, the body's off the chassis of the Weaver diesel and the decoder, a Lenz LE1835W, is at hand.



The LE1835W is an HO decoder, albeit a robust one with a 1.8 amp continuous output.

Here the leads from the left and right rails have been snipped at the motor terminals.



The two feeders from the right rail have been joined with a short length of red wire per the DCC color code for the right rail.



The red wire is connected to the red wire from the decoder and both solder joints have been insulated with heat-shrink tubing. Similarly the left rail leads have been attached to a black wire that has been connected to the black wire from the decoder.



The orange and gray leads have been soldered directly onto the motor terminals (orange to terminal 1, gray to terminal 2) and insulated with heat shrink. This could have been a tighter installation but I deliberately left the wires from the decoder full length in case I ever want to replace this decoder and reuse it elsewhere, I'll have long wires to work with. Therefore all of the excess wire along with the function outputs have been dressed with a cable tie. Finally the decoder has been attached to the weight with double stick tape.



Here's the chassis on the layout ready for a test.



Test run:



Here's the full installation video. Click on the "HD" on the play bar only if you have a fast computer (dual core processor and good video card) and a fast internet connection.