Installation Notebook:
Sound installed in a Stewart U25B Diesel
This great looking and running loco can sound good, too.


The Atlas style light board is replaced with the Soundtraxx decoder. Styrene sheet is used to assure that the speaker is tight against the left (fireman’s) side of the loco where the open grill vents the sound. The back pressure comes out the opposite side grill.
Replacing the white LEDs with bulbs eliminates the LC flicker from this decoder. There is enough metal to pull the heat of this bulb away from the shell and avoid warping.
If you wish to keep the white LEDs (or upgrade to Golden White LEDs) add the extra parts to remove the glow. For wiring details check the diagram below:
