Using an LM-3S with the Accessory program loaded I've set up a Bachmann Spectrum Long Caboose (large scale) for dead rail control of the included lighting and to add some sound effects. This model has a highly detailed interior and electronics for an HO decoder for simple on/off control of the lighting. I wanted individual control and needed room for the LM, batteries, and speaker, so the stock electronics were removed including surgically removing the AA battery box interior to make room for a speaker. I'm still waiting for a small LiIon battery and speaker to arrive, but I have it fully functional using a larger LiIon pack and a too large speaker just hanging around in the interior for now. A full write-up with more photos is posted at
www.largescalecentral.com but here are a few highlight pictures and video of operation.
For the marker lamps I included a few non-prototypical functions just for fun - Flashing or alternating markers!
The stock board just before removal...
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Wiring schematic...
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Wired (less battery & speaker) and ready for operation...
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Operational test...
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Video of project program Version 1...
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And video of using the Firebox lighting effect to simulate kerosene lanterns...
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Not sure how to post video, so I'm just including links for now.
Mod edit: Embedded video links.